@conference{nokey,

title = {New 1,2-benzothiazine derivatives as inhibitors of cyclooxygenase with membrane perturbing potency},

author = {Jadwiga Maniewska and Katarzyna Gębczak and Łucja Cwynar-Zając and Berenika Szczęśniak-Sięga},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

publisher = {Polish Biophysical Society and Adam Mickiewicz University},

address = {ul. Uniwersytetu Poznanskiego 2, 61-614 Poznan},

abstract = {Cyclooxygenase (COX) is an enzyme located in the lumen of the endoplasmic reticulum, the Golgi apparatus and the nuclear membrane of the cell, embedded with hydrophobic fragments in the lipid bilayer of the membrane. COX catalyzes the process of prostanoid synthesis, i.e. prostaglandins, prostacyclin and thromboxane from arachidonic acid [1]. However, since inflammation has been linked to cancer development, the search for new, safer anti-inflammatory drugs has become even more important [2,3].

In our previous studies, we obtained a series of 1,2-benzothiazine derivatives with anti-inflammatory and analgesic activity confirmed in in vivo tests on mice [4].

In this study, a series of 1,2-benzothiazine derivatives (Tab. 1) were evaluated. In particular we investigated the interactions of the potential drugs with lipid bilayers, an important consideration for membrane permeability and overall pharmacokinetics. We have used differential scanning calorimetry method (DSC) to determine the interactions of studied compounds with phospholipid bilayers as models of biological membranes [5]. All examined compounds decreased the main transition temperature of phospholipid used to obtain the model membranes (DMPC) in a concentration-dependent manner. The addition of 1,2-benzothiazine derivatives to phospholipid also resulted in broadening of the transition peaks. Moreover, all examined compounds decreased the enthalpy of the DMPC main phase transition. It was therefore concluded that all the compounds interacted with phosphatidylcholine model membrane affecting its thermotropic properties. Although the greatest impact on the main transition temperature change was observed for the compounds PR25, PR49 and PR50. In addition, we evaluated the ability of studied compounds to inhibit COX-1 and COX-2 activity and selectivity using cyclooxygenase inhibition assay. ....



Our findings suggest that the 1,2-benzothiazine derivatives could serve as potential lead candidates for the development of safer anti-inflammatory agents},

type = {Poster},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Toxicity assessment of chitosan-based films modified with quercetin and metals - preliminary wound healing studies},

author = {Beata Bielska and Abdelkrim El Kadib and Katarzyna Miłowska},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

publisher = {Polish Biophysical Society and Adam Mickiewicz University},

address = {ul. Uniwersytetu Poznanskiego 2, 61-614 Poznan},

abstract = {Chitosan has found applications in various industries such as medicine, agriculture, textiles, food and environmental protection due to its many beneficial properties. In medicine, chitosan-based materials are used as dressings to speed up the healing process of injuries and burns. In skin and bone tissue engineering, chitosan is used to produce a variety of materials including membranes, hydrogels, sponges and fibres. Scientific literature also indicates the potential of chitosan and chitosan-engineered materials as drug carriers, including anti-cancer drugs, intranasal drugs, gene delivery drugs, prenatal drugs and ocular drug delivery systems [1-3].

Quercetin is a flavonoid with potent antioxidant and anti-inflammatory properties. As an antioxidant, it protects cells from oxidative stress, which promotes tissue regeneration. In addition, quercetin has anti-inflammatory effects by inhibiting the activity of enzymes and reducing the secretion of pro-inflammatory cytokines, which further promotes the healing process, especially during the inflammatory phase [4-5].

Based on their individual properties, we concluded that the combination of quercetin and chitosan films may induce synergistic effects, combining the properties of both substances for more effective wound healing. As a prelude to wound healing, we are evaluating the effects of these films on erythrocytes, peripheral blood mononuclear cells (PBMC) and human dermal fibroblasts (BJ line) in vitro.

The aim of this study is to evaluate the biocompatibility of chitosan films modified with quercetin and metals (Ag, Au, Cu, Bi) with blood cells and skin fibroblasts (BJ line) by assessing haemotoxicity, cytotoxicity and genotoxicity.

Chitosan films showed low toxicity to human erythrocytes, around 5%. Silver-containing nanomaterials showed higher toxicity (above 10%), depending on the silver content of the particle. In cytotoxicity analyses, silver-containing nanocomposites were more toxic than other chitosan films. Other variants showed a favourable toxicity profile, suggesting further research into their potential use in wound healing. Analysis of damage to genetic material showed low levels of damage. The addition of quercetin, a natural antioxidant, may partially mitigate the adverse effects of silver. Therefore, chitosan-quercetin metal films may have reduced cytotoxicity to skin fibroblasts and other human cells, increasing their potential for use in tissue engineering and wound healing. ...},

type = {Poster},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Physicochemical Descriptors of Halogenated Flavonoids: Insights into Their Antibacterial Potential},

author = {Martyna Perz and Kamila Środa-Pomianek and Anna Pałko-Łabuz and Daria Szymanowska and Edyta Kostrzewa-Susłow and Olga Wesołowska},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

publisher = {Polish Biophysical Society and Adam Mickiewicz University},

address = {ul. Uniwersytetu Poznanskiego 2, 61-614 Poznan},

abstract = {Flavonoids are natural compounds found in plants, known for their anti-inflammatory, cytotoxic, and bactericidal properties. The analysis of flavonoid descriptors is essential for developing new derivatives, predicting biological properties, and understanding their mechanisms of action. With the rise in antibiotic-resistant bacteria, exploring flavonoid derivatives containing halogen atoms (bromine, chlorine), has become increasingly important. These substituents can significantly enhance the antibacterial properties of flavonoids, making them promising candidates for future therapeutic applications [1,2]. In silico studies, leveraging computational methods, offer a powerful approach to elucidate the structure-activity relationships of flavonoids, predict their interactions with biological targets, and explore their pharmacokinetic properties [3].

This study focused on three halogenated flavonoid compounds: 3'-bromo-5'-chloro-2'-hydroxychalcone, 8-bromo-6-chloroflavanone, and 8-bromo-6-chloroflavone. Laboratory experiments and SwissADME in silico analyses were conducted to examine their physicochemical properties, including melting point, molecular weight, polarity, log P, and others. Although the compounds have similar molar masses, differences in structure, bond flexibility, and insaturation were found to influence their biological activity [4]. 

The results showed that 8-bromo-6-chloroflavanone effectively inhibited the growth of pathogenic bacteria without significantly impacting probiotic bacteria, while 3'-bromo-5'-chloro-2'-hydroxychalcone, and 8-bromo-6-chloroflavone suppressed both probiotic and pathogenic bacteria. The presence of bromine and chlorine atoms enhanced the bactericidal effects compared to quercetin, a commonly studied natural compound [4].

These findings highlight the potential of halogenated flavonoids as alternatives to current natural products, particularly in regulating intestinal microbiota. Further research will explore their mechanisms of action and include additional in vitro and in vivo studies, focusing on their effects on HCT 116, FHC, and Caco-2 cell lines. ....},

type = {Poster},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Activity of immucillins on the purine nucleoside phosphorylase (PNP) from H. pylori and on the bacterial growth},

author = {Marta I. Wojtyś and Marta Narczyk and Monika Krystian and Ivana Leščić Ašler and Agnieszka Bzowska},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

publisher = {Polish Biophysical Society and Adam Mickiewicz University},

address = {ul. Uniwersytetu Poznanskiego 2, 61-614 Poznan},

abstract = {Helicobacter pylori is a gram-negative, microaerophilic bacterium which colonizes the gastric and duodenal mucosa of half of the world's human population, and its presence may cause serious diseases, such as stomach and duodenal ulcers and stomach cancer. Unfortunately, the available therapies fail in 20% of patients due to increasing resistance to the antibiotics used. Therefore, it is very important to search for new molecular targets to design new drugs enabling eradication of H. pylori [1].

Immucillins are a group of synthetic compounds that are analogues of purine nucleosides. They inhibit PNP-catalyzed reactions by imitating their transition state [2]. Kicska et al. [3] have shown that immucillin H (Imm-H) is an inhibitor of PNP from P. falciparum (causing malaria in humans), which, like H. pylori, does not synthesize purines and purine nucleosides de novo, suggesting that it may also inhibit the H. pylori PNP enzyme and the replication of this bacterium. Therefore we decided to characterize interactions of Imm-H and other immucillins with PNP from H. pylori 26695 strain, and their influence on the replication of H. pylori.

Immucillins, which form a strong but slowly forming complex with PNP [2], were incubated with the enzyme in a reaction mixture lacking substrate, and then the reaction was initiated by adding the missing substrate (m7Guo). We showed that immucillin A (Imm-A) (Ki = 1.3 ± 0.2 nM) is a potent inhibitor of H. pylori 26695 PNP, similar to Imm-H (Ki = 9.8 ± 0.8 nM). In contrast, MT-DADMe-ImmA does not inhibit H. pylori PNP.

We determined minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) values for immucillins against the reference strain H. pylori 26695 using the double serial dilution method in liquid medium [4]. Imm-A inhibits the growth of H. pylori (MIC = 80 μM (21 μg/ml)) in contrast to Imm-H, which does not affect the growth of this pathogen. However, Imm-A has no bactericidal effect on H. pylori, while the MBC value for MT-DADMe-ImmA is 5 μM (1.47 μg/ml), but its target is a different H. pylori enzyme.

Our studies show that among the compounds from the immucillin group, the most promising for use in the eradication of H. pylori in humans is Imm-A, which, as an adenosine analogue, does not interact significantly with the host PNP. ...},

type = {Poster},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {The role of the mitochondrial BK_{Ca} channel in the physiology and damage of respiratory epithelial cells induced by urban particulate matter},

author = {Adrianna Dabrowska-Hulka and Karolina Pytlak and Kamila Maliszewska-Olejniczak and Jakub Hoser and Mirosław Zajac and Bogusz Kulawiak and Piotr Bednarczyk},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

publisher = {Polish Biophysical Society and Adam Mickiewicz University},

address = {ul. Uniwersytetu Poznanskiego 2, 61-614 Poznan},

abstract = {Recently, it has been shown that the inner mitochondrial membrane's potassium channels (mitoK) are involved in cytoprotection. Therefore, protecting epithelial cells from particulate matter (PM)-induced damage may be related to activating potassium channels in the mitochondria.

To verify the role of mitochondrial large-conductance Ca2+-regulated potassium (mitoBKCa) channel in cytoprotection in response to stress induced by PM, we performed a series of experiments using patch-clamp, transepithelial electrical resistance assessment mitochondrial respiration measurements, fluorescence methods for the ROS level and mitochondrial membrane potential assessment, and cell viability measurements using trypan blue staining. In the human bronchiolar lung epithelial cell damage model (16HBE14o- wt), particulate matter 4 m in diameter was used (PM4.0).

We observed that PM decreased the transepithelial electrical resistance in HBE cells dose-dependently. The effect was partially abolished by quercetin, mitoBKCa channel activator. Penitrem A (BKCa channel inhibitor) reversed the effect of quercetin. The patch-clamp findings confirmed that the effect is associated with channels. Quercetin activated the mitoBKCa channel, abolishing the effect of penitrem A. The results were compatible with mitochondrial membrane and respiration measurements. Quercetin decreased the mitochondrial membrane potential and increased mitochondrial respiration. The effect was abolished by penitrem A only in whole-cell respiration measurements. PM-induced ROS levels are reduced at the cellular and mitochondrial levels. It correlates with cell viability results for quercetin, which increases HBE cell viability after PM administration. The toxic effect was also shown at the mitochondrial level. The PM incubation with the cells substantially reduced the mitochondrial function, which was measured as respiration control with fully uncoupled mitochondria compared to the inhibited electron transport chain.

To support our data, we used an analog of quercetin-isorhamnetin, a substance that has one hydroxyl group changed to a methoxy group. After its application, Isorhamnetin has no effect on the mitoBKCa channel activity, respiratory rate, and mitochondrial membrane potential. Additionally, we used CRISPR/Cas9 technology in 16HBE14o- cells to generate cell lines lacking the alpha subunit of the BKCa channel encoded by the KCNMA1 gene. Mitochondrial patch-clamp experiments showed the absence of an active mitoBKCa channel in knockout cells (HBE BK).

A better understanding of the relationship between mitochondrial metabolism and cell pathophysiology could aid in the search for effective cytoprotection strategies. Perhaps, by using naturally derived mitochondrial BKCa channel activators, we will learn to support and induce these mechanisms to counteract the consequences of PM-induced damage. ...},

type = {Poster},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Radiogenic effects on ion channel function: investigating the role of BK_{Ca} potassium channel in DNA damage response},

author = {Michał Fryc and Patrycja Chuchała and Aleksandra Lenartowicz-Gasik and Martyna Araszkiewicz and Mateusz Jakielaszek and Patrycja Kamińska and Urszula Kaźmierczak and Agnieszka Korgul and Jacek Rzadkiewicz and Wojciech Soroka and Bogusz Kulawiak and Piotr Bednarczyk and Kamila Maliszewska-Olejniczak},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

publisher = {Polish Biophysical Society and Adam Mickiewicz University},

address = {ul. Uniwersytetu Poznanskiego 2, 61-614 Poznan},

abstract = {Glioblastoma multiforme (GBM) is the most common and aggressive primary brain tumor arising from astrocytes and is classified as WHO grade 4 astrocytoma. Standard treatment includes surgical resection, chemotherapy with temozolomide, and radiation therapy, but the low survival rate of patients highlights the urgency for innovative and more effective therapeutic tools [1]. The response of this type of tumor to chemoradiotherapy is poor, possibly due to a higher repair activity of the genetic material, among other causes. DNA double-strand breaks (DSBs) are an essential type of lesion to the genetic material, which have the potential to trigger processes of cell death or cause gene aberrations that promote tumorigenesis. Radiotherapy eliminates tumor cells by causing DSBs. Therefore, targeting the cellular DNA damage response is a promising strategy to enhance tumor radiosensitivity.

Ionizing radiation (IR) has been shown to stimulate ion transport, which is crucial for the DNA damage response (DDR) [2]. The DNA damage response is a highly coordinated cellular defense mechanism that sustains genomic integrity by detecting and repairing DNA lesions. The pivotal role of DDR in cellular function and survival is emphasized by the association of DDR defects with many human disorders, including cancer, aging, and neurodegenerative diseases. Although the DDR mechanisms have been extensively studied, most research has focused on cytosolic or nuclear proteins rather than biological membrane-present ion channels. Recently, potassium channels have been described as 'oncochannels' involved in tumor progression and treatment resistance in many cancers, highly expressed in bone, breast, ovary, and prostate cancer and glioma [3]. Due to the high drug sensitivity of these channels, targeting them may represent a new approach to treating glioma. According to the latest reports, oncochannels contribute to glioblastoma stem cell properties, program and execute cell migration and invasion, regulate the cell cycle, and confer therapy resistance. Cell migration and invasion in glioblastoma are critically dependent on changes in the level of Ca2+. Moreover, overexpression of large-conductance Ca2+-regulated potassium channel (BKCa) in glioblastoma can promote tumor progression and therapy resistance, which also presents an opportunity for developing novel therapeutic strategies. BKCa channels play a significant role in regulating mitochondrial function and redox homeostasis. These channels are modulated by ROS and other redox-active molecules, which influence their function and, consequently, the redox state of the cell [4]. Modulating BKCa potassium channels could alter cancer cells' response to radiotherapy and potentially overcome treatment resistance. Therefore, the primary goal is to investigate the mechanism of the BKCa channel in DNA damage response in modulation, enhancing the radiosensitivity of cancer cells and overcoming treatment resistance using ionizing radiation and pharmacological approaches. ...},

type = {Poster},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {The role of ion transport induced by modified ionophores and compounds of natural origins},

author = {Jakub Hoser and Mirosław Zajac and Anna Sekrecka-Belniak and Marta Jedrzejczyk and Adam Huczynski and Piotr Bednarczyk},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Cystic fibrosis is the most common genetic disease among rare diseases. It is caused by mutations in the cftr (cystic fibrosis transmembrane conductance regulator) gene, which encodes the CFTR anion channel. The CFTR channel defect results in abnormal transport of ions and water across the epithelium, leading to thick and sticky lingering mucus in the affected organs [1]. The activity of the CFTR channel is dependent on ATP molecules. Therefore, increasing cellular ATP levels can promote chloride secretion and contribute to better epithelial hydration.

Increasing cellular ATP levels can be induced using mitochondria-directed ionophores capable of transporting ions across biological membranes. Their activity can lead to depolarization of the inner mitochondrial membrane and increase of cellular respiration. In addition, ionophores can affect the electrophysiology of epithelial tissues by participation in various signaling pathways. The same effect can be achieved by compounds of natural origin available in a varied diet. Examples of such compounds are flavonoids, which are capable to activate ion channels and modulating metabolic pathways [2].

The ability of the ionophores used in the study to transport ions across biological membranes and the effects on the electrophysiology of cellular monolayers were studied in Ussing chamber and by Black Lipid Membrane technique. The effects of the tested compounds on changes in the cellular respiration level were studied in Oroboros system. Transepithelial chloride transport was determined in an Ussing chamber. ATP levels were determined by the commercially available bioluminescent assay. In addition, migration assays, viability assays, ROS level and transepithelial electrical resistance of the monolayers were performed. The assays were conducted on respiratory cell lines such as the cancer cell line A549 and the bronchial epithelial cell line 16HBE14o-.

The results of the experiments showed that the targeted compounds exhibited the ability to transport ions across biological membranes, and in a concentration-dependent manner to increase cellular respiration. Ussing chamber experiments showed that the tested mitochondria-directed ionophores did not affect the chloride current flowing through cell monolayers. On the other hand, the experimentally selected flavonoid- luteolin appeared to increase intracellular ATP concentration, transepithelial electrical resistance, affect metabolism, proliferation and modulate chloride secretion.

These findings suggest that luteolin may strengthen the barrier function of human bronchial epithelial (HBE) cells and holds potential to support epithelial hydration mechanisms—offering a promising perspective for therapeutic strategies in cystic fibrosis. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {The role of the potassium and chloride transport in the development of inflammation induced by particulate matter},

author = {Sandra Jaworowska and Kamila Maliszewska-Olejniczak and Agnieszka Łukasiak and Jakub Hoser and Mirosław Zając and Piotr Bednarczyk},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Particulate matter (PM) poses an increasing threat to human health. Their effects on the human body include the development of inflammation [1]. PM has been shown to exhibit immunomodulatory properties in bronchial epithelial cells by inducing the production of cytokines such as tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) [2].

To investigate the role of ion channels in the development of inflammation, bronchial epithelial cell lines were used: wild-type (HBE WT), with a deletion in the gene encoding the α subunit of the large-conductance potassium channel (HBE ΔαBKCa), and with a mutation of the gene encoding the CFTR channel (CFBE). Each cell line was exposed to various concentrations of PM and assessed for changes in reactive oxygen species production, proinflammatory cytokine secretion (IL-6, TNF-α), mitochondrial respiration (via oxygen consumption rate), intracellular calcium levels, and transepithelial electrical resistance (TEER).

PM exposure significantly increased ROS synthesis and amplified IL-6 and TNF-α release, particularly in HBE ΔαBKCa and CFBE cells. TNF-α induced the highest inflammatory response in HBE ΔαBKCa and CFBE cells compared to HBE WT cells, as measured by IL-6 quantification, suggesting a role for ion channels in the inflammatory response. Mitochondrial function was also adversely affected, as evidenced by reduced maximal respiratory capacity in both HBE ΔαBKCa and CFBE cells relative to HBE WT. Additionally, depending on its concentration, PM increased intracellular calcium ion levels in all cell lines. Finally, PM exposure led to a pronounced reduction in TEER, with CFBE monolayers displaying the most significant susceptibility to barrier disruption.

These studies highlight the vulnerability of potassium and chloride transport disorders in airway epithelial cells to PM-induced injury, which encompasses oxidative and inflammatory stress, mitochondrial dysfunction, and compromised epithelial barrier integrity. Targeting BKCa channel modulation and mitigating oxidative/inflammatory pathways could represent promising therapeutic strategies to protect airway health against environmental pollutants. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Polystyrene nanoparticles interfere with DNA repair mechanisms in human intestinal Caco-2 cell line model},

author = {Agata Kustra and Karolina Pytlak and Bogusz Kulawiak and Piotr Bednarczyk and Kamila Maliszewska-Olejniczak},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Nanoplastic (NP) occurs ubiquitously in aquatic and terrestrial environments, and its harmful biological effects have been observed in a variety of organisms, i.e. bacteria, plants, and animals [1]. Studies on human cells provide fundamental information on key mechanisms of toxicity that will provide answers to the question of whether and how NP poses a health risk. Mechanisms of toxicity mainly include membrane disruption, and production of reactive oxygen species, and may induce DNA damage including oxidative DNA damage (single-strand breaks, SSBs) and DNA double-strand breaks (DSBs) [2]. The emerging concern over environmental nanoparticles, particularly polystyrene (PS) nanoparticles, involves that there is some evidence suggesting that PS particles may be genotoxic in mammalian cells, however, the molecular basis is unclear [3].

This study investigates the interactions between NPs and an immortalized cell line of human colorectal adenocarcinoma cells (Caco-2) by exposing them to various NPs concentrations 50, 100, 400, 800, and 1200 μg/mL). The Caco-2 human epithelial cell line is a prevalent model for studying the intestinal epithelial barrier [4]. Derived from colon cancer, a noteworthy feature of this cell line is its spontaneous differentiation into a monolayer that closely resembles absorptive enterocytes functionally and morphologically, reflecting those found in the intestine.

We assessed potential cytotoxicity using the clonogenic assay and examined NP genotoxicity using the alkaline comet assay and flow cytometry assays (PARP1-dependent apoptosis and cell cycle changes). Our findings indicate a moderate level of NP cytotoxicity observed in the clonogenic assay. Moreover, our preliminary results showed no changes in cell cycle distribution and a minimal increase in the level of apoptotic cells. In addition, no single or double DNA strand breaks were observed. Since we did not observe direct effects, we expect indirect effects mediated by other molecules (e.g., induction of reactive oxygen species (ROS), inhibition of DNA repair mechanisms). To test the likely production of reactive oxygen species by Caco-2 cells in the presence of PNP, DCFDA fluorescent probe staining was performed to determine the level of ROS. After exposure to polystyrene nanoparticles, induction of oxidative stress was observed. We also performed RNA isolation and cDNA synthesis for qPCR assay, which allowed us to check the expression of characteristic genes involved in DNA repair pathways. In particular, critical genes involved in the base excision repair (BER) and DSB repair pathways were downregulated, suggesting a potential impairment of the cell's ability to repair oxidative DNA damage.

This study highlights the sublethal effects of nanoplastics on intestinal barrier cells. It underscores the possible risks of chronic exposure to these environmental contaminants, which can lead to genome instability and other long-term health consequences.},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Electrophysiological Assessment of BK Channel Activity in LRRC26-Positive Cells},

author = {Sz. Talarek and A. Adamska and Maciej Gawlak and Beata Dworakowska and Ewa Nurowska},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {The auxiliary γ1 subunit of the BK channel, LRRC26, is known to dramatically shift the activation voltage of BK channels by approximately 140 mV toward hyperpolarization, enabling channel opening at resting membrane potentials and in the absence of Ca²⁺ [1,2]. While LRRC26 expression has been previously reported in epithelial cells, vascular smooth muscle cells, and certain cancer lines, it has not been observed in neuronal cells.

We investigated, using immunofluorescence and the patch-clamp technique, the expression and functional impact of LRRC26 in various cell types, including breast cancer cells (T47D), prostate cancer cells (LNCaP), rat cerebellar Purkinje neurons, and HEK293 cells co-transfected with BK and γ1 cDNAs. Immunofluorescence confirmed LRRC26 presence across all cell types, including Purkinje neurons, where its expression had not been previously reported.

Single-channel patch-clamp recordings under symmetric K⁺ and 1 EGTA conditions revealed functional BK-γ1 complexes only in LNCaP cells and HEK293 cells expressing both BK and γ1. T47D cells exhibited only rare BK activity, with no evidence of γ1-mediated modulation, even after BK channel transfection. Similarly, Purkinje neurons displayed BK activity only under depolarizing or Ca²⁺ presence conditions, with no signatures of γ1-associated hyperpolarized activation. To examine whether the formation of BK-γ1 complexes could be influenced by metabolic conditions, we investigated the effects of glucose availability in Purkinje cells. However, under glucose-limited conditions, no enhancement in BK-γ1-type activity was observed.

Our findings suggest that while LRRC26 protein is detectable in multiple cell types, its functional coupling with BK channels may be cell-type specific and condition-dependent. This implies that LRRC26 may serve additional, possibly non-membrane-associated, cellular roles beyond its established function as a BK channel auxiliary subunit. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {The inhibitory effect of resveratrol on Kv1.3 channels in jurkat T cells – a putative role in anti-cancer activity},

author = {Andrzej Teisseyre and Anna Uryga and Kamila Środa-Pomianek and Anna Palko-Łabuz},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Resveratrol (3,4’,5 – trihydroxystilbene) is a biologically-active plant-derived polyphenol, which exerts anti-viral, anti-bacterial, anti-fungal, antiinflammatory, anti-atherosclerotic, anti-cancer and neuroprotective effects. It is also a modulator of activity of various types of potassium channels. Our previous studies have shown that resveratrol is also an inhibitor of voltage-gated potassium channels Kv1.3 in human T lymphocytes [1]. Voltage-gated potassium channels Kv1.3 encoded by the KCNA3 gene are widely present among different tissues [2]. The channels may be expressed not only in the plasma membrane, but also in the inner mitochondrial membrane (mito Kv1.3 channels) [3]. The channels’ activity plays a significant role in a regulation of proliferation and apoptosis of Kv1.3 channelexpressing cells [3]. The channels’ expression may be significantly changed in some cancer disorders [3]. Inhibitors of the channels may putatively find clinical application in therapy of various diseases, including some cancer disorders characterized by an over expression of Kv1.3 channels, such as melanoma, pancreatic ductal adenocarcinoma (PDAC), multiple

myeloma and B-type chronic lymphocytic leukaemia (B-CLL) [3]. It is known that some lipophilic small-molecule organic inhibitors of Kv1.3 channels may exert antiproliferative and pro-apoptotic activity on Kv1.3 channel-expressing cancer cells, selectively eliminating them while sparing the normal ones [3]. To the group of lipophilic small-molecule organic inhibitors of Kv1.3 channels in cancer cells belong also some compounds from the groups of flavonoids, chalcones and statins [3]. The inhibitory effect on the channels may significantly be augmented upon a coapplication of flavonoids and chalcones with the statins: simvastatin and mevastatin [3]. The augmented inhibitory effect on the channels may be co-related to an improved pro-apoptotic activity of these compounds, applied in a combination, on Kv1.3 channel-expressing cancer cells [3]. ....},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Assessment of TRPM2 Expression in Lymphocytes T Under Hypoxic Conditions},

author = {Artur Wardaszka and Anna Smolarska and Piotr Bednarczyk and Joanna K. Bujak},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {The immune system plays a crucial role in maintaining homeostasis, with T lymphocytes orchestrating adaptive immune responses through cytokine production and cytotoxic activity [1]. Effective T cell activation is essential for combating infections and malignancies. However, in pathophysiological environments such as the tumor microenvironment (TME), factors like hypoxia and oxidative stress can impair T cell function, reducing their immunological efficacy [2, 3].

The TRPM2 (Transient Receptor Potential Melastatin 2) ion channel is a redox-sensitive, non-selective cation channel activated by ADP-ribose, reactive oxygen species (ROS), TNF-α, and Concanavalin A. It has been implicated in immune regulation by modulating T cell activation, proliferation, and calcium signaling, particularly under oxidative stress. Nevertheless, its role under hypoxic conditions remains incompletely understood.

This study aimed to assess TRPM2 gene expression in peripheral blood lymphocytes (PBLs) cultured under hypoxia (1% O₂) and chemically induced hypoxia (CoCl₂), following CD3/CD28-mediated activation. Gene expression of TRPM2, along with activation markers CD25 and CD69, was analyzed using quantitative RT-PCR.

Our results demonstrate increased TRPM2 expression in activated lymphocytes under both hypoxic conditions, suggesting its involvement in adaptive responses to low-oxygen stress. Activation markers confirmed T cell stimulation; however, their expression was attenuated in hypoxia, particularly under chemical hypoxia, indicating impaired full activation. These findings suggest that TRPM2 may play a role in T cell adaptation to hypoxic stress and could represent a potential target in modulating immune responses within hostile microenvironments. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Effect of mutations in the KCNMA1 gene on BK channel activity},

author = {Anna Sekrecka-Belniak and Beata Dworakowska and Piotr Koprowski and Piotr Bednarczyk},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Large-conductance calcium-activated K+ channel (BK) gating involves three major molecular processes: voltage sensor movement, sensor-pore coupling, and pore opening. Recently, a mechanism for BK channel gating was proposed, suggesting that the structure of the pore does not undergo significant physical movement but, like many other ion channels, undergoes relatively small structural changes accompanied by hydrophobic gating. The deep-pore region of the human BK channel (residues G310-P320) undergoes hydrophobic dewetting transitions in the calcium-free state, which prevents the permeation of water and small ions. The barrier to K+ permeation arises from the vapor gap that separates the selectivity filter from the bulk solution [1].

The cytoplasmic entry to the BK pore expands to a large central cavity that turns into the selectivity filter. The walls of the central cavity are primarily hydrophobic. Mutations in this region change the open probability of the BK channel, increasing or decreasing it depending on the polarity and hydrophobicity of substituted amino acids [2]. The same region is involved in channel blocking by paxilline [3].

The study aimed to investigate the effect of the point mutation in the KCNMA1 gene, encoding the pore-forming alpha subunit, on BK channel function. We examined three substitute mutations, which decrease the hydrophobicity of amino acids lining the pore's central cavity: L312A, F315D, and A316G. The HEK293 cells were transfected with plasmids encoding either the wild-type (WT) or one of the mutated alpha subunits. All mutants formed functional ion channels. The properties of the channels were analyzed in cell-attached and inside-out configurations using the patch clamp technique. Compared to the WT, all three mutants exhibited increased channel activity (Fig.1). Studied mutations affected channel unitary amplitude, kinetics, and sensitivity to Ca2+, indicating that alterations in hydrophobicity within the central cavity modulate the energy landscape of the gating process. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Oligomer formation by the immune response protein IFIT1: a biochemical and biophysical study},

author = {Anna Stankiewicz-Drogon and Joanna Grzymkowska and Tomasz Kobiela and Joanna Krasowska and Beata Wielgus-Kutrowska and Renata Grzela},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {There are many ways for a eucaryotic organism to defend against pathogenes. One of these is the ability to recognise foreign genetic information, hinder its expression, and target it for degradation. Proteins from the IFIT family play a significant role in this process. Eucaryotic mRNA is equipped with a special cap structure at the 5’ end, consisting of m7Gppp and additional methylations at the first and second nucleotides of the mRNA chain. RNA without these modifications is recognised and bound by the IFIT1 protein, preventing the association with the eucaryotic translation initiation factor eIF4E and, consequently, arresting the translation of foreign proteins [1].

Recently, many efforts have been devoted to introducing specific modifications to the cap structure to increase its affinity towards eIF4E and decrease its affinity towards IFIT1 [2, 3]. This was predominantly done for medical purposes, to obtain an even stronger affinity for modified mRNA than for mRNA with native caps and to promote the translation of particular proteins that could serve as vaccines, including anty-tumour ones.

In order to study the affinity of IFIT1 for differentially modified caps, as well as the dynamics of these interactions, it was necessary to use IFIT1 in monomeric form so that the protein-cap interactions could be examined at a 1:1 ratio. The aim of the presented study was to obtain monomeric IFIT1 protein by introducing mutations to the C-terminal domain responsible for the homodimerisation process, and further to investigate and compare the biochemical and biophysical properties of the wild-type and mutated proteins [4]. For the preliminary characterization, the wild-type and mutated IFIT1 proteins were subjected to observation by differential light scattering (DLS) and differential scanning fluorimetry (DSF). All of the proteins studied produced advanced oligomeric forms, which nevertheless differed in both structure and stability. The most stable forms were obtained for the native IFIT1 protein, and the least stable for the double mutant protein. Moreover, the native IFIT1 protein was found to be the most prone to forming high-order oligomers. The stability of the aggregates formed during incubation of proteins at 37°C was tested using proteinase K digestion and further observation of the degradation products. Again, the most stable were the aggregates formed by the native IFIT1 protein, while the aggregates formed by both mutants were much more susceptible to proteolytic degradation.

During the studies, it was not possible to obtain monomeric particles, which suggests that the introduced mutations did not sufficiently inhibit the homodimerisation process. Nevertheless, the mutagenesis compromised the structural integrity of IFIT1, affecting its ability to maintain stable oligomeric assemblies under physiological conditions. Studying the oligomerisation of the IFIT1 protein and the role of the structures formed during this process opens up a new, previously unknown area in the broader immune response. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Molecular spectroscopy as a power tool for studying the porphyrin–DNA interaction},

author = {Olga A. Ryazanova},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {The porphyrins are macrocyclic compounds with unique spectroscopic and photophysical properties. They are widely used as photosensitizers in anticancer photodynamic therapy, probes for the structure and dynamics of nucleic acids, anti-viral and antimicrobial agents, and carriers of antisense oligonucleotides for their delivery, stabilizers of G-quadruplexes of telomeric DNA etc. The interest in studying porphyrin-DNA interaction is caused by the great potential of the data obtained for biomedical application, nanotechnology, and molecular electronics.

In this work we discuss the application of various spectroscopic techniques (absorption spectroscopy, polarized fluorescence, absorption and fluorescence melting, fluorimetric titration, and resonance light scattering) to study the binding of two cationic meso-porphyrins (Fig. 1) and its conjugates with phenazine dye to nucleic acids of different primary and secondary structure, including single-stranded [1–3], double-stranded [4–6], and quadruplex [4, 6–8] ones.

....

Using the spectroscopic methods, the binding modes of

the porphyrins to nucleic acids were identified, the

thermodynamic parameters of binding were obtained,

the formation of porphyrin aggregates on the surface of

the biopolymer was revealed, and their size was

determined.

....},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Bound protein influences triplet state relaxation time of AF488 fluorescent probe},

author = {A. Smuczyńska and Igor Kumela and Barbara P. Klepka and Michał K. Białobrzewski and Radost Waszkiewicz and Anna Niedźwiecka},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Fluorescent dyes are commonly used to study the properties and interactions of biomolecules. While the spectral parameters of the Alexa Fluor series are well known, the triplet state lifetimes are usually assumed to be in the range of microseconds without further specification.

Here we investigate the triplet state dynamics of a bright and photostable dye, AF488 (an isomerically pure 5-analogue of Alexa Fluor 488), when conjugated to acid-rich intrinsically disordered and standard globular proteins using fluorescence correlation spectroscopy (FCS). By varying the laser excitation power and the viscosity of the environment, we accurately characterize the changes in the triplet state relaxation time. While AF488 typically exhibits a stable triplet lifetime over a range of environments, we observe a significant shortening of the triplet state lifetime when the dye is bound to highly acidic IDPs},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Quartz Crystal Microbalance with Immobilised Mitochondria as a Label-Free Biosensor for Rapid Screening of Neuroprotective Drugs},

author = {Julia Anchimowicz and Sławomir Jakieła},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Disturbed mitochondrial morphology and dynamics are now recognised as key factors in neurodegenerative disorders such as Parkinson's and Alzheimer's diseases1,2. Therefore, quantifying these alterations quickly and without fluorescent labels is essential for the discovery of truly disease-modifying therapies. Herein, we present a label-free biosensor utilizing a quartz crystal microbalance (QCM) for real-time monitoring of morphological changes in isolated mitochondria from SH-SY5Y neuroblastoma cells. The mitochondria are immobilized onto a cysteaminefunctionalized, 10 MHz quartz crystal housed within

a polycarbonate microfluidic chip. This chip is securely sealed with O-rings and four thumb screws, allowing the piezoelectric crystal to be easily replaced within two minutes, facilitating rapid serial measurements without risk of cross-contamination.

Our results demonstrate that exposure of differentiated SH-SY5Y cells to the Parkinson's toxin MPP⁺ (100 μM) resulted in a 138 ± 25 Hz reduction in frequency, reflecting mitochondrial matrix contraction and fragmentation, which is consistent with observations in live-cell studies3. Subsequent perfusion with the dynamin-related protein 1 inhibitor Mdivi-1 (10 μM) increased the frequency by 312 ± 24 Hz, indicating the effective restoration of mitochondrial integrity, which supports the previously documented anti-fragmentation effects4. Control experiments using empty crystals exhibited a drift of less than 1 Hz, confirming that the observed frequency variations specifically reflect changes in mitochondrial morphology.

The presented QCM-microfluidic platform offers a powerful, high-throughput route to identifying mitochondria-targeted neuroprotective agents and tracking therapeutic efficacy in neurodegenerative disease research by coupling nano-sensitive gravimetric sensing with a rapidly disassembled microfluidic chip ....},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Study of the expression of cancer biomarkers - EphA2 and survivin using automated capillary electrophoresis},

author = {Hubert Grel and Magdalena Stobiecka},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Poland has one of the highest rates of lung cancer incidence and mortality in Europe. Currently, the mortality rate is around 40 per 100,000 people. One of the main problems of oncology is late diagnosis and the difficult monitoring of changes in the disease during treatment. This is due to the type of therapy undertaken and the way in which cancer cells respond to the treatment. Monitoring of the biomarkers can then be significantly difficult due to differences in gene expression [1]. Therefore, in order to design a sensitive exosome-based biosensor to monitor the patient's condition from liquid biopsy, it is necessary to examine the expression of proteins in response to treatment, as protein levels in exosomes are derivative of expression levels in their origin cells.

In this study, we utilized a drug used in lung cancer therapy - paclitaxel (PTX)[2]. First, we determined the concentration of PTX necessary to induce changes in healthy alveolar cell line CI-huArlo and the non-small cell lung cancer A549 cell line. For this purpose, we conducted an AlamarBlue viability test. The selected concentration correlated with that obtained in blood flow during chemotherapy. Early and late apoptosis as well as necrosis assays were performed with flow cytometry technique using Annexin V and Draq7 labeling. To check the apoptotic activity of the cells, PARP1 protein expression was investigated, and then the expression of survivin and EphA2 proteins was measured in both cell types, before and after paclitaxel treatment, respectively. It was shown that there is a significant difference in survivin expression between non-treated CI-huArlo and A549 cells. The significant difference in EphA2 expression between treated and non-treated healthy as well as cancer cells was also presented. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Advancing biomedical research through microfluidics: Microfluidic systems for single-cell analysis, high-precision oxygen release imaging, mechanobiology studies, and dynamic cell culture.},

author = {Barbara Kupikowska-Stobba and Sławomir Błoński and Tetuko Kurniawan and Piotr M. Korczyk},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Microfluidic systems offer precise control over fluid flow and microscale environments, making them powerful tools for high-throughput analysis, manipulation, and imaging of cells or droplets. A central aim of our research is to develop microfluidic platforms tailored to the specific needs of biological and medical research. One of our most advanced technologies, currently in commercial prototype development, is a microfluidic system for single-cell oxygen saturation and release imaging. Developed in close collaboration with the University of Oxford, it enables a detailed assessment of red blood cell function [1, 2]. The system was successfully applied to study human kidneys perfused with stored blood during transplantation, where organ respiration was monitored under cold perfusion [3]. The findings revealed a strong correlation between kidney oxygen consumption and erythrocyte oxygen-release

capacity – challenging the conventional notion that oxygen delivery is determined solely by blood flow and oxygen content.

In parallel, we developed microfluidic devices capable of generating mechanical gradients in epithelial tissues through controlled deformation. In partnership with the University Grenoble Alpes, we investigated how curvature influences calcium signaling and gene expression in epithelial monolayers, providing new insights into tissue morphogenesis and mechanotransduction [4].

We also developed systems for single-cell immobilization and manipulation, enabling long-term observation of isolated cells or spheroids in individual

droplet incubators or microscale cell traps, with several hundred replicates achievable in a single experiment.

These cell traps were used to study the formation of immunosuppressive niches in Hodgkin lymphoma by analyzing interactions between CAR-T lymphocytes and cancerous B-cells at single-cell resolution. Finally, we present a static droplet microfluidic incubator designed for dynamic, long-term culture of bacterial and mammalian cells with real-time, singlecell monitoring. Utilizing a controlled coalescence mechanism, the device supports versatile, automated nutrient delivery and waste removal protocols, which can be tailored to the specific requirements of different cell types. In vitro studies confirmed its effectiveness in sustaining long-term cultures of E. coli and A549 epithelial cells under optimized shear stress conditions. The results showed improved cell growth, as well as controllable cell organization—supporting the formation of either confluent monolayers or 3D spheroid-like structures. The device’s modular design allows seamless integration with upstream and downstream microfluidic components, as well as closed-loop feedback control systems.

Together, these advances highlight the potential of microfluidics to investigate complex biological phenomena with high precision and throughput, supporting diverse applications in cell biology, transfusion medicine, organ preservation, immunology, and drug discovery.},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Biosensors as Diagnostic Tools for early detection of cancer biomarkers},

author = {Katarzyna Ratajczak and Magdalena Stobiecka},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Cancer diseases are one of the leading causes of death worldwide. Tumors arise as a result of uncontrolled proliferation and abnormal cell growth, which can lead to the invasion of surrounding tissues and metastasize. Early diagnosis is the most important strategy against cancer, in which molecular biomarkers playing an increasingly important role. Cancer biomarkers are molecules present in the patient's body whose levels correlate with the presence, stage, or progression of the cancer disease [1-2].

Among the biomarkers, survivin and EphA2 can be distinguished, which have significant diagnostic and prognostic value. Survivin, encoded by the BIRC5 gene, has a dual function: it inhibits programmed cell apoptosis and regulates cell division. Moreover, EphA2 is a tyrosine kinase receptor from the ephrin family involved in cell adhesion, migration, and invasion processes. It should be noted that overexpression of these biomarkers has been demonstrated in several tumors including breast, lung, colorectal and prostate cancers. High levels are associated with aggressive disease progression, resistance to chemotherapy and radiotherapy, and poor prognosis. In healthy tissues, their expression is minimal. Both biomarkers are currently investigated as targets for novel anticancer therapies [3-4].

In recent years, a great interest in the use of biosensors has been made for the detection of cancer biomarkers. Biosensors are analytical devices that integrate biological elements (such as enzymes, antibodies, nucleic acids) with physical, chemical or optical transducers, enabling the detection of the presence of a specific analyte. Among the numerous classes of biosensors, optical and electrochemical biosensors have gained particular importance due to their sensitivity, selectivity and potential for miniaturization and point-of-care applications [5]. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Electrochemical DNA biosensors for the detection of survivin cancer biomarker},

author = {Diana Więcławik and Magdalena Stobiecka},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Due to the rising numbers of new cancer cases around the world and specific features of this disease, such as the high mortality rates, fast tumor growth, invasion into neighboring cells and cancer cells’ migration, the early diagnosis and prompt effective cancer treatment strategies become crucial in the fight against cancer [1-2].

Survivin (Sur) is the smallest member of the inhibitor of apoptosis proteins (IAP) family. It became a diagnostic and prognostic cancer biomarker and potential therapeutic target owing to its strong expression in malignant tumors and very weak expression in normal differentiated cells [3].

The goal of this work was to design and test electrochemical DNA biosensors for the detection of mRNA survivin in cancer cells and exosomes as well as for the investigation of human colorectal cancer cells metastasis with different metastatic potential.

The biosensor was based on redox-labelled molecular beacons immobilized on the gold electrodes via thiol groups. In the presence of complementary oligonucleotides, the analytical signal from electrochemical marker decreased due to the higher rigidity of DNA duplex and longer distance to the electrode surface.

The consecutive steps of the gold electrodes modification were characterized using a cyclic voltammetry technique. The efficiency of developed biosensors in real samples, containing lysate from cancer cells was also investigated. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Proximity labeling reveals new interactors of mitochondrial BK_{Ca} channels},

author = {Bogusz Kulawiak and Monika Żochowska and Shur Gałecka},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Mitochondria play a vital role in cell function, particularly in ATP production through oxidative phosphorylation, enabled by the membrane potential across the inner mitochondrial membrane. Potassium channels identified in this membrane regulate mitochondrial activity by influencing membrane potential, respiration rate, and ROS production. Their activity has also been linked to cytoprotection. One of the best-characterized channels is the mitochondrial large-conductance calcium-activated potassium (mitoBKCa) channel, similar in structure and function to plasma membrane BKCa channels.

In this study, we aimed to identify protein interactions of BKCa/mitoBKCa channel subunits, including mitochondrial partners. We used the TurboID technique, which labels nearby proteins via biotinylation, generating a construct with the β4 subunit of the BKCa channel fused to TurboID ligase. Additional constructs targeted TurboID to specific cellular compartments to control for nonspecific labeling. Experiments were performed in HEK293T and U-87 MG astrocytoma cells.

Mass spectrometry of biotinylated proteins from mitochondrial fractions and whole-cell lysates showed that the β4 subunit labeled proteins from the ER, cytosol, plasma membrane, nucleus, and mitochondria. Among mitochondrial proteins, we identified MICOS complex components and proteins involved in complex IV assembly. However, co-immunoprecipitation did not confirm direct interactions with these mitochondrial proteins.

The confirmed interactor was TMX1, a protein mainly localized to the ER, especially in mitochondrial-associated membranes (MAMs). TMX1 interacted with both β4 and α subunits of the BKCa channel. As an oxidoreductase, TMX1 may modulate BKCa function through redox regulation. Previous research also showed that TMX1 regulates calcium transfer between the ER and mitochondria, affecting cellular metabolism. This suggests that TMX1–BKCa interaction may also influence this process. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {What is the role of mitoBK_{Ca} channel in bronchial epithelium exposed to particulate matters (PMs)?},

author = {Karolina Pytlak and Kamila Maliszewska-Olejniczak and Mirosław Zając and Piotr Bednarczyk and Bogusz Kulawiak},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Bronchial epithelial cells, which line the lower respiratory tract, form a monolayer that serves as a natural barrier between the external environment and the internal milieu of the body. These cells are continually exposed to harmful agents such as pathogens, allergens, and air pollutants, all of which can contribute to respiratory diseases and increased mortality. Potassium channels play a key role in lung physiology, including ion homeostasis, mucus secretion, and maintenance of epithelial integrity. Among them, mitochondrial potassium (mitoK) channels facilitate potassium ion influx into mitochondria, leading to reduced mitochondrial membrane potential, enhanced respiratory chain activity, and increased mitochondrial respiration, ultimately influencing reactive oxygen species (ROS) production. Activation of these channels also modulates mitochondrial matrix volume and prevents calcium ion overload within mitochondria. Our previous research identified the presence of mitochondrial large-conductance Ca²⁺-activated potassium channels

(mitoBKCa) in human bronchial epithelial (HBE) cells. In this project, we investigated the role of mitoBKCa in mitochondrial physiology under exposure to particulate matters (PMs). Using CRISPR/Cas9 genome editing, we established a novel 16HBE14o⁻ cell line with a disruption of the KCNMA1 gene (HBE Δα), which encodes the pore-forming α subunit of the BKCa channel. In HBE Δα cells, neither the α subunits nor channel activity was detectable. Notably, these cells exhibited impaired mitochondrial function, characterized by reduced cellular respiration and altered OXPHOS-dependent ATP production. Additionally, we observed a reorganization of the respiratory chain in the absence of the BKCa channel. To further elucidate the molecular mechanisms underlying these effects, we performed RNA sequencing to analyze transcriptomic profiles of both wild-type and HBE Δα cells following short- and long-term exposure to low and high concentrations of PMs. The absence of the BKCa channel resulted in significant transcriptional alterations in genes associated with mitochondrial function. Moreover, PMs exposure induced pronounced changes in the transcriptome, with a distinct response observed between the two cell lines. These findings underscore the critical role of BKCa channels in maintaining mitochondrial function and cellular homeostasis in bronchial epithelial cells, particularly under conditions of environmental stress such as PM exposure. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Functional reconstitution of diacylglycerol kinase epsilon and its complex with ROMK2 potassium channel in native copolymer nanodiscs},

author = {Milena Szafraniec and Gabriela Traczyk and Natalia Roszkowska and Katarzyna Kwiatkowska and Piotr Koprowski},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Diacylglycerol kinase epsilon (DGKε) catalyzes phosphorylation of 1-stearoyl-2-arachidonoyl (18:0/20:4) diacylglycerol (SAG) thus converting it into 1-stearoyl-2-arachidonoyl phosphatidic acid (SAPA). Our previous studies using the Turbo-ID method have demonstrated that DGKε is a member of the ROMK2 potassium channel proxisome. Moreover, direct interaction of these two proteins has been confirmed by co-immunoprecipitation. Additionally, phosphatidic acid, being DGKε product, has been shown to stimulate the activity of ROMK2 in artificial lipid bilayers [1].

In the present work, we demonstrate that both ROMK2 and DGKε can be efficiently solubilized from mammalian cells using nanodisc-forming copolymers of various structures. Additionally, as revealed by fluorescent assay followed by TLC separation, the activity of DGKε is retained in many nanodiscs. Of the copolymers examined, the low-charged zwitterionic Sulfo-Cubipol proved to be the most effective in solubilization of both proteins, as well as in maintaining the activity of DGKε. Moreover, this copolymer enabled to assess the impact of ROMK2-DGKε interaction on the kinase activity. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Liquid–Liquid Phase Separation of a Highly Charged Coral Protein Regulates Calcium Carbonate Formation},

author = {Barbara P. Klepka and Agnieszka Michaś and Tomasz Wojciechowski and Anna Niedzwiecka},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Non-classical crystallization theory challenges traditional models by proposing that crystal formation proceeds through intermediate states such as amorphous calcium carbonate (ACC) or polymer-induced liquid precursors (PILPs) [1]. Although ACC has been identified in the coral Stylophora pistillata [2], direct evidence for PILPs remains limited, with most insights inferred from the analysis of solid phases. In the context of biomineralization in living organisms such as corals, the polymers that are thought to be involved in skeleton formation are coral acid-rich proteins (CARPs) [3], which are secreted at the coral tissue–skeleton interface. These proteins have been shown to bind calcium and influence crystal morphology [3] and polymorph selection [4].

In this study, we demonstrate that the aspartic- and glutamic acid-rich protein (AGARP), an intrinsically disordered protein with an exceptionally high charge of -148 e per molecule and the first cloned CARP from the model coral species, Acropora millepora, modulates calcium carbonate formation via liquid-liquid phase separation (LLPS) [5].

Using fluorescence correlation spectroscopy, we observed that AGARP and Ca²⁺ ions form early aggregates in non-crowded, water-like solutions prior to the emergence of ACC, as confirmed by scanning electron microscopy with energy-dispersive X-ray spectroscopy.

On the other hand, under molecular crowding conditions that mimic the endoplasmic reticulum and extracellular matrix environments, where AGARP is processed after biosynthesis and exported, respectively, AGARP forms liquid protein–calcium condensates (LPCCs) through LLPS, as revealed by confocal laser scanning fluorescence microscopy and fluorescence recovery after photobleaching experiments. When exposed to carbonate ions, these LPCCs serve as crystallization precursors, and the resulting CaCO3 phases exhibit smooth edges that differ markedly from the sharp edges formed in the absence of AGARP.

Our findings suggest that the LPCCs could be biologically relevant precursors in calcium carbonate biomineralization and highlight the importance of LLPS and macromolecular crowding in this process. This study provides a new perspective on the processes involved in the skeleton formation and offers valuable insights for designing bioinspired materials. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Distinguishing specific and nonspecific cation interactions with acid-rich proteins using FCS},

author = {Igor Kumela and A. Smuczyńska and Barbara P. Klepka and Michał K. Białobrzewski and Radost Waszkiewicz and Anna Niedźwiecka},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Biomineralisation in corals is modulated by the secretion of proteins into the extracellular skeletal organic matrix. A subclass of these proteins, the coral acid-rich proteins (CARPs), are thought to regulate calcium carbonate formation by binding to calcium ions. However, the exact nature of this interaction remains unclear. In particular, the selection of the calcium carbonate polymorph depends on the ionic composition of the environment, since the presence of Mg2+ cations is necessary to obtain the naturally occurring aragonite. We investigate the conformational behaviour of two highly acidic intrinsically disordered proteins (IDPs) upon interaction with counterions, Ca2+ and Na+, by measuring the changes in their hydrodynamic size with increasing salt concentrations using fluorescence correlation spectroscopy (FCS). By varying both the ionic strength and the identity of the cation, we measure the influence of ionic conditions on protein dimensions. Our results show a strong dependence of the hydrodynamic size on the cation type and concentration. While the changes observed for the monovalent cation are consistent with the predictions of Debye screening, the results obtained for the divalent cation differ significantly, suggesting counterion-specific interactions beyond simple electrostatics. We are able to separate the overall screening from putative site-specific cation binding and show that only a subset of the observed behaviour can be fully explained by classical Debye-Hückel theory.},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Condensation of Galectin-3 N-terminal domain in Martini 3 Coarse-Grained Simulations},

author = {Paweł Rogowski and Bartosz Różycki},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Galectin-3 is a protein comprising two distinct domains: a N-terminal domain (NTD) of approximately 120 amino acid residues and a carbohydrate-recognition domain (CRD) that binds specific carbohydrates. The NTD is characterised by a high content of proline, glycine, and tyrosine residues, contributing to its flexibility and lack of a well-defined structure. It plays a crucial role in the ability of galectin-3 to self-associate and form transient multimers, which is essential for many of its biological functions, including cell adhesion, signaling, and immune regulation. The NTD has also been linked to various pathological conditions, including cancer, inflammation, and fibrosis. Recent experimental studies have shown that both the full-length galectin-3 and its NTD can form biomolecular condensates in a process of liquid-liquid phase separation (LLPS).

To investigate LLPS of the NTD with near-atomic resolution, we employed molecular dynamics simulations using the Martini 3 coarse-grained force field [1]. We systematically fine-tuned the solute-solvent interactions within the Martini 3 force field to achieve an optimal agreement with the experimental phase diagram of the NTD, ensuring the accuracy and relevance of our simulations. Our simulations revealed a concentration-dependent condensation of the NTD, and we observed significant differences in the geometric properties of the NTD chains between the condensed and dilute phases. Specifically, parameters such as the radius of gyration, the maximum interatomic distance, and the end-to-end distance were found, on average, to be higher for the NTDs in the condensates than for the dilute NTDs in an ionic solution, which indicates that the NTD chains adopt more extended conformations within the condensates. Furthermore, the auto-correlation time of the end-to-end distance was higher in the condensates than in the dilute phase, suggesting slower conformational dynamics of the NTD within these structures. As a matter of fact, the diffusion coefficient of the NTD in the condensates was found to be approximately two times lower than in the dilute phase. In addition, analysis of intra-molecular contacts revealed that tyrosine and tryptophan residues interact with the rest of the NTD chain about two times more frequently than other residues, suggesting their key role in driving the NTD condensation. Furthermore, analysis of inter-molecular contacts demonstrated that these interactions, on average, are an order of magnitude stronger in the condensates than in the dilute phase. The condensed NTDs were found to exhibit reduced amounts of contacts with both ions and water molecules, with an average of 1.45 ± 0.02 ions and 39.8 ± 0.6 water molecules within its contact distance. This is in marked contrast to dilute NTDs, which displayed significantly higher contact numbers (6.2 ± 0.6 ions and 163 ± 10 water molecules, respectively). This observation suggests that the NTD condensation is accompanied by a decrease in the NTD solvent accessibility and by a preference for protein-protein interactions over protein-solvent interactions. Taken together, our results provide detailed insights into the molecular mechanisms underlying the NTD condensation, highlighting the crucial role of interactions involving tyrosine and tryptophan residues, reduced solvent accessibility, and altered conformational dynamics within the condensates. These findings could provide a foundation for future research aimed at modulating the NTD condensation for therapeutic purposes, impacting our understanding and treatment of galectin-3 related diseases. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {The intrinsically disordered AB region: a key modulator of the molecular properties of human RXRγ},

author = {Katarzyna Sołtys and Krzysztof Skowronek and Dominika Bystranowska and Krzysztof Wycisk and Andrzej Ożyhar},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {The human retinoid X receptor γ (hRXRγ) is a ligand-dependent transcription regulator that belongs to the nuclear receptor superfamily. It is characterized by conserved structural domains and a unique, intrinsically disordered N-terminal AB region. While the AB region is known to modulate the transcriptional activation of target genes, its structural role within the full-length receptor remains poorly understood. Here, we show that the AB region shapes the structural organization of hRXRγ. Comparative analyses of the full-length receptor (hRXRγ) and a deletion mutant lacking the AB region (ΔABhRXRγ) reveal that the AB region modulates oligomerization, stability, and conformational heterogeneity. Rather than acting independently, the AB region integrates with the receptor core, fine-tuning its structural variability and enhancing its responsiveness to environmental conditions. These findings position the AB region as a key modulator of hRXRγ's structural plasticity and, potentially, its transcriptional activity.},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Investigation of aggregation properties of yeast DCs1 protein},

author = {J. Kokosza and Marek Warzecha and Maciej Łukaszewicz},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Decapping Scavenger (DcpS) enzyme was initially identified as one of the factors playing role in mRNA turnover. DcpS proteins have been found in eukaryotes of varying complexity, including yeast, nematodes, and humans. DcpS belongs to the superfamily of HIT (Histidine Triad) proteins that utilize the evolutionary conserved motif (His-X-His-X-His-X, where X denotes hydrophobic amino acids) to cleave the 5’,5’- triphosphate bridge within a mRNA 5’cap structure, releasing m7GMP and ppN or diphosphate terminated oligoribonucleotide [1].

In addition to its role in mRNA cap metabolism, human DcpS has been reported to function in the pre-mRNA splicing and the regulation of miRNA turnover [2, 3], as a potential therapeutic target in specific cancer types [4], and in the development of nervous system [5]. Interestingly, several mutations in DcpS have been linked to neurological disorders, e.g. ARS syndrome [6].

Recently we have shown that human DcpS protein undergoes aggregation into a beta-sheet-like amyloid fibrils in vitro under physiological temperature, what may be connected to its function in neurological disfunctions development. Moreover, the nematode DcpS (Cenorhabditis elegans DcpS) has also been shown to form amyloid-like fibrils under the same experimental conditions [7].

Here, we investigated the aggregation properties of DCS1 protein – a DcpS homologue from the unicellular eukaryote (Saccaromyces cerevisiae). DCS1 share 32,55% or 31,42% identity of amino acid sequence with human DcpS and C.elegans DcpS, respectively, and overlap in the structural alignment with hDcpS and CeDcpS. Bioinformatic analysis of potential aggregation-prone regions with WALTZ and Cordax prediction models revealed the presence of two such motifs in the DCS1 amino acid sequence, similarly to human and nematode homologs. However, initial screening of the aggregation process using a Thioflavin T (ThT) assay, in which an increase in ThT dye fluorescence is observed upon binding to the stacked beta-sheets present in amyloid fibrils, showed no such effect for DCS1. Also, the DCS1 solution remained transparent over the assay period, in contrast to the CeDcpS solution under the same experimental conditions. In summary, the preliminary results obtained here for DCS1 suggest a lack of, or much weaker, aggregation propensity for this DcpS homologue from a lower unicellular eukaryote, which requires further investigation. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Is the development of molecular biophysics methods subject to the laws of evolution?},

author = {Bogdan Lesyng},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {The development and selection of methods, models, and theories in time from the point of view of their usefulness in scientific research resembles the process of biological evolution with its Darwinian selection mechanisms. The question is, how does the evolutionary tree of useful and functional experimental and theoretical methods of molecular biophysics look? Below, I present a hierarchical tree applied to AI/ML molecular biophysics problems. The analysis and the trees were created using the Anthropic Claude application [1]. For a general overview, see e.g. [2]. During the presentation, I will present the full tree, which accounts for the evolution of experimental and theoretical biophysics methods. Also, among other things, a flowchart tree will be presented. In addition to their cognitive value, such trees can be very useful in teaching biophysics methods, because they provide a global view of the current state of knowledge and research methodologies.

AI/ML MOLECULAR BIOPHYSICS APPLICATIONS

├── Traditional ML (2000s-2015)

│ ├── Support Vector Machines (2000s)

│ ├── Random Forests (2005s)

│ ├── Principal Component Analysis (2000s)

│ └── Hidden Markov Models (2000s)

├── Deep Learning (2010s-present)

│ ├── Convolutional Neural Networks (2010s)

│ │ ├── Image Classification (2012)

│ │ ├── Cryo-EM Analysis (2015)

│ │ └── Medical Imaging (2017)

│ ├── Recurrent Neural Networks (2010s)

│ │ ├── Sequence Analysis (2015)

│ │ └── Time Series Prediction (2018)

│ ├── Transformer Models (2017-present)

│ │ ├── Protein Language Models (2019)

│ │ ├── ESM Models (2021)

│ │ └── ProtTrans (2021)

│ └── Graph Neural Networks (2018-present)

│ ├── Molecular Property Prediction(2018)

│ ├── Protein Function Prediction (2020)

│ └── Drug-Target Interaction (2021)

├── Structure Prediction (2018-present)

│ ├── AlphaFold (2018)

│ │ ├── AlphaFold 1 (2018)

│ │ └── AlphaFold 2 (2020)

│ ├── ColabFold (2021)

│ ├── ChimeraX AlphaFold (2021)

│ └── ESMFold (2022)

├── Dynamics Prediction (2019-present)

│ ├── Boltzmann Generators (2019)

│ ├── Neural ODEs (2020)

│ ├── Graph-based Dynamics (2021)

│ └── Diffusion Models (2023)

└── Drug Discovery (2015-present)

├── Virtual Screening (2015)

├── Generative Models (2018)

├── Molecular Optimization (2020)

└── Target Identification (2022)

...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Predicting structure and properties of polytryptophan crystals},

author = {Łukasz Mioduszewski},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Polymers containing aromatic sidechains can exhibit interesting charge transport properties. Theoretical investigations suggest they may even become high-temperature superconductors under specific conditions [1]. Aligning polymer chains in a periodic lattice (or even chaotic, quasi-periodic structure [2]) may help in forming a stable transport network. For this reason I studied polytryptophan chains (containing 12 or less monomers). As very hydrophobic molecules, they are hard to crystallize under typical conditions (it was never done, so the possibility of achieving a periodic structure is only hypothetical). Their crystallization is itself a challenge, but possible crystal structures are worth considering (due to interesting properties they may exhibit).

Polymer Structure Predictor (PSP) [3] was used to construct infinitely long polymer chains, and then align them in parallel in a crystal lattice. The method included inserting new chain in different configurations with the respect to the existing one, then repeating the process until a stable crystal structure was found (see Figure 1). This is a great simplification, but aligning 12-monomer molecules consisting of hundreds of atoms proved to be too complex for crystal structure prediction algorithms.

This simplified model of a polytryptophan crystal allowed for DFT calculations [4]: the Fermi energy and band structure were calculated. Surprisingly, no band gap was found, which suggests such a crystal would be a conductor (but no sign of superconductivity was found). ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {In silico design of molecularly imprinted polymers for remdesivir and its active metabolite},

author = {Agnieszka Powała and Renata Rybakiewicz Sekita and Teresa Żołek},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Remdesivir is a broad-spectrum antiviral drug that gained significant attention during the COVID-19 pandemic due to its activity against RNA viruses,including SARS-CoV-2. After administration, remdesivir is metabolized in the body into its pharmacologically active analogs, such as GS-441524 (Fig.1), which inhibit viral RNA polymerase, thereby disrupting viral replication. Monitoring the concentrations of remdesivir and its metabolites in patients’ body fluids is crucial for assessing therapeutic efficacy and ensuring safe, individualized dosing. [1] Despite the existence of methods for determining remdesivir, few have been adequately validated, highlighting the need to develop new, reliable methods for quantifying these compounds. ...

Molecularly imprinted polymers (MIPs) are a promising tool for the selective extraction of remdesivir and its metabolites from biological fluids. MIPs are synthetic materials with binding sites specifically designed for target molecules. Their selectivity, stability, and reusability make them ideal for detecting and extracting small molecules from biological samples. In

personalized medicine, MIPs can be used to monitor therapeutic drug levels, enabling accurate and costeffective detection of pharmaceuticals and their metabolites. [2]

This study focused on applying computational chemistry tools to the synthesis of molecularly imprinted polymers (MIPs) for antiviral drug recognition. Molecular modeling techniques can significantly accelerate MIP development by enabling rational design prior to experimental synthesis. Quantum chemical calculations (DFT) and molecular mechanics were employed to investigate the interactions within pre-polymerization complexes of remdesivir, its active metabolite GS-441524, and a set of selected functional monomers. The primary objective was to identify the most suitable monomers exhibiting the strongest interactions with these compounds in the pre-polymerization complex and to determine the optimal monomer-to-template molar ratio for designing and synthesizing MIPs capable of selectively recognizing remdesivir and its metabolite in patients’ blood samples. The theoretical analysis of the MIP binding site considered carbazole-based monomers and a solvent mixture of acetonitrile:DMSO (8:2, v/v).

The results revealed significant differences in the binding affinities of the selected monomers, identifying promising candidates for MIP design. 

....

Based on the calculations of Gibbs free energy values, a molar ratio of 1:4 (template:functional monomer) was identified as optimal for forming stable pre-polymerization complexes involving remdesivir, its metabolite, and selected functional monomers (Fig. 2). These findings provide a theoretical foundation for developing molecularly imprinted polymers for remdesivir and its metabolite, GS-441524, for antiviral drug detection, with potential applications in personalized medicine...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Inside the project agritech: different approaches for the evaluation of safety parameters along the agri-food supply chain},

author = {Alessia Calabrese and Alessandro Capo and Michelangelo Pascale and Sabato D'Auria and Maria Staiano},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {The National Center for the Development of New Technologies in Agriculture (Agritech)[1] is an initiative in Italy funded by the Italian Ministry of University and Research under the National Recovery and Resilience Plan (PNRR). One of the primary objectives of this project is to promote the advancement of agri-food production, with a strong focus on safety, traceability, and security throughout the supply chain. This approach aligns with the core principles of the European Green Deal, which aims to create fair, healthy, and environmentally friendly food systems[2].

One of the significant challenges in managing the food supply chain is the risk of microbiological and chemical contamination. Food inspections are conducted at production sites and processing plants to meet regulatory requirements. These inspections typically involve random sampling and laboratory analysis, which can take two or more days to provide results. The time and cost involved in each analysis often lead to reduced oversight, increasing health risks. Furthermore, due to these time and cost constraints, analyses cannot be performed at every stage of the supply chain, allowing products to reach grocery stores before thorough checks are made. This scenario underscores the urgent need to enhance food safety, and the limitations of current analysis methods motivate us to propose new approaches for detecting contaminants along the food supply chain. 

In this project, we are working on three different methodologies to detect specific contaminants that may be present in the cereal, dairy, and wine value chains. Our targets are aflatoxin B1 (AFB1), aflatoxin M1 (AFM1), and ovalbumin (OVA). AFB1 is one of the most widespread and hazardous mycotoxins that can contaminate various foods, including cereals, before and after harvest. AFM1 is a by-product of the hepatic metabolism of AFB1 and is frequently found in the milk of animal species fed with AFB1-contaminated fodder [3]. Lastly, OVA, one of the oldest fining agents used in winemaking, is also an allergen. Traces of OVA [4] that potentially remain in wine after filtration can trigger allergic reactions in sensitive consumers.

To detect these contaminants, we are working on three distinct methodologies: Surface Plasmon Resonance, Fluorescence Immunoassay, and Electrochemical Impedance Spectroscopy. The common principle behind these methods is to monitor the binding interaction of specific antibodies with the selected targets.

A more detailed overview of these three approaches will be presented, subdividing them according to the respective food chain and the analyte target. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Multistep loss of catalytic Activity and ligand binding ability of hexameric Purine Nucleoside Phosphorylase from E. coli},

author = {Marta Narczyk and Agnieszka Bzowska},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {It is commonly accepted paradigm that enzymes exist in two states, active or inactive and that enzyme catalysis is such a complicated process, that a change in any biophysical property of an enzyme leads to a total loss of catalytic ability. What's more, the catalytically disabled protein is often considered as unable to bind ligands. Here however, we present purine nucleoside phosphorylase (PNP), which breaks this paradigm.

PNPs are key proteins in the purine salvage pathway, that enables cells to recover purine bases and pentose-1-phosphate from used nucleosides. PNPs are widely studied for their potential medical applications, e.g. as targets in antitumour therapies, while inhibitors of human PNP are considered immunosuppressive agents [1]. Lack of de novo nucleosides synthesis pathway in some bacteria makes PNP a target for potential drugs in designing therapies against such organisms [2].

But PNPs are also remarkable molecular machines, especially hexameric PNP from E. coli, which in the course of our studies, turned out to be, itself, an interesting research object. E. coli PNP in the apo form is a homohexamer, both in terms of sequence and three dimensional structure of monomers. However when it comes to symmetry it is trimer of dimers (Fig. 1, top). Upon binding of phosphate, one of the substrates, in some subunits conformational change occurs: segmentation of H8 helix and movement of its N-terminal part towards the active site, partially closing the entrance. According to the flip-flop model, catalysis occurs in the closed active sites, while substrates bind also to the adjacent open active site [3].

We have discovered that this enzyme does not inactivate in one step, but rather goes through several intermediate states, with various distribution of the closed active sites, which is reflected in various catalytic and phosphate binding abilities of such intermediates. Following the activity decay over time and measuring a dependence of dissociation constants for phosphate on the activity of the enzyme sample, we have shown that a gradual loss of the catalytic activity towards natural substrates correlates with the reduced ability to bind phosphate. Taking into account these data and known crystallographic structures of E. coli PNP, we were able to identify specific intermediates on the pathway from the fully active to the inactive enzyme (Fig. 1, bottom). ....},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Illuminating cancer: bioimaging potency of 3-(1,1-dicyanoethenyl)-1-phenyl-4,5-dihydro-1H-pyrazole (DCNP)},

author = {Anna Palko-Łabuz and Kamila Łupińska and Dorota Zając and Martyna Perza and Olga Wesołowska and Kamila Środa-Pomianek and Lech Sznitko},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Optical imaging serves as a valuable method for observing and comprehending biological processes in both in vitro and in vivo systems. It provides a powerful means of visualizing key chemical and biological activities in living cells in real-time. Thus, it offers several advantages for disease diagnosis, including high spatial resolution, quick data acquisition, no ionizing radiation risks, affordability and/or minimal invasiveness. Optical imaging relies on the use of luminogens, which have the ability to absorb light and convert it into detectable fluorescence. To achieve high-quality fluorescence bioimaging, it is essential to use organic exogenous contrast agents that offer biocompatibility, brightness, and photostability. Unfortunately, commonly used organic dyes exhibit non-emissive properties during aggregation, making them less suitable for medical applications. Aggregation-induced emission (AIE) molecules have been identified as ideal candidates for fluorescence bioimaging, mostly because the hydrophilic feature of the bio-environment can cause almost instant aggregation for typically hydrophobic organic dyes. Thus, AIE luminogens offer benefits such as brighter emission from the aggregates than in the dilute solution, and the potential to exhibit large Stokes shifts and high resistance to photobleaching.

3-(1,1-dicyanoethenyl)-1-phenyl-4,5-dihydro-1H-pyrazole, known as DCNP, comprises organic “push–pull” molecule with nonlinear optical characteristic [1]. In our studies, DCNP was obtained through a three-step synthesis. The first step involved double N-alkylation of phenylhydrazine derivatives, carried out in an aqueous medium under microwave irradiation to accelerate the reaction [2]. The second step consisted of Vilsmeier–Haack formylation, while the final step was a Knoevenagel condensation, leading to the formation of the target molecule. In the next step, AIE behaviors of the compound were evaluated. Increased fluorescence intensity of DCNP was observed in solutions where the ratio between solvent and nonsolvent were changing. In vitro experiments were undertaken to investigate the bioimaging potency of DCNP, focusing on the cancer illumination. We used sulforhodamine assay (SRB) to assess the influence of the compound on the viability of selected cancer cell lines derived from different origin. Our results showed low cytotoxicity of DCNP suggesting its high potential for use with living cells. The staining potency of selected AIE compound was examined by fluorescence microscopy and spectrofluorimetric method. We found the strong enhancement of fluorescence intensity of DCNP in the presence of model lipid bilayers what suggested high visualization capacity of the compound. Time- and concentration-dependent accumulation of the probe was investigated and its ability to localize into the cells was examined. Due to the important role of fluorescent dyes in monitoring cell death, the biodistribution of DCNP in cells undergoing apoptosis was also examined. Further studies will be conducted to increase the specificity of the tested AIE compound towards selected cell lines.},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {New approaches for milk quality monitoring},

author = {Cristina Giannattasio and Rosaria Cozzolino and Alessandra Di Concilio and Sofia Pellecchia and Sabato D’Auria and Angela Pennacchio},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Milk is a fundamental food source, valued globally for its rich nutritional content, including proteins, fats, vitamins, and essential minerals that benefit all age groups. Monitoring milk quality is critical in order to maintain food safety and human health[1].

Therefore, there is an urgent need for the development of fast, sensitive, reliable and cost-effective methods and sensor systems for milk quality monitoring.

Volatile Organic Compounds (VOCs) are important indicators of milk quality and origin, reflecting factors such as animal metabolism, diet, geographic region, and grazing conditions, which can differentiate milk samples from various farming systems or regions. There is high evidence that the VOCs profile of milk from grazing cattle is different from that of cows fed indoor [2}.

The aim of this work was to design and to develop an innovative “impinger” biosensor that utilizes Molecular Recognition Elements (MRE) such as Odorant-Binding Proteins (OBPs) to detect VOCs in milk, to differentiate milk samples from intensive versus extensive farming systems. The impinger captures the VOCs released from milk, which then are collected in a liquid phase. This liquid sample was transferred to the biosensor chamber, where OBPs bind selectively to VOCs. The binding event triggers a Förster Resonance Energy Transfer (FRET) signal that is proportional to the VOCs concentration, allowing the quantification of specific compounds and it is indicative of milk quality. The binding between pOBP and VOCs was investigated using Head Space Solid-Phase Microextraction coupled with Gas Chromatography-Mass Spectrometry (HS-SPME/GC-MS), confirming the specificity and efficiency of OBP-VOC interactions. This research provides a foundation for future advancements in biosensor technology for food quality monitoring.

This real-time approach provides a sensitive and cost-effective solution for VOCs monitoring. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Synergy in antiproliferative activity between various modulators of cellular cholesterol homeostasis in colon cancer cells},

author = {Maria Błaszczyk and Anna Palko-Łabuz and Kamila Środa-Pomianek and Olga Wesołowska},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Cholesterol (Chol) is an important component of cellular membranes affecting their fluidity and permeability. Its altered levels are associated with various pathologies, e.g., atherosclerosis and cardiovascular disease [1]. Additionally, disturbed Chol and lipid homeostasis are observed in cancer [2].

The interaction of simvastatin, the anti-hyperlipidemic drug with three antidepressant and antipsychotic drugs was studied. All of them are known to affect Chol homeostasis. Statins are inhibitors of main enzyme in Chol biosynthesis, HMG-CoA reductase [3]. Common side effect of antipsychotic drugs is weight gain accompanied by metabolic syndrome [8]. Some antipsychotics also up-regulate expression of genes engaged in Chol biosynthesis, being controlled by SREBP transcription factor [4]. SREBP is main regulator of lipid homeostasis. Additionally, statins and many antipsychotic drugs possess anticancer activity [5]. Disruption of Chol homeostasis has been suggested to be responsible for their cytotoxicity [5].

Antiproliferative activity of imipramine, flupentixol, and trifluperazine was corroborated in two human colon cancer cell lines. All studied compounds exhibited significant degree of selectivity towards cancerous versus non-cancerous cells.

The activity of the studied drugs combined with low concentration of simvastatin was also investigated. Synergistic interaction between them was discovered and analyzed in detail with the use of mathematical models (Chou-Talalay & HSA method).

To better understand mechanism of drugs’ cytotoxicity their influence on cellular level of Chol was studied and the most active drugs turned out to decrease its amount. The studied drugs induced also the enhancement of expression of SREBP-controlled genes encoding HMG-CoA reductase and LDL receptor. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Polystyrene nanoparticles and their epigenetic effects in human peripheral blood mononuclear cells},

author = {Kinga Malinowska and Kateryna Tarhonska and Marek Foksiński and Ewa Jabłońska and Edyta Reszka and Ewelina Zarakowska and Daniel Gackowski and Karolina Górecka and Aneta Balcerczyk and Bożena Bukowska and Paulina Sicińska},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {The potential effect of PS-NPs on the molecular markers and determinants of the carcinogenesis process was investigated. We studied the effects of non-functionalized polystyrene nanoparticles (PS-NPs) of varying diameters (29 nm, 44 nm, and 72 nm) on specific epigenetic modifications and gene expression profiles in human peripheral blood mononuclear cells (PBMCs) in vitro. We used concentrations ranging from 0.001 to 100 μg/mL and cells were incubated for 24 hours. We analysed the level of 5-metyl-2'-deoxycytidine (5-mdC) by mass spectrometry method, methylation in the promoter regions of suppressor genes TP53 (P53), CDKN2A (P16), and CDKN1A (P21) and proto-oncogenes (CCND1, BCL2, BCL6), along with their expression profile by Real-Time PCR assays.

The results revealed no significant changes in global DNA methylation/demethylation levels in PBMCs after short-term exposure to non-functionalized PS-NPs. None of the PS-NPs caused a change in the methylation pattern of the promoter regions of the TP53, CDKN2A, CDKN1A, CCND1, BCL2 and BCL6 genes. However, gene profiling indicated that PS-NPs with a diameter of 29 nm and 44 nm altered the expression of TP53 gene. The smallest PS-NPs with a diameter of 29 nm increased the expression of the TP53 gene at a concentration of 10 μg/mL, while PS-NPs with a diameter of 44 nm did so at a concentration of 100 μg/mL. An increase in the expression of the CDKN2A gene was also observed when PBMCs were exposed to PS-NPs with 29 nm in diameter at the highest concentration. Our study elucidates the limited epigenetic effect of PS-NPs on human PBMCs under the examined conditions. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Transport mechanism of paracetamol in polymer nanocomposite MATERIALS},

author = {Justyna Strankowska and Małgorzata Grzywińska and Ewelina Łęgowska and Michał Strankowski},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

publisher = {Polish Biophysical Society and Adam Mickiewicz University},

address = {ul. Uniwersytetu Poznanskiego 2, 61-614 Poznan},

abstract = {In this work, the new class of hybrid materials - polyurethane/Cloisite® 30B (PU/PEO Cloisite® 30B) nanocomposite hydrogel systems for paracetamol drug delivery were studied. We present the swelling and release properties of these drug delivery systems depending on clay - Cloisite® 30B (CLO) concentration, as well as crosslinking agent type. The transport mechanism, swelling and release processes of the active substance in nanocomposite matrix, were studied using gravimetric and UV-Vis spectroscopic methods. Swelling and release processes depend on the amount of clay nanoparticles in these systems and the degree of crosslinking of PU/PEG/Cloisite® 30B hydrogel nanocomposites. The presence of clay causes, on the one hand, a reduction in free volumes in the polymer matrices, making the swelling process less effective, on the other hand, the high swelling and self-aggregation

behavior of Cloisite® 30B and the interactions of paracetamol both with it and with the matrix, cause a change in the transport mechanism from anomalous diffusion to Fickian-like diffusion. It has been also proven that in the case of modification of polymer matrices with nanoparticles, the appropriate selection of their concentration is crucial, due to the

potential possibility of controlling the swelling and release processes in drug delivery patches [1].

Analyzing the data obtained from the steady-state spectroscopic and gravimetric measurements one can state that exceeding a certain critical value of the nanofiller concentration (0.5%), leads to its aggregation, which causes decreasing free volumes in the system and decreasing of swelling, in the case of more cross-linked systems but also relaxation rates decrease due to the barrier effect and increase due to the swelling of the aggregated clay. The relaxation rate increases slightly with increasing paracetamol concentration in the

presence of nanoparticles and decreases when they are not present in the system, because clays promote swelling of the polymer matrix. Release relaxation rates increase with increasing CLO concentration, the nanoparticles presence in the system increase the efficiency of hydrogel expansion during the swelling processes and by clay-matrix interaction. In the case of too high concentration of Cloisite® 30B, the diffusion rate decreases due to the barrier effect corelated with clay aggregation, because the diffusion pathlength

increases and causes decrease of drug concentration gradient. Diffusion coefficients of paracetamol molecules in the release process increase with increasing concentration of Cloisite® 30B in all matrices, diffusion coefficients Dshort_app and Dlong_app [2] are of the same order and are higher for long-time approximation (Fig.1). .....},

type = {Poster},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Revealing cancer dynamics: The application of pyrimidinebased fluorescent compound for analyzing organelle accumulation with no toxicity in glioma and colon cancer cells},

author = {Kamila Środa-Pomianek and Lech Sznitko and Daria Zając and Aleksandra Dupla and Martyna Perz and Olga Wesołowska and Anna Palko-Łabuz},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {This study presents a newly developed pyrimidine-based compound that exhibits imaging capabilities without cytotoxic effect. Fluorescence-based compounds represent a powerful tool for non-invasive bioimaging of living systems in real time, which is crucial for analyzing cancer dynamics. Contemporary cancer treatment, including glioma and colon cancer, relies on advanced diagnostic methods and therapies tailored to individual patient needs [1].

Fluorescent compounds, particularly those containing nitrogen heteroatoms, have the ability to accumulate in different parts of biological tissue, and their exceptional optoelectronic properties and biocompatibility make them useful for applications in cancer studies.

In our research, we synthesized 4,4’-(2,2’(pyrimidine-4,6-diyl)bis(hydrazine-2-yl-1ylidene)bis (methanylylidene)) bis (N,N-diphenylaniline) employing a two-step synthesis, where the key step was the hydrazone condensation reaction. Optical characterization of the compound was performed using UV-Vis spectrometers, revealing interesting properties dependent on the molecule's environment, including polarity and pH. The absence of toxicity was confirmed using the sulforhodamine B (SRB) assay, a widely accepted method for evaluating cell viability. This non-toxic profile is a significant advantage, especially for applications involving mitochondrial fluorescence visualization, where maintaining cellular integrity is crucial. Additionally, mitochondrial membrane potential assays were conducted as part of the study. This aspect of the investigation was essential to check the absence of cytotoxic effects suggested by preliminary viability tests. Since mitochondria play a central role in cellular energy metabolism and apoptotic signaling, assessing mitochondrial function provides a more sensitive and mechanistically relevant indicator of toxicity. Given that many hydrazone and pyrimidine derivatives can pose cytotoxic risks, the development of a safe compound suitable for live-cell imaging represents a meaningful step forward. Importantly, the studied pyrimidine based fluorescent compound does not induce changes in mitochondrial membrane potential, preserving the functional state of mitochondria during imaging.

Hydrazone-based probes are especially useful due to their ability to detect cations, anions, aldehydes, and ketones, which can be used to label biomolecules such as oxidized proteins or saccharides. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Identification of volatile organic compounds (VOCs) as markers of goat cheeses ripening: perspectives and applicability in biosensor design},

author = {G. Ferrara and Concetta Montagnese and Rosaria Cozzolino and Sabato D’Auria},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Ripening is a complex and dynamic process that determines the final organoleptic characteristics of cheese. The production of volatile organic compounds (VOCs) is among the most informative parameters related to maturation. These metabolites are generated by the enzymatic degradation of lipids, proteins, and carbohydrates, through proteolysis, lipolysis, and the metabolism of citrate and lactate 1,2. VOCs, besides playing a fundamental role in defining the flavour characteristics of cheese, act as molecular indicators of specific stages of maturation. Accurate analytical information about cheese ripening is essential for several applications: optimization of the ripening conditions, early intervention in case of defects, and tailoring of the development of new cheese varieties with customize aromatic profiles 3. In this perspective, the identification of one or more volatile components as specific biomarkers of ripening will allow for a rapid, and non-destructive control of the cheese production processes 4.

For this purpose, goat cheeses were analysed by headspace solid-phase micro extraction (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS) to characterize the VOCs profile and evaluate its evolution during the maturation process. The first objective was to identify VOCs that could be utilized as molecular markers capable of discriminating between early, intermediate and advanced ripening cheese stages 5. This selection represents the first step towards the design of a dedicated biosensor, capable of selectively detecting these VOCs. The biosensor will be designed to operate in real conditions, ensuring sensitivity, specificity and robustness. This can contribute to the automation and improvement of quality in the dairy value chain. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Differential analysis of male and female cucumber lines at mRNA and miRNA levels},

author = {Maksymilian Pisz and Szymon Turek and Agnieszka Skarzyńska-Łyżwa and Agata Głuchowska and Magdalena Pawełkowicz},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Cucumber (Cucumis sativus) serves as a model species for investigating the processes related to sex determination in plants [1]. While the development of flower organs is known to be regulated at both mRNA and microRNA (miRNA) levels, the precise interactions governing these processes remain insufficiently understood [2].

This study aimed to elucidate regulatory pathways involved in flower development by analyzing differentially expressed genes (DEGs) identified via RNA sequencing (RNA-seq) of flower buds from three cucumber lines: 2gg (gynoecious), Gy3 (gynoecious and weak) and B10 (monoecious) [3]. In parallel, small RNA (sRNA) sequencing was employed to identify differentially expressed miRNAs and their corresponding target genes. Gene ontology (GO) enrichment analysis was performed to study the molecular functions and biological processes associated with these genes. Additionally, protein-protein interaction network analysis was conducted to identify key pathways affected by DEGs. As a result, several candidate genes were highlighted as potentially crucial regulators of sex determination in cucumber flowers.

These findings contribute to a better understanding of the complex genetic and epigenetic mechanisms involved in floral development. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {Fluorescence Correlation Spectroscopy assay to detect the presence of toxic microcystin-LR molecules in water},

author = {Anatonio Varriale and G. Ferrara, Alessandro Capo and Sabato D’Auria},

issn = {2084-1892},

year  = {2025},

date = {2025-06-25},

urldate = {2025-06-25},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

abstract = {Fluorescence correlation spectroscopy (FCS) is a quantitative technique that allows the determination of concentration and diffusion properties of fluorescently labeled species with single-molecule sensitivity. In a standard confocal optical set-up, a laser is focused on a diffraction-limited spot using a high numerical aperture objective lens. The emitted light is collected through a confocal pinhole, defining a small observation volume (femtoliters). When the fluorescent species diffuse through this observation volume, the photons emitted are recorded over time, generating fluorescence fluctuations1. These fluctuations can be analyzed using two different methods: autocorrelation analysis (AC) and photon counting histogram analysis (PCH). In the case of the autocorrelation analysis, it is possible to study the diffusion rate and concentration of the fluorescent species over time, while the photon counting histogram analysis (PCH) allows us to quantify the concentration and molecular brightness of the species based on the analysis of their amplitude 1. Several studies have shown the effectiveness of FCS to address fundamental questions in biology2-5. Furthermore, some studies have used this technique in sensing to identify specific molecules, such as allergens, toxins and antibiotics, in various matrices6,7. This method relies on the variation of the fluorescence fluctuation, associated with the formation of a molecular complex between a specific biomolecule (antibody, binding protein, peptide, etc.) and its fluorescent target analyte, in the absence and presence of the analyte. In this study, we present the application of the FCS method to detect the presence of toxic microcystins-LR (MC-LR) in water. For this purpose, we used a fluorescence-labeled conjugate (BSA-MC-LR) and monoclonal antibody to develop a competitive assay for the sensitive and accurate detection of MC-LR. The obtained results will be presented and discussed. ...},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{PlenaryLectures2025_3,

title = {Conjugates of DNA and boron clusters as building blocks for nanoparticle carriers of therapeutic nucleic acids with gene silencing activities},

author = {Krzysztofa Śmiałkowski and Katarzyna Bednarska-Szczepaniak and Katarzyna Ebenryter-Olbińska and Katarzyna Kulik and Justyna Suwara and Gabriela Gajek and Lidia Fiedorowicz and Aleksander Foryś and Bohumir Grűner and Barbara Nawrot and Zbigniew Leśnikowski },

issn = {2084-1892},

year  = {2025},

date = {2025-06-24},

urldate = {2025-06-24},

booktitle = {Abstracts of the XIX Congress of the Polish Biophysical Society (PTBF)},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

issue = {44},

publisher = {Polish Biophysical Society and Adam Mickiewicz University},

address = {ul. Uniwersytetu Poznanskiego 2, 61-614 Poznan},

abstract = {Despite thousands of chemotherapeutic drugs approved for clinical practice, there are still many unmet needs in the prevention and treatment of many diseases. The need to fill this never-shrinking gap is driving search for new drugs, both in the traditional chemotherapeutic category and in newer generation drugs such as biotherapeutics. Still another, emerging recently drug modality are therapeutic nucleic acids (TNAs) that have the potential to address many currently unmet by chemotherapeutic and biotherapeutic drugs needs [1-3]. However, even though already there are over 20 TNAs on the market, TNAs are still a new technology that faces challenges and problems that must to be solved. They include difficulties with delivery, susceptibility to degradation by nucleases, rapid clearance from the body, off-target effects and others. In quest to find solutions to these problems, a number of technologies are tested, one of them is nanotechnology.

For several years, our laboratory has researched modifying nucleic acids with boron clusters, a molecular cages with unique and advantageous properties [4], and studied their applications as probes for molecular diagnostics, boron carriers for boron neutron capture therapy (BNCT) and therapeutic nucleic acids. Continuing involvement in the very hot research area of TNAs we are focusing now on nanoparticle carriers of TNAs based on composites of DNA-oligomers and boron clusters.....

},

type = {Plenar lecture},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{PlenaryLectures2025_4,

title = {Cell Response Driven by Surface chemistry and Charges on electrospun polymer NANOfibers},

author = {Urszula Stachewicz},

issn = {2084-1892},

year  = {2025},

date = {2025-06-24},

urldate = {2025-06-24},

booktitle = {Abstracts of the XIX Congress of the Polish Biophysical Society (PTBF)},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

issue = {44},

publisher = {Polish Biophysical Society and Adam Mickiewicz University},

address = {ul. Uniwersytetu Poznanskiego 2, 61-614 Poznan},

abstract = {Surface charge is a critical determinant in cell–biomaterial interactions, influencing adhesion, proliferation, and regenerative signaling. Electrospun polymer scaffolds, known for their high surface-area-to-volume ratio, are promising candidates for biomedical applications such as tissue engineering, drug delivery, and skin regeneration [1-2]. However, precise control over surface charge during electrospinning remains underexplored.

A comprehensive investigation of distinct mechanisms to modulate surface potential in electrospun fibers was performed. We examined the influence of polymer chain orientation induced by alternating voltage polarity during electrospinning [3]. We also explored material diffusion between core and shell phases in coaxial fibers [4]. Most recently, we evaluated the impact of incorporating two-dimensional conductive nanomaterials—reduced graphene oxide (rGO) and titanium carbide MXenes (Ti₃C₂Tₓ)—on surface potential of polymer fibers [5].We demonstrate that reversing the polarity of the applied voltage during electrospinning significantly alters the surface potential of poly(L-lactic acid) (PLLA), polycaprolactone (PCL), poly(vinylidene fluoride) (PVDF) fibers, as shown by Kelvin probe force microscopy (KPFM), and this modulation directly enhances osteoblast adhesion [6]. Additionally, we explore how diffusion between core and shell materials affects fibre surface chemistry and charge distribution, shedding light on a previously unexamined factor in coaxial electrospinning. Moreover, we show that embedding rGO and MXene nanosheets within polymer matrices modifies surface potential and bioactivity, even when these nanomaterials are not surface-exposed.

Scaffolds were systematically characterized using KPFM, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and zeta potential measurements to correlate surface properties with cellular responses. Confocal laser scanning microscopy (CLSM) with AiryScan was employed to visualize focal adhesion complexes, offering insights into how surface charge governs outside-in and inside-out signaling pathways.

In summary, our findings highlight the pivotal role of scaffold surface potential in mediating cellular responses and underscore the importance of tailored electrospun fibre design to accelerate tissue regeneration processes. ....

},

key = {4},

type = {Plenar lecture},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{PlenaryLectures2025_5,

title = {Reengineering of a Bacterial Compartment INTO Tailorable Bionanomaterials},

author = {Yusuke Azuma},

year  = {2025},

date = {2025-06-24},

urldate = {2025-06-24},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

issue = {44},

publisher = {Polish Biophysical Society and Adam Mickiewicz University},

address = {ul. Uniwersytetu Poznanskiego 2, 61-614 Poznan},

abstract = {Self-assembling protein cages are naturally occurring hollow nanostructures with inherent capabilities for compartmentalizing and organizing biomolecules, making them promising candidates for a wide range of bioengineering applications. A key challenge in this field is precisely controlling their assembly and morphology to tailor function for specific applications. Understanding the molecular mechanisms underlying the polymorphic protein assemblies provides a basis for designing ones with the desired morphology.

Our recent work elucidates fundamental principles governing the self-assembly of a model cage-forming protein, Aquifex aeolicus lumazine synthase (AaLS) [1,2]. An engineered,  circularly permuted variant of AaLS exhibits remarkable structural plasticity, assembling into diverse, hollow spherical and cylindrical structures in response to subtle changes in ionic strength (Fig. 1). Cryogenic electron microscopy (cryo-EM) reveals that these structures are composed entirely of pentameric subunits, and the dramatic cage-to-tube transformation is mediated by an α-helix domain that is untethered from its native position by circular permutation, a key structural determinant for controlling assembly [3]. The utility of this controlled assembly is demonstrated by the stabilization of labile biomolecules produced in host cells and their efficient retrieval outside biological contexts, showcasing cpAaLS as a versatile platform for nanoscale manipulation and cargo delivery [4].

Our results highlight the potential for broad advancements across biotechnological applications, ranging from bioproduction to nanomedicine. Furthermore, the structural insights gained into the assembly mechanisms and the role of circular permutation in dictating morphology provide a valuable framework for the rational design of novel nanomaterials with tailored properties....

},

key = {5},

type = {Plenar lecture},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{PlenaryLectures2025_6,

title = {Nanocarrier-based delivery of rose bengal for enhanced photodynamic therapy of basal cell carcinoma},

author = {Barbara Klajnert-Maculewicz and Monika Dąbrzalska and Krzysztof Sztandera and Michał Gorzkiewicz},

issn = {2084-1892},

year  = {2025},

date = {2025-06-24},

urldate = {2025-06-24},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

issue = {44},

publisher = {Polish Biophysical Society and Adam Mickiewicz University},

address = {ul. Uniwersytetu Poznanskiego 2, 61-614 Poznan},

abstract = {Photodynamic therapy (PDT) is an innovative approach to skin cancer treatment, offering a targeted and less invasive alternative to conventional radiotherapy and chemotherapy while minimizing adverse effects. PDT relies on the activation of a photosensitizing agent by light of a specific wavelength in the presence of molecular oxygen, generating singlet oxygen and reactive oxygen species that induce cell death. The effectiveness of PDT is largely dependent on the properties of the photosensitizer, which can face limitations such as poor solubility, low tumor specificity, and inadequate accumulation at the target site. To overcome these challenges, nanocarriers have been explored as effective delivery systems [1].

This study focuses on the potential of dendrimers [2, 3], dendrimersomes [4], and polymersomes [5] as nanoscale carriers for rose Bengal - a photosensitizer. We evaluated four distinct nanocarriers based on key parameters, including spectral properties, encapsulation efficiency, singlet oxygen generation, intracellular transport, and phototoxicity. By systematically comparing these nanosystems, we assessed their ability to enhance the therapeutic efficacy of rose Bengal in PDT for basal cell carcinoma.

Our findings highlight that the interaction mechanism between rose Bengal and the nanocarrier plays a crucial role in determining its photodynamic efficiency. Among the studied delivery methods, phosphorus dendrimers demonstrated the highest efficacy, significantly improving singlet oxygen production, intracellular transport, and phototoxic effects [2]. These results demonstrate the potential of nanocarrier-based delivery strategies for optimizing PDT outcomes in basal cell carcinoma treatment ....

},

key = {6},

type = {Plenar lecture},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{PlenaryLectures2025_7,

title = {Peptidooliposomal formulations for antiviral therapies},

author = {Olga Michel and Aleksandra Kaczorowska and Lucyna Matusewicz and Kliwia Piórkowska and Marlena Golec and Wiktoria Fus and Kazimierz Kuliczkowski and Aleksander F. Sikorski and Aleksander Czogalla},

year  = {2025},

date = {2025-06-24},

urldate = {2025-06-24},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

issue = {44},

publisher = {Polish Biophysical Society and Adam Mickiewicz University},

address = {ul. Uniwersytetu Poznanskiego 2, 61-614 Poznan},

abstract = {There is an urgent need for the development of new antiviral formulations because humanity is constantly confronted with a range of new, potentially lethal viruses originating from different reservoirs. These formulations should prevent the progression of viremia and disease while being relatively easily adaptable to specific needs and guarantee resistance to mutational changes [1]. Such a goal can be achieved with appropriately functionalized nanoparticles such as liposomes [2].

Our aim was to develop effective therapeutic formulations against coronavirus and influenza infections. Using maleimide-functionalized liposomes as a platform for the immobilization, stabilization and delivery of short peptide sequences with high affinity to viral particles, we focused on fine-tuning the lipid composition and size calibration procedure to achieve selective binding, high homogeneity and excellent long-term stability. We show that the stability of the formulations depends not only on their chemical composition, but more importantly on the particle size calibration technique used in their preparation. The approach based on the widely used extrusion through membranes of defined pores makes it possible to achieve long-term stability. However, a stable and highly homogeneous formulation could also be produced by a high-throughput microfluidic homogenization technique [3]. In a first step towards the creation of nanostructures that recognize and deactivate viral particles, we have demonstrated the robustness and specificity of the prepared nanostructures by measuring the biomolecular interactions using microscale thermophoresis. The inhibitory effect of the obtained preparations against the infection of susceptible cells by pseudoviruses (lentiviruses bearing genes encoding luciferase-conjugated SARS-Cov-2 proteins) was also confirmed. Furthermore, our nanoformulations showed no toxicity either in vitro or in vivo. 

Thus, the developed nanocarrier technology can serve as a platform for virus-inactivating nanoparticles, and its versatility can be ensured by replacing individual components. ...

},

key = {7},

type = {Plenar lecture},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{Radoń2025,

title = {Hotter together: boosting hyperthermia efficiency through inter-particle interactions},

author = {Adrian Radoń and Agnieszka Ciuraszkiewicz and Piotr Piotrowski and Andrzej Hudecki and Grzegorz Litwinienko and Anna Lewińska and Maciej Wnuk},

issn = {2084-1892},

year  = {2025},

date = {2025-06-24},

urldate = {2025-06-24},

booktitle = {Abstracts of the XIX Congress of the Polish Biophysical Society (PTBF)},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

issue = {44},

publisher = {Polish Biophysical Society and Adam Mickiewicz University},

address = {ul. Uniwersytetu Poznanskiego 2, 61-614 Poznan},

abstract = {In recent years, magnetic nanoparticles (MNPs) have attracted growing interest as anticancer agents within the scientific and medical fields. A prominent example is NanoTherm® therapy, primarily applied in treating gliomas, which utilizes magnetically induced hyperthermia [1]. In this therapy, an alternating magnetic field generates heat through Néel and Brownian motions and hysteresis losses (in some instances) of magnetic particles [2].

The chemical composition, size, and shape of the MNPs significantly influence the efficiency of magnetically induced hyperthermia. As such, these parameters are systematically tested to optimize performance [3]. One of the most critical factors is the dispersion concentration of the magnetic particles (Cmagn). However, the relationship between Cmagn and the specific absorption rate (SAR) is nonlinear. Moreover, the resulting temperature increase (ΔT) does not directly correlate with SAR values. These phenomena were recently explored in depth by Kim et al. [4], who linked them to inter-particle interactions in magnetic fluids at varying concentrations.

In this study, we focus on these inter-particle interactions by varying the dispersion concentration and modifying the initial nanoparticle interactions during the synthesis process. Tailored synthesis methods allow us to produce a variety of nanoparticle structures, including ultrafine and highly agglomerated particles, large cuboidal particles, multicore MNPs, and ultrafine particles embedded in a polymer matrix.

Each nanoparticle type exhibits distinct behavior when analyzing SAR as a function of concentration. Interestingly, even nanoparticles with identical chemical compositions and similar size and shape can show significantly different heating efficiencies (see Table 1). These variations are attributed to inter-particle interactions, which can be precisely adjusted during synthesis using different surface modifiers ....

},

key = {8},

type = {Plenar lecture},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}

@conference{nokey,

title = {From MDa to kDa – across the scale of the cryoEM SPA analysis of biological molecules},

author = {Artur P. Biela},

issn = {2084-1892},

year  = {2025},

date = {2025-06-24},

urldate = {2025-06-24},

booktitle = {Abstracts of the XIX Congress of the Polish Biophysical Society (PTBF)},

journal = {Current Topics in Biophysics},

volume = {44 (suppl.A)},

publisher = {Polish Biophysical Society and Adam Mickiewicz University},

address = {ul. Uniwersytetu Poznanskiego 2, 61-614 Poznan},

abstract = {Cryo-electron microscopy has gained considerable attention and has proven to be a powerful tool in structural biology. For the past years, scientists worldwide tried to push the boundaries of the technique and used it in their research projects to solve structures of all kinds of biological molecules. Here, in this presentation, I would like to show that size does matter, but there is a way to overcome this issue. Starting from large protein assemblies like synthetic cages of paradoxical geometry derived from bacterial enzyme, virus-like particles of different shapes and sized (both: spherical and rod-like) being in the MDa range (Figure 1), and going down to relatively small multimeric enzymes in complexes with their partners (both: proteins and small molecules), and finally finishing at sub 30-kDa particles like free tRNA molecule, being the smallest molecule so far reconstructed with cryoEM. Despite the broad range of molecular masses, we were able to show some important features of the molecules investigated like the symmetry of the assemblies, paradoxical arrangements of the building blocks, draw some rules about the symmetry breaking, describe the composition of the complexes, decipher the mechanism of their action, get to know the nature of the crucial bonds or even the influence of the introduced modifications on the structure’s rigidity (to some extend)(Figure 2)....},

type = {Plenar lecture},

keywords = {},

pubstate = {published},

tppubtype = {conference}

}