Spatial Organization of Biological Fuctions | BPS Thematic Meeting

Spatial Organization of Biological Functions Meeting

Poster Abstracts

4-POS Board 4 EXPLORING PORE-FORMATION KINETICS BY ANTIMICROBIAL PEPTIDES IN GIANT UNILAMELLAR VESICLES Sonam Raghav 1 ; Devansh Kaushik 1 ; Bibhu R Sarangi 2 ; Olivia Vincent 2 ; Anupam Bandyopadhyay 3 ; Veerendra K Sharma 5 ; Archana Mukherjee 4,5 ; Sajal K Ghosh 1 ; 1 Shiv Nadar Institution of Eminence, Physics, Dadri, Gautam Buddha Nagar, India 5 Bhabha Atomic Research Centre, Radiopharmaceuticals Division, Mumbai, India Antimicrobial-resistant bacteria pose a significant threat to humans, prompting extensive research into developing new antimicrobial peptides (AMPs). The kinetics of pore formation by AMPs in a vesicle system is an important physical parameter to decide its efficiency in controlling bacterial growth. In the present study, we investigate the kinetics of two ubiquicidin based AMPs in giant unilamellar vesicles (GUVs), namely, UBI (29-41) and its modified variant, UBI-2-APBA. The rate of pore formation was monitored by tracking decay in fluorescence intensity over time, which was further modeled theoretically. Data indicated that UBI (29-41) promotes rapid pore formation in GUVs composed of zwitterionic (PC) and anionic (PG) lipids, while UBI-2-APBA exhibits enhanced pore-forming activity in the presence of lysyl phosphatidylglycerol (Lys PG) in the lipid membrane. The structural nature of the pores was investigated by the small-angle X-ray scattering (SAXS) technique on multilamellar vesicles. The model data fitting suggests that there is no permanent static pore formed in the lipid membrane; rather, there are flip-flop-induced transient pores in the membrane. The study concludes that the boronated UBI-2-APBA shows strong activity with the Lys PG-containing membranes, establishing it as an effective antimicrobial peptide towards antibiotic-resistant bacteria. 2 IIT Palakkad, Physics, Palakkad, India 3 IIT Ropar, Chemistry, Rupnagar , India 4 Homi Bhabha National Institute, Physics, Mumbai, India

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