Zapraszamy do udziału w seminarium Wydziału Inżynierii Materiałowej i Fizyki Technicznej Politechniki Poznańskiej oraz Oddziału Poznańskiego Polskiego Towarzystwa Fizycznego, które odbędzie się 13 kwietnia 2023 r. o godz. 11:45. Pani mgr inż. Emilia Krok wygłosi seminarium w formie zdalnej pt. „The fascinating world of microbes – the development of model bacterial cell membranes”. (link do pokoju Seminarium: https://emeeting.put.poznan.pl/eMeeting/rys-gup-9is).
The fascinating world of microbes – the development of model bacterial cell membranes
Emilia Kroka,b, Mareike Stephanaa, Rumiana Dimovaa, Lukasz Piatkowskib
aMax Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany
bPoznan University of Technology, Faculty of Materials Engineering and Technical Physics, Institute of Physics, Piotrowo 3, 60-965 Poznan, Poland
Abstract
Reconstruction of accurate yet simplified mimetic models of cell membranes is a very challenging goal of synthetic biology. To date, most of the research focuses on the development of eukaryotic cell membranes, while the reconstitution of their prokaryotic counterparts has not been fully addressed, and the proposed models do not reflect well the complexity of bacterial cell envelopes. Here, we describe the reconstitution of biomimetic bacterial membranes with an increasing level of complexity, developed from binary and ternary lipid mixtures. Giant unilamellar vesicles composed of phosphatidylcholine (PC) and phosphatidylethanolamine (PE); PC and phosphatidylglycerol (PG); PE and PG; PE, PG, and cardiolipin (CA) at varying molar ratios were successfully prepared by the electroformation method. Each of the proposed mimetic models focuses on reproducing specificmembrane features such as membrane charge, curvature, leaflets asymmetry, or the presence of phase separation. GUVs were characterized in terms of size distribution, surface charge, and lateral organization. Finally, the developed models were tested against the lipopeptide antibiotic daptomycin. The obtained results showed a clear dependency of daptomycin binding efficiency on the amount of negatively charged lipid species present in the membrane. We anticipate that the models proposed here can be applied not only in antimicrobial testing but also serve as platforms for studying fundamental biological processes in bacteria as well as their interaction with physiologically relevant biomolecules.
