SKM 2021 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
BP: Fachverband Biologische Physik
BP 4: Posters Biological Physics
BP 4.6: Poster
Thursday, September 30, 2021, 11:15–12:15, P
Swimming vesicles propelled by flagellated bacteria in membrane tubes — •Lucas Le Nagard1, Aidan Brown1, Alexander Morozov1, Angela Dawson1, Vincent Martinez1, Margarita Staykova2, and Wilson Poon1 — 1The University of Edinburgh, United Kingdom — 2Durham University, United Kingdom
Recent simulation studies have predicted that giant unilamellar vesicles submitted to a collection of local internal forces should display enhanced fluctuations and a fascinating diversity of shape changes, from the formation of membrane tubes to deformations leading to vesicle division. Experimental investigation of those phenomena, based on the encapsulation of self-propelled particles or swimming bacteria into giant lipid vesicles, has only recently started. Such minimal systems can be used to study the interactions between an active suspension and a confining (deformable) boundary. They should also help deepen the understanding of biological processes where membrane deformation under local forcing is important. In this work, we encapsulate motile Escherichia coli bacteria in low-tension giant lipid vesicles. We observe that the bacteria apply local forces on the membrane, deforming it to generate membrane tubes reminiscent of those seen in eukaryotic cells infected by Listeria monocytogenes. Strikingly, these bacteria-enclosing tubes can propel the vesicles. We show that the propulsive force arises from a tight coupling between the bacteria’s well-bundled flagella and the membrane tubes, which become rotating helices turning the initially passive vesicles into active micro-swimmers.