Berlin 2024 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

BP: Fachverband Biologische Physik

BP 22: Bacterial Biophysics II

BP 22.6: Vortrag

Mittwoch, 20. März 2024, 16:30–16:45, H 0112

Reciprocity of flagellar polymorphism and cell-body motion during tumbling of an E. coli — •Derek Cyrus Gomes¹, Holger Stark², and Tapan Chandra Adhyapak¹ — ¹Indian Institute of Science Education and Research (IISER) Tirupati, Tirupati, India — ²Institut für Theoretische Physik, Technische Universität Berlin

The study of the dynamics of E. Coli has proven to be an extremely challenging problem due to the complex mechanisms underlying its motion. One such aspect of the dynamics involves E.Coli’s abrupt change of swimming direction during the tumbling events. The event results from the reverse rotation of one of the flagella, making it leave the flagellar bundle and causing, at the same time, an overall change in the bacterium’s motion. It has been shown experimentally that during the tumbling event, the reverse-rotated flagellum undergoes transitions among several of its stable structures known as the polymorphic forms. While polymorphic transitions accompany a tumbling event, their necessity and influence over the tumbling statistics are unknown. In this work, we numerically probe the interplay of the cell body dynamics and flagellar polymorphism during a tumbling event. We find a reciprocal response between the two: while the polymorphic transitions do affect the cell body’s tumbling dynamics, in turn, the cell-body motion can arrest the growth of the polymorphic forms. We present our results in light of the observed tumbling statistics, revealing new insights to understand the experimental observations. We also investigate the role of hydrodynamic interactions and shear flow in the aforementioned phenomena.

Keywords: E. Coli; Polymorphism; tumbling; shear