The 94th Annual Meeting of Japanese Society for Bacteriology

Presentation information

Evening Workshop

[EWS1] The second "Big Bang" of bacterial flagellar researches

Tue. Mar 23, 2021 7:00 PM - 9:00 PM Channel 1

Conveners: Tohru Minamino (Osaka University), Seiji Kojima (Nagoya University)

[EWS1-4] Mechanisms of substrate selectivity and protein secretion during assembly of the bacterial flagellum

○Marc Erhardt (Institute for Biology, Humboldt Univ. Berlin)

How organisms construct complex functional units from simple building blocks remains poorly understood. The flagellum is the most sophisticated extracellular structure known in bacteria and a prime example of how nature succeeds in assembling sophisticated functional machines in simple and elegant, yet robust ways. The major external components of the flagellum assemble successively. A type-III protein secretion system (T3SS) at the base of the flagellum transports its building blocks across the inner membrane with a remarkable speed of several thousand amino acids per second, which is several orders of magnitude faster than protein export in other pore-based protein channels.
However, how T3SSs are able to transport proteins at such a high rate while preventing the leakage of small molecules remains a rather big mystery. In addition, how the bacteria coordinate the simultaneous assembly of multiple flagella and select the appropriate substrate proteins to ensure correct hierarchy and stoichiometry of the exported building blocks remains elusive.
During my talk, I will discuss recent advances in our understanding of the substrate selectivity and protein export mechanisms of the bacterial flagellum.