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bioRxiv · 10.1101/2020.12.05.413195

Molecular structure of the intact bacterial flagellar basal body

Johnson, S.·Furlong, E.·Deme, J.·Nord, A. L.·Caesar, J.·Chevance, F.·Berry, R.·Hughes, K. T.·Lea, S. M.
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Abstract

Bacterial flagella self-assemble a strong, multi-component drive shaft that couples rotation in the inner membrane to the microns-long flagellar filament that powers bacterial swimming in viscous fluids. We here present structures of the intact Salmonella flagellar basal body, solved using cryo-electron microscopy to resolutions between 2.2 and 3.7 [A]. The structures reveal molecular details of how 173 protein molecules of 13 different types assemble into a complex spanning two membranes and a cell wall. The helical drive shaft at one end is intricately interwoven with the inner membrane rotor component, and at the other end passes through a molecular bearing that is anchored in the outer membrane via interactions with the lipopolysaccharide. The in situ structure of a protein complex capping the drive shaft provides molecular insight into the assembly process of this molecular machine.

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Johnson, S., Furlong, E., Deme, J., Nord, A. L., Caesar, J., Chevance, F., Berry, R., Hughes, K. T., Lea, S. M.. 2020-12-06. Molecular structure of the intact bacterial flagellar basal body. https://doi.org/10.1101/2020.12.05.413195

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