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bioRxiv · 10.1101/718072

Structure of the bacterial flagellar rotor MS-ring: a minimum inventory/maximum diversity system

Johnson, S.·Fong, Y. H.·Deme, J.·Furlong, E.·Kuhlen, L.·Lea, S.
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Abstract

The bacterial flagellum is a complex, self-assembling, nanomachine that confers motility on the cell. Despite great variation across species, all flagella are ultimately constructed from a helical propellor attached to a motor embedded in the inner membrane. The motor consists of a series of stator units surrounding a central rotor made up of two ring complexes, the MS-ring and the C-ring. Despite many studies, high resolution structural information is still completely lacking for the MS-ring of the rotor, and proposed mismatches in stoichiometry between the two rings have long provided a source of confusion for the field. We here present structures of the Salmonella MS-ring, revealing an unprecedented level of inter- and intra-chain symmetry variation that provides a structural explanation for the ability of the MS-ring to function as a complex and elegant interface between the two main functions of the flagellum, protein secretion and rotation.

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Johnson, S., Fong, Y. H., Deme, J., Furlong, E., Kuhlen, L., Lea, S.. 2019-07-30. Structure of the bacterial flagellar rotor MS-ring: a minimum inventory/maximum diversity system. https://doi.org/10.1101/718072

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