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Bacterial flagellar motor PL-ring disassembly subcomplexes are widespread and ancient.

ABSTRACT: The bacterial flagellum is an amazing nanomachine. Understanding how such complex structures arose is crucial to our understanding of cellular evolution. We and others recently reported that in several Gammaproteobacterial species, a relic subcomplex comprising the decorated P and L rings persists in the outer membrane after flagellum disassembly. Imaging nine additional species with cryo-electron tomography, here, we show that this subcomplex persists after flagellum disassembly in other phyla as well. Bioinformatic analyses fail to show evidence of any recent horizontal transfers of the P- and L-ring genes, suggesting that this subcomplex and its persistence is an ancient and conserved feature of the flagellar motor. We hypothesize that one function of the P and L rings is to seal the outer membrane after motor disassembly.

SUBMITTER: Kaplan M

PROVIDER: S-EPMC7183148 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Bacterial flagellar motor PL-ring disassembly subcomplexes are widespread and ancient.

Kaplan Mohammed M Sweredoski Michael J MJ Rodrigues João P G L M JPGLM Tocheva Elitza I EI Chang Yi-Wei YW Ortega Davi R DR Beeby Morgan M Jensen Grant J GJ

Proceedings of the National Academy of Sciences of the United States of America 20200402 16

The bacterial flagellum is an amazing nanomachine. Understanding how such complex structures arose is crucial to our understanding of cellular evolution. We and others recently reported that in several Gammaproteobacterial species, a relic subcomplex comprising the decorated P and L rings persists in the outer membrane after flagellum disassembly. Imaging nine additional species with cryo-electron tomography, here, we show that this subcomplex persists after flagellum disassembly in other phyla ...[more]

PMID: 32241888

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