Structural bases for F plasmid conjugation and F pilus biogenesis in Escherichia coli
Abstract
Bacterial "sex," or conjugation, is a central mechanism underlying the proliferation of antibiotic resistance. Despite the discovery of conjugation by F plasmids in Escherichia coli over seven decades ago, we have only now visualized the F-encoded transfer channel and F pilus-associated platforms in the E. coli cell envelope by cryoelectron tomography. The channel supports plasmid transfer or assembly of F pili, which remarkably upon synthesis are deposited onto alternative basal structures around the cell surface. The F plasmid transfer system is a paradigm for the bacterial type IV secretion system (T4SS) superfamily. Consequently, the F-encoded structures are broadly informative of mechanisms underlying the biogenesis and function of type IV secretion machines and associated conjugative pili.
- Publication:
-
Proceedings of the National Academy of Science
- Pub Date:
- July 2019
- DOI:
- 10.1073/pnas.1904428116
- Bibcode:
- 2019PNAS..11614222H