7O3T

I-layer structure (TrwF/VirB9NTD, TrwE/VirB10NTD) of the outer membrane core complex from the fully-assembled R388 type IV secretion system determined by cryo-EM.

Summary for 7O3T

• Entry DOI: 10.2210/pdb7o3t/pdb
• EMDB information: 12708
• Descriptor: TrwE protein, TrwF protein (2 entities in total)
• Functional Keywords: type iv secretion system, type 4 secretion system, t4ss, i-layer, core complex, outer membrane complex, r388 plasmid, conjugation, bacterial secretion, secretion, secretion system, protein complex, virb10, virb9, trwe, trwf, membrane protein
• Biological source: Escherichia coli; More
• Total number of polymer chains: 32
• Total formula weight: 1155093.94

Authors

Mace, K.,Vadakkepat, A.K.,Lukoyanova, N.,Waksman, G. (deposition date: 2021-04-03, release date: 2022-06-22, Last modification date: 2024-07-10)

Primary citation

Mace, K.,Vadakkepat, A.K.,Redzej, A.,Lukoyanova, N.,Oomen, C.,Braun, N.,Ukleja, M.,Lu, F.,Costa, T.R.D.,Orlova, E.V.,Baker, D.,Cong, Q.,Waksman, G.
Cryo-EM structure of a type IV secretion system.
Nature, 607:191-196, 2022

PubMed Abstract: Bacterial conjugation is the fundamental process of unidirectional transfer of DNAs, often plasmid DNAs, from a donor cell to a recipient cell. It is the primary means by which antibiotic resistance genes spread among bacterial populations. In Gram-negative bacteria, conjugation is mediated by a large transport apparatus-the conjugative type IV secretion system (T4SS)-produced by the donor cell and embedded in both its outer and inner membranes. The T4SS also elaborates a long extracellular filament-the conjugative pilus-that is essential for DNA transfer. Here we present a high-resolution cryo-electron microscopy (cryo-EM) structure of a 2.8 megadalton T4SS complex composed of 92 polypeptides representing 8 of the 10 essential T4SS components involved in pilus biogenesis. We added the two remaining components to the structural model using co-evolution analysis of protein interfaces, to enable the reconstitution of the entire system including the pilus. This structure describes the exceptionally large protein-protein interaction network required to assemble the many components that constitute a T4SS and provides insights on the unique mechanism by which they elaborate pili.

PubMed: 35732732
DOI: 10.1038/s41586-022-04859-y

Experimental method

ELECTRON MICROSCOPY (3.1 Å)