+Search query
-Structure paper
Title | Cryo-EM structure of a type IV secretion system. |
---|---|
Journal, issue, pages | Nature, Vol. 607, Issue 7917, Page 191-196, Year 2022 |
Publish date | Jun 22, 2022 |
Authors | Kévin Macé / Abhinav K Vadakkepat / Adam Redzej / Natalya Lukoyanova / Clasien Oomen / Nathalie Braun / Marta Ukleja / Fang Lu / Tiago R D Costa / Elena V Orlova / David Baker / Qian Cong / Gabriel Waksman / |
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 ...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. |
External links | Nature / PubMed:35732732 / PubMed Central |
Methods | EM (single particle) |
Resolution | 2.6 - 9.2 Å |
Structure data | EMDB-12707: O-Layer C14 at 2.58A - Local refinement with C14 symmetry of the O-layer of the outer membrane core complex from the fully-assembled R388 type IV secretion system. EMDB-12708: I-Layer C16 at 3.08A - Local refinement with C16 symmetry of I-layer of the outer membrane core complex from the fully-assembled R388 type IV secretion system. EMDB-12709: Stalk C1 at 3.71A - Local refinement without symmetry of the Stalk complex from the fully-assembled R388 type IV secretion system. EMDB-12715: IMC-Arches C6 at 8.33A - Refinement with C6 symmetry of the Inner Membrane Complex (IMC) with the Arches from the fully-assembled R388 type IV secretion system. EMDB-12716: Trimer of dimers TrwK/VirB4unbound C1 at 4.14A - Refinement without symmetry of TrwK/VirB4unbound trimer of dimers complex (with Hcp1) from the R388 type IV secretion system. EMDB-12717: Dimer TrwK/VirB4unbound C1 at 3.49A - Local refinement without symmetry of the TrwK/VirB4unbound dimer complex from the R388 type IV secretion system. EMDB-12933: IMC protomer C1 at 3.75A - Local refinement without symmetry of the inner membrane complex (IMC) protomer from the fully-assembled R388 type IV secretion system. EMDB-13765: OMCC C1 at 3.28A - Refinement without symmetry of the outer membrane core complex (O- and I-layer) from the fully-assembled R388 type IV secretion system. EMDB-13766: Ab Initio model for IMC-Arches-Stalk from the fully-assembled R388 type IV secretion system determined by cryo-EM. EMDB-13767: IMC-Arches-Stalk C1 at 6.18A - Refinement of the IMC, Arches and Stalk complex without symmetry from the fully-assembled R388 type IV secretion system. EMDB-13768: Stalk C5 at 3.28A - Local refinement with C5 symmetry of the Stalk complex from the fully-assembled R388 type IV secretion system. |
Source |
|
Keywords | MEMBRANE PROTEIN / type IV secretion system / type 4 secretion system / T4SS / O-layer / core complex / outer membrane complex / inner membrane / R388 plasmid / conjugation / bacterial secretion / secretion / secretion system / protein complex / VirB10 / VirB9 / VirB7 / TrwE / TrwF / TrwH / I-layer / stalk / stalk complex / VirB5 / VirB6 / TrwJ / TrwI / IMC / inner membrane complex / arches / periplasmic / VirB3 / VirB4 / VirB8 / TrwM / TrwK / TrwG / ATPase / Hcp / dimer |