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Cryo-EM structure of the bacteria-killing type IV secretion system core complex from Xanthomonas citri.

ABSTRACT: Type IV secretion (T4S) systems form the most common and versatile class of secretion systems in bacteria, capable of injecting both proteins and DNAs into host cells. T4S systems are typically composed of 12 components that form 2 major assemblies: the inner membrane complex embedded in the inner membrane and the core complex embedded in both the inner and outer membranes. Here we present the 3.3 Å-resolution cryo-electron microscopy model of the T4S system core complex from Xanthomonas citri, a phytopathogen that utilizes this system to kill bacterial competitors. An extensive mutational investigation was performed to probe the vast network of protein-protein interactions in this 1.13-MDa assembly. This structure expands our knowledge of the molecular details of T4S system organization, assembly and evolution.

SUBMITTER: Sgro GG

PROVIDER: S-EPMC6264810 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Cryo-EM structure of the bacteria-killing type IV secretion system core complex from Xanthomonas citri.

Sgro Germán G GG Costa Tiago R D TRD Cenens William W Souza Diorge P DP Cassago Alexandre A Coutinho de Oliveira Luciana L Salinas Roberto K RK Portugal Rodrigo V RV Farah Chuck S CS Waksman Gabriel G

Nature microbiology 20181022 12

Type IV secretion (T4S) systems form the most common and versatile class of secretion systems in bacteria, capable of injecting both proteins and DNAs into host cells. T4S systems are typically composed of 12 components that form 2 major assemblies: the inner membrane complex embedded in the inner membrane and the core complex embedded in both the inner and outer membranes. Here we present the 3.3 Å-resolution cryo-electron microscopy model of the T4S system core complex from Xanthomonas citri, ...[more]

PMID: 30349081

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