VirB7 and VirB9 Interactions Are Required for the Assembly and Antibacterial Activity of a Type IV Secretion System

Autor(es)

Oliveira, Luciana Coutinho ; Souza, Diorge Paulo ; Oka, Gabriel Umaji ; Lima, Filipe da Silva ; Oliveira, Ronaldo Junio ; Favaro, Denize Cristina ; Wienk, Hans ; Boelens, Rolf ; Farah, Chuck Shaker ; Salinas, Roberto Kopke

• Tipo de documento: Artigo Científico
• Fonte: Structure; v. 24, n. 10, p. 1707-1718, OCT 4 2016.
• Citações Web of Science: 3

Resumo

The type IV secretion system (T4SS) from the phytopathogen Xanthomonas citri (Xac) is a bactericidal nanomachine. The T4SS core complex is a ring composed of multiple copies of VirB7-VirB9-VirB10 subunits. Xac-VirB7 contains a disordered N-terminal tail (VirB7(NT)) that recognizes VirB9, and a C-terminal domain (VirB7(CT)) involved in VirB7 self-association. Here, we show that VirB7(NT) forms a short beta strand upon binding to VirB9 and stabilizes it. A tight interaction between them is essential for T4SS assembly and antibacterial activity. Abolishing VirB7 self-association or deletion of the VirB7 C-terminal domain impairs this antibacterial activity without disturbing T4SS assembly. These findings reveal protein interactions within the core complex that are critical for the stability and activity of a T4SS. (AU)

• Processo FAPESP: 13/17883-2 - Estrutura e dinâmica do trocador Na+/Ca2+ de Drosophila melanogaster
• Beneficiário: Roberto Kopke Salinas
• Linha de fomento: Auxílio à Pesquisa - Regular
• Processo FAPESP: 11/07777-5 - Sinalização por c-di-GMP e o sistema de secreção de macromoléculas do tipo IV em Xanthomonas citri
• Beneficiário: Shaker Chuck Farah
• Linha de fomento: Auxílio à Pesquisa - Temático