title: Mutual stabilization of the XcpZ and XcpY components of the secretory apparatus in Pseudomonas aeruginosa.
abstract: Protein secretion in gram-negative bacteria is often dependent on the general secretory pathway (GSP). In Pseudomonas aeruginosa, this system requires at least 12 Xcp (Gsp) proteins, which are proposed to constitute a multiprotein complex localized in the bacterial envelope. Hitherto, little was known about the mutual interactions between Xcp proteins. In this study, mutants affected in the xcpZ gene encoding a bitopic inner-membrane protein were analysed to investigate the role of this protein in the architecture of the secretory machinery. The absence of XcpZ resulted in a decreased amount of XcpY. Reciprocally, XcpZ was not detectable in a xcpY mutant, demonstrating a mutual stabilization of these two proteins. These results strongly suggest that XcpZ and XcpY interact within the functional secretory apparatus.
authors.forename: Gérard
authors.initials: G
authors.lastname: Michel
authors.forename: Sophie
authors.initials: S
authors.lastname: Bleves
authors.forename: Geneviève
authors.initials: G
authors.lastname: Ball
authors.forename: Andrée
authors.initials: A
authors.lastname: Lazdunski
authors.forename: Alain
authors.initials: A
authors.lastname: Filloux
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D004926:Escherichia coli / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D009154:Mutation; D011485:Protein Binding; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000502:physiology*
chemical_list: D001426:Bacterial Proteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; C066761:xcpY protein, Pseudomonas aeruginosa; C066762:xcpZ protein, Pseudomonas aeruginosa