Abstract

Type IX secretion system (T9SS), exclusively present in the Bacteroidetes phylum, has been studied mainly in Flavobacterium johnsoniae and Porphyromonas gingivalis. Among the 18 genes, essential for T9SS function, a group of four, porK-N (P. gingivalis) or gldK-N (F. johnsoniae) belongs to a co-transcribed operon that expresses the T9SS core membrane complex. The central component of this complex, PorM (or GldM), is anchored in the inner membrane by a trans-membrane helix and interacts through the outer membrane PorK-N complex. There is a complete lack of available atomic structures for any component of T9SS, including the PorKLMN complex. Here we report the crystal structure of the GldM and PorM periplasmic domains. Dimeric GldM and PorM, each contain four domains of ~180-Å length that span most of the periplasmic space. These and previously reported results allow us to propose a model of the T9SS core membrane complex as well as its functional behavior.

Details

Title
Type IX secretion system PorM and gliding machinery GldM form arches spanning the periplasmic space
Author
Leone, Philippe 1 ; Roche, Jennifer 1 ; Vincent, Maxence S 2 ; Tran, Quang Hieu 1 ; Desmyter, Aline 1 ; Cascales, Eric 2   VIAFID ORCID Logo  ; Kellenberger, Christine 1 ; Cambillau, Christian 1   VIAFID ORCID Logo  ; Roussel, Alain 1 

1  Architecture et Fonction des Macromolécules Biologiques, Aix-Marseille Université, Marseille, France; Architecture et Fonction des Macromolécules Biologiques, Centre National de la Recherche Scientifique, Marseille, France 
2  Laboratoire d’Ingénierie des Systèmes Macromoléculaires, Institut de Microbiologie de la Méditerranée, Centre National de la Recherche Scientifique (UMR7255), Aix-Marseille Université, Marseille Cedex 20, France 
Pages
1-8
Publication year
2018
Publication date
Jan 2018
Publisher
Nature Publishing Group
e-ISSN
20411723
Source type
Scholarly Journal
Language of publication
English
DOI
https://doi.org/10.1038/s41467-017-02784-7
ProQuest document ID
1992654880
Copyright
© 2018. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.