title: On the path to uncover the bacterial type II secretion system.
abstract: Gram-negative bacteria have evolved several secretory pathways to release enzymes or toxins into the surrounding environment or into the target cells. The type II secretion system (T2SS) is conserved in Gram-negative bacteria and involves a set of 12 to 16 different proteins. Components of the T2SS are located in both the inner and outer membranes where they assemble into a supramolecular complex spanning the bacterial envelope, also called the secreton. The T2SS substrates transiently go through the periplasm before they are translocated across the outer membrane and exposed to the extracellular milieu. The T2SS is unique in its ability to promote secretion of large and sometimes multimeric proteins that are folded in the periplasm. The present review describes recently identified protein-protein interactions together with structural and functional advances in the field that have contributed to improve our understanding on how the type II secretion apparatus assembles and on the role played by individual proteins of this highly sophisticated system.
authors.affiliation: Laboratoire d'Ingénierie des Systèmes Macromoléculaires (CNRS-LISM-UPR 9027), Aix-Marseille Universités, Institut de Microbiologie de la Méditerranée, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20, France.
authors.forename: Badreddine
authors.initials: B
authors.lastname: Douzi
authors.forename: Alain
authors.initials: A
authors.lastname: Filloux
authors.forename: Romé
authors.initials: R
authors.lastname: Voulhoux
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics; D058947:Bacterial Secretion Systems; D002462:Cell Membrane / Q000737:chemistry; D010861:Fimbriae, Bacterial / Q000737:chemistry; D005798:Genes, Bacterial; D006090:Gram-Negative Bacteria / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D008958:Models, Molecular; D005810:Multigene Family; D019897:Periplasm / Q000737:chemistry; D017510:Protein Folding; D025941:Protein Interaction Mapping; D021381:Protein Transport; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D058947:Bacterial Secretion Systems; D000251:Adenosine Triphosphatases