title: Bacterial type III secretion systems: specialized nanomachines for protein delivery into target cells.
abstract: One of the most exciting developments in the field of bacterial pathogenesis in recent years is the discovery that many pathogens utilize complex nanomachines to deliver bacterially encoded effector proteins into target eukaryotic cells. These effector proteins modulate a variety of cellular functions for the pathogen's benefit. One of these protein-delivery machines is the type III secretion system (T3SS). T3SSs are widespread in nature and are encoded not only by bacteria pathogenic to vertebrates or plants but also by bacteria that are symbiotic to plants or insects. A central component of T3SSs is the needle complex, a supramolecular structure that mediates the passage of the secreted proteins across the bacterial envelope. Working in conjunction with several cytoplasmic components, the needle complex engages specific substrates in sequential order, moves them across the bacterial envelope, and ultimately delivers them into eukaryotic cells. The central role of T3SSs in pathogenesis makes them great targets for novel antimicrobial strategies.
authors.affiliation: Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut 06536; email: jorge.galan@yale.edu.
authors.forename: Jorge E
authors.initials: JE
authors.lastname: Galán
authors.forename: Maria
authors.initials: M
authors.lastname: Lara-Tejero
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Marlovits
authors.forename: Samuel
authors.initials: S
authors.lastname: Wagner
mesh_terms: D000818:Animals; D001419:Bacteria / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D001424:Bacterial Infections / Q000382:microbiology*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D058947:Bacterial Secretion Systems; D006801:Humans; D021381:Protein Transport
chemical_list: D001426:Bacterial Proteins; D058947:Bacterial Secretion Systems
keywords: bacterial pathogenesis; molecular machines; protein secretion