title: Autotransporter secretion: varying on a theme.
abstract: Autotransporters are widely distributed among Gram-negative bacteria. They can have a large variety of functions and many of them have a role in virulence. They are synthesized as large precursors with an N-terminal signal sequence that mediates transport across the inner membrane via the Sec machinery and a translocator domain that mediates the transport of the connected passenger domain across the outer membrane to the bacterial cell surface. Like integral outer membrane proteins, the translocator domain folds in a β-barrel structure and requires the Bam machinery for its insertion into the outer membrane. After transport across the outer membrane, the passenger may stay connected via the translocator domain to the bacterial cell surface or it is proteolytically released into the extracellular milieu. Based on the size of the translocator domain and its position relative to the passenger in the precursor, autotransporters are divided into four sub-categories. We review here the current knowledge of the biogenesis, structure and function of various autotransporters.
authors.affiliation: Section Molecular Microbiology, Department of Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands. j.grijpstra@uu.nl
authors.forename: Jan
authors.initials: J
authors.lastname: Grijpstra
authors.forename: Jesús
authors.initials: J
authors.lastname: Arenas
authors.forename: Lucy
authors.initials: L
authors.lastname: Rutten
authors.forename: Jan
authors.initials: J
authors.lastname: Tommassen
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D058947:Bacterial Secretion Systems; D002462:Cell Membrane / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D006090:Gram-Negative Bacteria / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D021381:Protein Transport
chemical_list: D001426:Bacterial Proteins; D058947:Bacterial Secretion Systems; D026901:Membrane Transport Proteins
keywords: Autotransporter; Bam complex; Chaperone; Outer membrane; Protein secretion