title: The HtrA family of serine proteases.
abstract: HtrA, also known as DegP and probably identical to the Do protease, is a heat shock-induced serine protease that is active in the periplasm of Escherichia coli. Homologues of HtrA have been described in a wide range of bacteria and in eukaryotes. Its chief role is to degrade misfolded proteins in the periplasm. Substrate recognition probably involves the recently described PDZ domains in the C-terminal half of HtrA and, we suspect, has much in common with the substrate recognition system of the tail-specific protease, Prc (which also possesses a PDZ domain). The expression of htrA is regulated by a complex set of signal transduction pathways, which includes an alternative sigma factor, RpoE, an anti-sigma factor, RseA, a two-component regulatory system, CpxRA, and two phosphoprotein phosphatases, PrpA and PrpB. Mutations in the htrA genes of Salmonella, Brucella and Yersinia cause decreased survival in mice and/or macrophages, and htrA mutants can act as vaccines, as cloning hosts and as carriers of heterologous antigens.
authors.affiliation: Department of Medical Microbiology, St Bartholomew's and the Royal London School of Medicine and Dentistry, UK. m.pallen@qmw.ac.uk
authors.forename: M J
authors.initials: MJ
authors.lastname: Pallen
authors.forename: B W
authors.initials: BW
authors.lastname: Wren
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001419:Bacteria; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D006360:Heat-Shock Proteins; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D033903:Periplasmic Proteins; D016415:Sequence Alignment; D012697:Serine Endopeptidases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D006360:Heat-Shock Proteins; D033903:Periplasmic Proteins; C061682:DegP protease; D012697:Serine Endopeptidases