title: The putative iron transport system SitABCD encoded on SPI1 is required for full virulence of Salmonella typhimurium.
abstract: Salmonella typhimurium is an invasive pathogen that causes diseases ranging from mild gastroenteritis to enteric fever. During the infection process, S. typhimurium induces a number of virulence genes required to circumvent host defences and/or acquire nutrients in the host. We have used the in vivo expression technology (IVET) system to select for S. typhimurium genes that are induced after invasion of a murine cultured cell line. We have characterized a putative iron transporter in Salmonella pathogenicity island 1, termed sitABCD. The sitABCD operon is induced under iron-deficient conditions in vitro and is repressed by Fur. This locus is induced in the animal specifically after invasion of the intestinal epithelium. We show that a sit null mutant is significantly attenuated in BALB/c mice, suggesting that SitABCD plays an important role in iron acquisition in the animal.
authors.affiliation: Department of Microbiology, University of Illinois, B103 CLSL, 601 S. Goodwin Avenue, Urbana, IL 61801, USA.
authors.forename: A
authors.initials: A
authors.lastname: Janakiraman
authors.forename: J M
authors.initials: JM
authors.lastname: Slauch
mesh_terms: D000818:Animals; D001692:Biological Transport; D002352:Carrier Proteins / Q000235:genetics*; D005798:Genes, Bacterial; D007501:Iron / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D009154:Mutation; D009876:Operon; D012480:Salmonella Infections / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D012486:Salmonella typhimurium / Q000235:genetics / Q000472:pathogenicity*; D014774:Virulence
chemical_list: D002352:Carrier Proteins; D007501:Iron