title: A gene cluster involved in the biosynthesis of vanchrobactin, a chromosome-encoded siderophore produced by Vibrio anguillarum.
abstract: Vibrio anguillarum serotype O2 strains produce a catechol siderophore named vanchrobactin, which has been identified as N-[N'-(2,3-dihydroxybenzoyl)-arginyl]-serine. This work describes a chromosomal region that harbours the genetic determinants necessary for the biosynthesis of vanchrobactin. The authors have identified the genes involved in 2,3-dihydroxybenzoic acid (DHBA) biosynthesis (vabA, vabB and vabC) and activation (vabE), and a gene (vabF) encoding a non-ribosomal peptide synthetase, which is putatively involved in the assembly of the siderophore components. Also described are the identification and characterization of genes encoding a putative vanchrobactin exporter (vabS) and a siderophore esterase (vabH). In-frame deletion mutants in vabA, vabB, vabC, vabE, vabF and vabH were impaired for growth under conditions of iron limitation, and the analysis of culture supernatants by chrome azurol-S and cross-feeding assays showed almost no production of siderophores in any of the vabABCEF mutants. In addition, deletion mutations of vabA, vabB and vabC abolished production of DHBA, as assessed by chemical and biological analyses. Complementation of each mutant with the corresponding gene provided in trans confirmed the involvement of this gene cluster in the biosynthesis of DHBA and vanchrobactin in V. anguillarum strain RV22. Based on chemical and genetic data, and on published models for other catechol siderophores, a model for vanchrobactin biosynthesis is proposed.
authors.affiliation: Department of Microbiology and Parasitology, Institute of Aquaculture and Faculty of Biology, University of Santiago de Compostela, Campus Sur, Santiago de Compostela 15782, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Balado
authors.affiliation: Department of Microbiology and Parasitology, Institute of Aquaculture and Faculty of Biology, University of Santiago de Compostela, Campus Sur, Santiago de Compostela 15782, Spain.
authors.forename: Carlos R
authors.initials: CR
authors.lastname: Osorio
authors.affiliation: Department of Microbiology and Parasitology, Institute of Aquaculture and Faculty of Biology, University of Santiago de Compostela, Campus Sur, Santiago de Compostela 15782, Spain.
authors.forename: Manuel L
authors.initials: ML
authors.lastname: Lemos
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics; D002876:Chromosomes, Bacterial / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004798:Enzymes / Q000235:genetics; D004950:Esterases / Q000235:genetics; D017353:Gene Deletion; D005798:Genes, Bacterial; D005816:Genetic Complementation Test; D062385:Hydroxybenzoates / Q000378:metabolism; D007501:Iron / Q000378:metabolism; D008954:Models, Biological; D008969:Molecular Sequence Data; D005810:Multigene Family; D010453:Peptide Synthases / Q000235:genetics; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D017262:Siderophores / Q000096:biosynthesis* / Q000235:genetics*; D014733:Vibrio / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D004269:DNA, Bacterial; D004798:Enzymes; D062385:Hydroxybenzoates; D017262:Siderophores; C009135:2,3-dihydroxybenzoic acid; D007501:Iron; D004950:Esterases; D010453:Peptide Synthases; C104385:non-ribosomal peptide synthase