title: Siderophore production of a periplasmic transport binding protein kinase gene defective mutant of Magnetospirillum magneticum AMB-1.
abstract: A non-magnetic mutant, NMA61, of the magnetic bacterium Magnetospirillum magneticum AMB-1 was generated by transposon mutagenesis to identify genes involved in magnetosome synthesis. The genomic region of NMA61 interrupted by a Mini-Tn5 transposon was analyzed. The transposon was inserted in an open reading frame (ORF) coding for a periplasmic transport binding protein kinase gene homologue. Three adjacent ORFs and a promoter were identified upstream, indicating that the sequences comprised an operon. Phenotype characterizations showed that the growth inhibition imposed by the exogenous non-assimilable iron chelator nitrilotriacetate was relieved in wild type but not in NMA61, by the addition of the isolated wild type siderophore. Higher concentration of siderophores accumulated in the culture medium of NMA61 than in wild type. These data suggest that the interrupted periplasmic transport binding protein kinase gene homologue is required for siderophore transport into M. magneticum AMB-1.
authors.affiliation: Department of Biotechnology, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588, Japan.
authors.forename: Ronie J
authors.initials: RJ
authors.lastname: Calugay
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Okamura
authors.forename: Aris Tri
authors.initials: AT
authors.lastname: Wahyudi
authors.forename: Haruko
authors.initials: H
authors.lastname: Takeyama
authors.forename: Tadashi
authors.initials: T
authors.lastname: Matsunaga
mesh_terms: D000595:Amino Acid Sequence; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D005290:Ferric Compounds / Q000378:metabolism*; D007501:Iron / Q000493:pharmacokinetics*; D042201:Magnetospirillum / Q000201:enzymology* / Q000235:genetics* / Q000648:ultrastructure; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D033902:Periplasmic Binding Proteins / Q000235:genetics / Q000378:metabolism; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D017262:Siderophores / Q000235:genetics / Q000378:metabolism*; D013329:Structure-Activity Relationship
chemical_list: D002352:Carrier Proteins; D005290:Ferric Compounds; D033902:Periplasmic Binding Proteins; D011994:Recombinant Proteins; D017262:Siderophores; D007501:Iron; D011494:Protein Kinases