Identification and characterization of Aeromonas hydrophila genes encoding the outer membrane receptor of ferrioxamine B and an AraC-type transcriptional regulator.
We found that, under iron-limiting conditions, Aeromonas hydrophila ATCC 7966(T) could utilize the xenosiderophore desferrioxamine B (DFOB) for growth by inducing the expression of its own outer membrane receptor. Two consecutive genes, desR and desA, were selected as candidates involved in DFOB utilization. The presence of the ferric-uptake regulator boxes in their promoters suggested that these genes are under iron-dependent regulation. Mutation of desA, a gene that encodes the outer membrane receptor of ferrioxamine B, disrupted the growth of the amonabactin-deficient mutant in the presence of DFOB. β-Galactosidase reporter assays and reverse transcriptase-quantitative PCR demonstrated that desR, a gene that encodes an AraC-like regulator homolog is required for the induction of desA transcription in the presence of DFOB and under iron-limiting conditions. The functions of desA and desR were analyzed using complementation experiments. Our data provided evidence that DesA is powered primarily by the TonB2 system.
['Funahashi|Tatsuya|T|', 'Tanabe|Tomotaka|T|', 'Maki|Jun|J|', 'Miyamoto|Katsushiro|K|', 'Tsujibo|Hiroshi|H|', 'Yamamoto|Shigeo|S|']
D016980:Aeromonas hydrophila D000595:Amino Acid Sequence D051777:AraC Transcription Factor D001425:Bacterial Outer Membrane Proteins D003676:Deferoxamine D004734:Energy Metabolism D005290:Ferric Compounds D007501:Iron D005810:Multigene Family D009876:Operon D010641:Phenotype D017384:Sequence Deletion D013379:Substrate Specificity D014158:Transcription, Genetic
Aeromonas hydrophila outer membrane receptor desferrioxamine B AraC-type regulator TonB