Iron acquisition in the marine actinomycete genus Salinispora is controlled by the desferrioxamine family of siderophores.
Many bacteria produce siderophores for sequestration of growth-essential iron. Analysis of the Salinispora genomes suggests that these marine actinomycetes support multiple hydroxamate- and phenolate-type siderophore pathways. We isolated and characterized desferrioxamines (DFOs) B and E from all three recognized Salinispora species and linked their biosyntheses in S. tropica CNB-440 and S. arenicola CNS-205 to the des locus through PCR-directed mutagenesis. Gene inactivation of the predicted iron-chelator biosynthetic loci sid2-4 did not abolish siderophore chemistry. Additionally, these pathways could not restore the native growth characteristics of the des mutants in iron-limited media, although differential iron-dependent regulation was observed for the yersiniabactin-like sid2 pathway. Consequently, this study indicates that DFOs are the primary siderophores in laboratory cultures of Salinispora.
Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA 92093, USA.
Alexandra A
AA
Roberts
Andrew W
AW
Schultz
Roland D
RD
Kersten
Pieter C
PC
Dorrestein
Bradley S
BS
Moore
D001483:Base Sequence; D003676:Deferoxamine / Q000378:metabolism*; D023061:Gene Order; D005798:Genes, Bacterial; D007501:Iron / Q000378:metabolism*; D008848:Micromonosporaceae / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D005810:Multigene Family; D016297:Mutagenesis, Site-Directed; D016415:Sequence Alignment; D017262:Siderophores / Q000235:genetics / Q000378:metabolism*
D017262:Siderophores; D007501:Iron; D003676:Deferoxamine