Structure and membrane affinity of new amphiphilic siderophores produced by Ochrobactrum sp. SP18.

TitleStructure and membrane affinity of new amphiphilic siderophores produced by Ochrobactrum sp. SP18.
Publication TypeJournal Article
Year of Publication2006
AuthorsMartin JD, Ito Y, Homann VV, Haygood MG, Butler A
JournalJ Biol Inorg Chem
Volume11
Issue5
Pagination633-41
Date Published2006 Jul
ISSN0949-8257
KeywordsAcetylation, Citric Acid, Dimyristoylphosphatidylcholine, Iron, Light, Lysine, Membranes, Molecular Structure, Ochrobactrum, Photochemistry, Phylogeny, Siderophores, Ultraviolet Rays
Abstract

The coastal alpha-proteobacterium Ochrobactrum sp. SP18 produces a suite of three citrate-derived, cell-associated amphiphilic siderophores, ochrobactins A-C. The ochrobactins are composed of a citric acid backbone amide-linked to two lysine residues. Each epsilon-amine of lysine is hydroxylated and acylated forming two hydroxamic acid moieties. One of the acylated appendages of each ochrobactin is (E)-2-decenoic acid. The other acylated appendages for ochrobactins A-C are (E)-2-octenoic acid, octanoic acid and (E)-2-decenoic acid, respectively. The ferric ochrobactin complexes are photoreactive in UV light, producing an oxidized ligand with loss of 46 mass units that can still coordinate Fe(III). The relative partitioning of the apo-ochrobactins, Fe(III) ochrobactins and Fe(III) photoproducts into 1,2-dimyristoyl-sn-glycero-3-phosphocholine vesicles is presented. The ochrobactins are the first example of aerobactin-based siderophores with two fatty acid appendages produced in a suite with varying acyl appendage lengths.

DOI10.1007/s00775-006-0112-y
Alternate JournalJ. Biol. Inorg. Chem.
PubMed ID16791646
Grant ListGM38130 / GM / NIGMS NIH HHS / United States