title: Fatty acid hydrolysis of acyl marinobactin siderophores by Marinobacter acylases.
abstract: The marine bacteria Marinobacter sp. DS40M6 and Marinobacter nanhaiticus D15-8W produce a suite of acyl peptidic marinobactin siderophores to acquire iron under iron-limiting conditions. During late-log phase growth, the marinobactins are hydrolyzed to form the marinobactin headgroup with release of the corresponding fatty acid tail. The bntA gene, a homologue of the Pseudomonas aeruginosa pyoverdine acylase gene, pvdQ, was identified from Marinobacter sp. DS40M6. A bntA knockout mutant of Marinobacter sp. DS40M6 produced the suite of acyl marinobactins A-E, without the usual formation of the marinobactin headgroup. Another marinobactin-producing species, M. nanhaiticus D15-8W, is predicted to have two pvdQ homologues, mhtA and mhtB. MhtA and MhtB have 67% identical amino acid sequences. MhtA catalyzes hydrolysis of the apo-marinobactin siderophores as well as the quorum sensing signaling molecule, dodecanoyl-homoserine lactone. In contrast to hydrolysis of the suite of apo-marinobactins by MhtA, hydrolysis of the iron(III)-bound marinobactins was not observed.
authors.affiliation: Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106-9510, United States.
authors.forename: Michelle P
authors.initials: MP
authors.lastname: Kem
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Naka
authors.forename: Akira
authors.initials: A
authors.lastname: Iinishi
authors.forename: Margo G
authors.initials: MG
authors.lastname: Haygood
authors.forename: Alison
authors.initials: A
authors.lastname: Butler
mesh_terms: D015107:4-Butyrolactone / Q000031:analogs & derivatives / Q000378:metabolism; D000215:Acylation; D000581:Amidohydrolases / Q000235:genetics / Q000378:metabolism*; D001059:Apoproteins / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D056148:Chromatography, Reverse-Phase; D005227:Fatty Acids / Q000378:metabolism*; D055786:Gene Knockout Techniques; D006868:Hydrolysis; D007501:Iron / Q000378:metabolism; D053520:Marinobacter / Q000201:enzymology* / Q000235:genetics; D009154:Mutation; D009842:Oligopeptides / Q000378:metabolism*; D017262:Siderophores / Q000737:chemistry / Q000378:metabolism*
chemical_list: D001059:Apoproteins; D001426:Bacterial Proteins; D005227:Fatty Acids; D009842:Oligopeptides; D017262:Siderophores; C088386:homoserine lactone; D007501:Iron; D000581:Amidohydrolases; C019665:amidase; D015107:4-Butyrolactone