Identification of new members within suites of amphiphilic marine siderophores

Marine bacterial isolates Vibrio sp. HC0601C5 and Halomonas meridiana str. HC4321C1 were isolated off the coast of southern California and were found to produce an expanded suite of previously identified amphiphilic siderophores. Specifically two new members of the amphibactin family, amphibactins S and T, which have a C14:1 omega-7 fatty acid and a saturated C12 fatty acid, respectively, were produced by Vibrio sp. HC0601C5. These siderophores are produced in addition to a number of previously described amphibactins and are excreted into the culture supernatant. Two new members of the aquachelin family of siderophores, aquachelins I and J, which have an hydroxylated C12 fatty acid and a saturated C10 fatty acid, respectively, were produced by Halomonas meridiana str. HC4321C1. These four new siderophores are more hydrophilic than their previously reported relatives, aquachelins A-D and the amphibactin suite of siderophores.