Abstract
Desferrioxamine B (DFOB, a terrestrial bacterial siderophore) has been used in experiments on waters from iron‐replete areas of the oceans to manipulate the levels of iron available to the biota. Addition of DFOB complexes the available iron (III) and has been suggested to render this complexed iron unavailable to marine microorganisms. We have identified a marine bacterium belonging to the genus Vibrio that produces the siderophore desferrioxamine G. Desferrioxamine G, another known terrestrial siderophore, is very similar in structure to DFOB, differing only by the substitution of a terminal methyl group by a propionic acid moiety. These results could affect the interpretation of DFOB iron‐removal experiments and further suggest that addition of DFOB might not impose iron stress uniformly across the biological community.