Rapid release of iron from ferritin by siderophores.

The ability of the microbial siderophores deferriferrichrome, deferriferrichrome A, and enterobactin to remove iron from ferritin has been investigated. In contrast to previously published data with other chelators, all three siderophores rapidly released iron from the mammalian storage protein. Enterobactin was found most efficient at removing ferritin-bound iron. Using this siderophore, the mechanism by which ferritin sequesters iron was studied. The relative iron saturation level of ferritin influenced the rate of chelation by the microbial siderophores.