Abstract
Hydroxamate siderophores (HSs), in the form of desferrioxamine B, desferrichrome A, and an unknown mixture derived from Boletus edulis, formed stable iron (Fe) chelates in both acid and alkaline soils as determined by chelation modeling and laboratory experiments. Desferrioxamine B and the unknown mixture were more strongly adsorbed to soil than desferrichrome A. Data obtained using similar methodology indicated that citrate, oxalate, α-ketoglutarate, malate, malonate, succinate, and pyruvate did not chelate Fe effectively at alkaline soil pH, and only citrate was a reasonably effective Fe-chelating agent at acid soil pH. These data, coupled with previous work demonstrating biologically significant levels of HS in soils, indicate that HS can function as Fe mobilizers in ecosystems. Hydroxamate siderophores (HSs), in the form of desferrioxamine B, desferrichrome A, and an unknown mixture derived from Boletus edulis, formed stable iron (Fe) chelates in both acid and alkaline soils as determined by chelation modeling and laboratory experiments. Desferrioxamine B and the unknown mixture were more strongly adsorbed to soil than desferrichrome A. Data obtained using similar methodology indicated that citrate, oxalate, α-ketoglutarate, malate, malonate, succinate, and pyruvate did not chelate Fe effectively at alkaline soil pH, and only citrate was a reasonably effective Fe-chelating agent at acid soil pH. These data, coupled with previous work demonstrating biologically significant levels of HS in soils, indicate that HS can function as Fe mobilizers in ecosystems. © Williams & Wilkins 1983. All Rights Reserved.