The specificity of bacterial siderophore receptors probed by bioassays.

The ability to utilize siderophores of bacterial and fungal origin has been studied in wild-type and mutant strains of the enterobacterial genera Salmonella, Escherichia, Shigella, Moellerella, Klebsiella, Enterobacter, Hafnia, Pantoea, Ewingella, Tatumella, Yersinia, and in the non-enterics Aeromonas, Pseudomonas and Aureobacterium. Although only a few representative strains were tested, the results show characteristic genus-specific differences in the utilization of hydroxamate and catecholate siderophores. Moreover, the different response to structural alterations of certain siderophore classes by some wild-type and mutant strains points to variable interacting receptor domains.