Promiscuous Pseudomonas: Uptake of Non-Endogenous Ligands for Iron Acquisition

Iron is an essential nutrient to nearly all living beings. However, its acquisition poses a significant challenge to many organisms, including most bacteria. One of the main iron uptake strategies employed by bacteria is the uptake of siderophores, small molecules that chelate extracellular iron. The pathogenic species Pseudomonas aeruginosa produces two different siderophores, pyochelin and pyoverdine. P. aeruginosa senses the amount of bioavailable extracellular iron in order to regulate the production levels of each of these two siderophores. In previous work, we found that a series of pyochelin biosynthetic shunt products enhanced the growth of P. aeruginosa in iron-depleted conditions when prechelated with iron. Thus, on the basis of these results, we investigated the physiochemical and biological properties of a series of non-native oxygen counterparts to these metabolites in the current study.