Microbial Iron Acquisition: Investigations of Amphiphilic Siderophores

University Of California-Santa Barbara, Santa Barbara CA

Investigators

Abstract

This award in the Chemistry of Life Processes (CLP) program supports work by Professor Alison Butler at the University of California, Santa Barbara to carry out fundamental studies on the process of iron acquisition by bacteria that is mediated by siderophores. Nearly all bacteria require iron to grow. Siderophores are low molecular mass chelating ligands produced by bacteria that coordinate Fe(III) with very high affinity and facilitate iron uptake by the bacterium. Marine bacteria often produce suites of amphiphilic siderophores that vary in the nature of the fatty acid tail. The interactions of the amphiphilic siderophores, their self-assembled structures and the bacteria will be probed to investigate whether the amphiphilic character of these siderophores confers a distinct molecular advantage for microbial iron acquisition. This project supports the education and training of graduate and undergraduate students in a highly interdisciplinary research project in a manner that will serve to broaden and deepen the level of research training. Some marine bacteria grow on petroleum hydrocarbons as their sole source of carbon and energy; yet before bacteria can begin to oxidize hydrocarbons, they must first acquire iron for growth and then for assimilation into the key enzymes. Thus understanding how oil-degrading bacteria acquire the essential nutrient, iron, would benefit efforts to enhance microbial hydrocarbon oxidation of environmental concern.