Research

Nearly all bacteria require iron to grow.  Many bacteria growing aerobically in iron-starved environments produce siderophores, small MW chelating ligands that coordinate Fe(III) and facilitate iron uptake into the bacterium.  The largest class of new siderophores are acylated, which confer new dynamics in the iron-uptake process. We are investigating the biosynthesis, tailoring, membrane partitioning and biological function of this class of amphiphilic siderophores.

Vanadium haloperoxidases (V-HPO) catalyze the peroxidative halogenation of organic substrates using H2O2 to oxidize the halide (Cl¯, Br¯, or I¯).  We are interested in the activity of these enzymes in the biosynthesis of important halogenated marine natural products, as well as the role of these enzyme in disrupting bacterial quorum sensing on bacteria attempting to colonize the surface of algae.  V-HPOs occur widely in the marine environment, and are especially abundant in algae.

3,4-DOPA (3,4-dihydroxyphenylalanine) and lysine appear to be important components of the mussel foot proteins in the bissel threads which mussels put out to adhere strongly to surfaces in the marine environment.  We are interested in small molecule mimics of this wet adhesion.  We are investigating a class of catechol siderophores and related analogs that adhere strongly to surfaces in aqueous environments. 

Lignin is the World's largest natural source of aromatic carbon. Microbes have evolved to grow on lignin as a carbon source and in the process release discrete aromatic breakout fragments. We are investigating the mechanistic and synergistic aspects of these microbial metalloenzymes.