A large group of mononuclear non-heme iron enzymes exist which activate dioxygen to catalyze key biochemical transformations, including many of medical, pharmaceutical and environmental significance. These enzymes utilize high-spin Fe^II active sites and additional reducing equivalents from cofactors or substrates to react with O₂ to yield iron-oxygen intermediates competent to transform substrate to product. The a-ketoglutarate (a-KG)-dependent dioxygenases comprise a large and expanding class of mononuclear non-heme iron enzymes which require Fe^II, a-KG and dioxygen for catalysis, with the a-KG cosubstrate supplying the two additional electrons required for dioxygen activation.

My current research projects involve the determination of the geometric and electronic structures of the ferrous active sites of a-KG-dependend enzymes of interest utilizing circular dichroism (CD) and magnetic circular dichroism (MCD) spectroscopies. Current areas of research include HPPD and HmaS, two enzyme which utilize the same substrate but exhibit different reactivities (aromatic electrophilic attack vs. H-atom abstraction). These studies should provide further insight into active site structures and reactivities of the a-KG-dependent dioxygenases.