Our research is focused on understanding how metalloenzymes operate. We are interested in defining the mechanism and reactive intermediates used by oxidative heme enzymes such as cytochrome P450, nitric oxide synthase and peroxidases. These enzymes utilize O2 to generate highly reactive intermediates containing hypervalent iron and radical species (Fe+4=O, R+.) to catalyze the hydroxylation of a huge variety of substrates. Understanding how nature controls and directs this reactivity is one of the main focuses of our work. Our laboratory is trying to determine how substrates are recognized by a particular P450 and how the structural changes are coupled to function. We are also working to re-engineer and evolve these enzymes to develop catalysts capable of oxidizing novel substrates. Our experimental approach involves the integrated use of multidisciplinary techniques including molecular biology, protein engineering, x-ray crystallography, electron paramagnetic resonance, electrochemistry, calorimetry and kinetics. Engineered enzymes may have practical utility as bio-sensors, reagents for stereospecific chemical transformations and bio-remediation. More generally, our research may contribute to the understanding of metalloenzyme function, protein-ligand interactions, molecular recognition and drug design
