Dr. Whitman's laboratory is interested in how enzymes evolve and how they work. We are studying two groups of enzymes, the tautomerase superfamily and the fumaryl acetoacetate hydrolase (FAH) superfamily. Both superfamilies likely evolved from common ancestors through divergent evolution. The members of the tautomerase superfamily use a conserved amino-terminal proline and an arginine to catalyze diverse reactions including tautomerization, dehalogenation, hydration, and decarboxylation. The FAH superfamily members use an enzyme-bound metal ion to catalyze hydrolysis, decarboxylation, and perhaps hydration reactions.