This award in the Chemistry of Life Processes (CLP) program supports work by Professor Michael Maroney at the University of Massachusetts to carry out fundamental studies of the mechanism of superoxide disproportionation catalyzed by nickel-dependent superoxide dismutase, an enzyme found in bacteria. Nickel superoxide dismutases (NiSODs) represent a novel approach to the elimination of superoxide in biological systems, and thus contribute to the biodiversity of mechanisms for oxygen detoxification. Other nickel metalloenzymes play critical roles in microbial redox catalysis, including hydrogen utilization (hydrogenases), methane production (methylcoenzyme M reductase), and CO/CO2 chemistry (carbon monoxide dehydrogenase and acetylcoenzyme A synthase), and are thus important catalysts in energy science.
The study of NiSOD will contribute to our understanding of redox catalysis by biological nickel sites via examination the only redox nickel enzyme characterized to date that contains no other cofactors, and thus offers a clear spectroscopic view of the chemistry involved. These studies, which use a multidisciplinary approach involving molecular biological and spectroscopic techniques, will contribute to our knowledge of the design of redox centers for catalysis that will contribute to synthetic systems for hydrogen production/utilization and CO2 reduction.