Graham Palmer

Research Interests:
The discipline of bioenergetics attempts to characterize the biochemical processes whereby the chemical free energy that originates with our diet is made available to living organisms. In eucaryotic systems the relevant processes are catalyzed by enzyme complexes present in the inner membrane of the mitochondrion. These enzymes implement electron transfer reactions, and the passage of electrons through the relevant enzyme complex leads to the translocation of protons across this membrane; the proton gradient so-formed is the primary energy conserving event.

My laboratory is involved in the characterization of two of these enzymes, the ubiquinol cytochrome c oxidoreductase (Complex III) and cytochrome oxidase (Complex IV). The experimental approach depends on the application of spectroscopic and other physical methods, in conjunction with transient state kinetic experiments, to define the structures and dynamics of the species which function in the electron transport, and to a lesser extent, the proton translocation reactions. By these methods many of the stereochemical and electronic properties of the relevant redox active reactants have been defined, and specific kinetic mechanisms have been proposed and examined. o probe this revision. A second area of current concern is the structure and reactivity of the binuclear center comprising cytochrome a3 and CuB and which is the catalytic site for the reduction of oxygen to water. This binuclear center is being studied using a combination of ligand reactivity, electron paramagnetic resonance, resonance Raman and Fourier Transform Infra-Red measurements, and a minimum of three sites for ligand reaction have already been identified. The role of these sites in the catalytic mechanism is being pursued.

A Paris Street Scene by Gustav Caillebot