Studies on the hemeproteins, hemoglobin, myoglobin, catalase, peroxidase and cytochrome P-450 will be carried out in order to determine the mechanisms of action of oxygen storage, transport and activation and the mechanisms of electron transport. These enzymes and simple metalloporphyrins will be studied using electrochemical, kinetic, optical and magnetic resonance techniques. The goals are an understanding of the structural and electronic effects which govern the proper functioning of these proteins, as well as the causes and effects of their misfunctioning such as with abnormal hemoglobins and heptatic destruction of P-450 by unsaturated xenobiotics.