Active site coordination chemistry of the cytochrome c peroxidase Asp235Ala variant: spectroscopic and functional characterization

H NMR spectroscopic studies on the electronic and functional properties of Asp235 in yeast cytochrome c peroxidase reveal that the spin state and coordination characteristics of the heme iron in cytochrome C peroxidase do not control the substrate oxidation rate. The iron segment influences the pH-based properties of the active site of Asp235Ala variant. Asp235 is vital for the catalytic activity of the enzyme as it regulates exact Trp 191 orientation for electron exchange within cytochrome c peroxidase - cytochrome C complex.