| Abstract: | Inactivation rate of purified oligomeric cytochrome P-450 LM2 has been investigated in glucose oxidase system and under the action of exogenous hydrogen peroxide (400 microM). It has been found that hydrogen peroxide has a distinct inactivating effect on cytochrome P-450. The enzyme inactivation is accompanied by the loss of heme and the decrease in SH-group content in the protein molecule. Benzphetamine, a substrate specific for this enzyme isoform, exerts a protective effect by decreasing the rate of cytochrome P-450 inactivation and SH-group oxidation. Similar results have been obtained during the investigation of cytochrome P-450 inactivation in the monomerized system. It has been found that the inactivation process is accompanied by the formation of the enzyme aggregates. The changes in the aggregate state are due to the formation of intermolecular covalent bonds. |
