OXIDATIVE MODIFICATION OF CYTOCHROME-P-450 DURING ITS OPERATION .2. INVESTIGATION OF THE MECHANISM OF INACTIVATION OF CYTOCHROME-P-450 LM2 IN A SOLUBLE RECONSTITUTED MONOOXYGENASE SYSTEM

The inactivation of cytochrome P-450 LM2 under the action of hydrogen peroxide, formed in the active site of the enzyme, was investigated. It was found that catalase does not protect the hemoprotein from inactivation during its work in a soluble reconstituted system. The inactivation of cytochrome P-450 LM2 in this system depends on the ratio of the hemo- and flavoproteins. The inactivation of cytochrome P-450 LM2 during catalysis was found to be accompanied by cleavage of the hemoprotein molecule, which may be the deciding factor in the regulation of the breakdown of the enzyme.