title: Kinetics of elementary steps in the cytochrome P-450 reaction sequence. V. Laser temperature-jump investigation of the spin relaxation kinetics of cytochrome P-450 LM2.
abstract: The cytochrome P-450 LM2 spin state relaxation kinetics has been resolved by means of laser temperature-jump techniques. The first order rate constants amount to about 10(6) S-1 in the substrate-free and the substrate-bound protein, respectively. Evidence is provided that the spin equilibrium preequilibrates the P-450 reduction but is not rate-limiting. Additional capacitor discharge temperature-jump studies elucidate substrate dependent perturbations.
mesh_terms: D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D007527:Isoenzymes / Q000378:metabolism*; D007700:Kinetics; D007834:Lasers; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism*; D011485:Protein Binding; D011487:Protein Conformation; D011817:Rabbits; D013696:Temperature
chemical_list: D007527:Isoenzymes; D003577:Cytochrome P-450 Enzyme System