title: Covalent binding to apoprotein is a major fate of heme in a variety of reactions in which cytochrome P-450 is destroyed.
abstract: The heme in rat liver microsomal cytochrome P-450 was labeled with 14C or 3H and the microsomes were fractionated after in vitro incubations with a variety of agents known to destroy cytochrome P-450 heme. A major fraction of the heme label was irreversibly bound to apoprotein in all cases, including incubations with fluroxene, 1-octene, vinyl bromide, trichloroethylene, vinyl chloride, parathion, cumene hydroperoxide, NaN3, or iron-ADP complex. Label was also extensively bound to apoprotein when purified and reconstituted cytochrome P-450 was incubated with NADPH and vinyl chloride. This process appears to be widespread and involved to a significant extent in the cytochrome P-450 heme destruction observed with many compounds.
mesh_terms: D000475:Alkenes / Q000494:pharmacology; D000818:Animals; D001386:Azides / Q000494:pharmacology; D001555:Benzene Derivatives / Q000494:pharmacology; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D004987:Ethers / Q000494:pharmacology; D006418:Heme / Q000378:metabolism*; D008862:Microsomes, Liver / Q000201:enzymology; D010278:Parathion / Q000494:pharmacology; D051381:Rats; D019810:Sodium Azide; D014241:Trichloroethylene / Q000494:pharmacology; D014752:Vinyl Chloride / Q000494:pharmacology; D014753:Vinyl Compounds / Q000494:pharmacology
chemical_list: D000475:Alkenes; D001386:Azides; D001555:Benzene Derivatives; D004987:Ethers; D014753:Vinyl Compounds; D014241:Trichloroethylene; D006418:Heme; D010278:Parathion; C003763:vinyl bromide; D003577:Cytochrome P-450 Enzyme System; D019810:Sodium Azide; C037690:1-octene; C007164:cumene hydroperoxide; D014752:Vinyl Chloride