title: Covalent binding to protein of the K-region oxide of benzo(a)pyrene formed by microsome incubation.
abstract: Incubation of 20,000 X g supernatant proteins of rat liver with benzo]a]pyrene (BP) and appropriate cofactors produced metabolites of BP covalently bound at the 4,5- position to protein. After being incubated, protein samples were freed from noncovalently bound metabolites and hydrolyzed chemically or both enzymatically and chemically. All steps were performed under minimum exposure to light and air; benzene extracts were prepared during hydrolysis. Chemical hydrolysis released the K-region metabolite BP-4,5-dihydrodiol (identified by UV and mass spectra) and BP. Hydrolysis with trypsin and pronase gave products with the characteristic UV spectrum of substituted chrysene. Chemical hydrolysis of these products released BP and BP-4,5-dihydrodiol.
mesh_terms: D000818:Animals; D001580:Benzopyrenes / Q000378:metabolism*; D001665:Binding Sites; D055598:Chemical Phenomena; D002621:Chemistry; D006868:Hydrolysis; D066298:In Vitro Techniques; D007700:Kinetics; D008862:Microsomes, Liver / Q000378:metabolism; D011506:Proteins / Q000302:isolation & purification / Q000378:metabolism*; D051381:Rats
chemical_list: D001580:Benzopyrenes; D011506:Proteins