Active metabolites in toxicology: the role of cytochrome P-448 and flavoprotein oxidases.
The activation of toxic chemicals and carcinogens into reactive intermediates involves oxygenation in hindered positions of the molecule, by cytochrome P-448 (LM4), flavoprotein oxidoreductases, or transoxygenation during prostaglandin biosynthesis. Cytochrome P-450 (LM2) does not oxygenate in hindered positions and therefore generally detoxicates carcinogens and toxic chemicals. Cytochrome P-448 has a different active site from cytochrome P-450, which enables it to oxygenate substrates in conformationally-hindered positions.
D000818:Animals; D001711:Biotransformation; D002273:Carcinogens / Q000378:metabolism; D019388:Cytochrome P-450 CYP1A2; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D003580:Cytochromes / Q000378:metabolism*; D005420:Flavoproteins / Q000378:metabolism; D066298:In Vitro Techniques; D008099:Liver / Q000378:metabolism; D008297:Male; D006899:Mixed Function Oxygenases / Q000378:metabolism; D004364:Pharmaceutical Preparations / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
D002273:Carcinogens; D003580:Cytochromes; D005420:Flavoproteins; D004364:Pharmaceutical Preparations; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; C017170:Cyp1a2 protein, rat; D019388:Cytochrome P-450 CYP1A2