title: S-oxygenation of an alkylmercaptotriazine herbicide by rat, rabbit and human liver enzymes.
abstract: 1. The oxidation of the herbicide cyanatryn to cyanatryn S-oxide and de-ethylcyanatryn was used to study S-oxidation and N-de-ethylation in liver microsomes from three species. 2. Both reactions were dependent upon NADPH and were inhibited by methyrapone and CO. However, the enzyme catalysing N-de-ethylation exhibited different species/sex specificity from the S-oxygenase. 3. Rat liver flavoprotein S-oxygenase had no action on cyanatryn, suggesting, with the other data, that the S-oxygenation was catalysed by cytochrome P-450. 4. S-Oxygenation proceeded rapidly in human liver microsomes and the rats was linear for 60 min at 37 degrees C.
mesh_terms: D000818:Animals; D001711:Biotransformation; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D005260:Female; D006540:Herbicides / Q000378:metabolism*; D006801:Humans; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology / Q000378:metabolism*; D009249:NADP / Q000378:metabolism; D000587:Oxidoreductases Acting on CH-NH Group Donors / Q000378:metabolism; D011817:Rabbits; D051381:Rats; D014227:Triazines / Q000378:metabolism*
chemical_list: D006540:Herbicides; D014227:Triazines; D009249:NADP; D003577:Cytochrome P-450 Enzyme System; D000587:Oxidoreductases Acting on CH-NH Group Donors; C010435:cyanatryn