Tolbutamide hydroxylase

Jones, B. C., Hawksworth, G., Home, V. A., et al. (1996) Putative active site template model for cytochrome P4502C9 (tolbutamide hydroxylase). Drug Metab. Dispos. 24, 260-266. 

Jones BC, Hawksworth G, Home VA, et al. Putative active site model for CYP2C9 (tolbutamide hydroxylase). Drag Metab Dispos 1996 24 1-7. 

The three-in-one assay is conducted using pools of human liver microsomes from 10 to 20 donors. The microsomes are frozen in small aliquots and stored at -80°C until use. In this assay, hydroxytolbutamide, dextrorphan, and 6-p-hydroxytcstos-terone that are formed from tolbutamide hydroxylase (CYP 2C9 reaction) [53], dextromethorphan 0-demethylase (CYP 2D6 reaction) [53,54], and testosterone 6-P-hydroxylase (CYP 3A4 reaction) [55], respectively, are quantified by LC-MS/ MS in an approximately 1 min run time. 

R.S. Lloyd, and F.P. Guengerich (1989). Expression of a human liver cytochrome P-450 protein with tolbutamide hydroxylase activity in Saccharomyces cerevisiae. Biochemistry 28, 4993-4999. 

Ohgiya, S., M. Komori, H. Ohi, K. Shiramatsu, N. Shinriki, and T. Kamataki (1992). Six-base deletion occurring in messages of human cytochrome P-450 in the CYP2C subfamily results in reduction of tolbutamide hydroxylase activity. Biochem. Int. 27, 1073-1081. 

Back DJ, Tjia JF, Karbwang J and Colbert J (1988) In vitro inhibition studies of tolbutamide hydroxylase activity of human liver microsomes by azoles, sulphona-mides and quinolines. British Journal of Clinical Pharmacology 26 23-29. 

Srivastava PK, Yun CH, Beaune PH, Ged C, Gueng-erich FP (1991) Separation of human liver microsomal tolbutamide hydroxylase and (5)-mephe-nytoin 4 -hydroxylase cytochrome P-450 enzymes. Mol Pharmacol 40 69-79... 

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