Interaction between cytochrome P450 and other drug-metabolizing enzymes: evidence for an association of CYP1A1 with microsomal epoxide hydrolase and UDP-glucuronosyltransferase.
Protein-protein interactions between cytochrome P450 (P450) and other drug-metabolizing enzymes were studied by affinity chromatography using CYP1A1-, glycine-, and bovine serum albumin (BSA)-conjugated Sepharose 4B columns. Sodium cholate-solubilized microsomes from phenobarbital-treated rat liver were applied to the columns and the material eluted with buffer containing NaCl was analyzed by immunoblotting. Microsomal epoxide hydrolase (mEH) and UDP-glucuronosyltransferases (UGTs), as well as NADPH-P450 reductase, were efficiently trapped by the CYP1A1 column. Glycine and BSA columns exhibited no ability to retain these proteins. Protein disulfide isomerase and calnexin, non-drug-metabolizing enzymes expressed in the endoplasmic reticulum, were unable to associate with the CYP1A1 column. These results suggest that CYP1A1 interacts with mEH and UGT to facilitate a series of multistep drug metabolic conversions.
Taura
K I
KI
Graduate School of Pharmaceutical Sciences, School of Health Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
Yamada
H
H
Hagino
Y
Y
Ishii
Y
Y
Mori
M A
MA
Oguri
K
K
D000818:Animals; D015153:Blotting, Western; D002417:Cattle; D002846:Chromatography, Affinity; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism*; D004851:Epoxide Hydrolases / Q000378:metabolism*; D014453:Glucuronosyltransferase / Q000378:metabolism*; D008297:Male; D011485:Protein Binding; D051381:Rats; D017207:Rats, Sprague-Dawley
D019363:Cytochrome P-450 CYP1A1; D014453:Glucuronosyltransferase; D004851:Epoxide Hydrolases