title: Delipidation and reactivation of UDPglucuronosyltransferase from rat liver.
abstract: UDPglucuronosyltransferase was solubilized by treating Wistar rat liver microsomes with deoxycholate. Chromatography of this preparation on Bio-Gel P-30 resulted in extraction of 92% of phospholipids and complete loss of enzyme activity. UDPglucuronosyltransferase was reactivated by dialysing this delipidated preparation in the presence of lecithin, a mixture of liver microsomal lipids or microsomal preparations from livers of UDPglucuronosyltransferase-deficient Gunn rats. Virtually complete enzyme reactivation was obtained with regard to glucuronidation and glucosidation of bilirubin; however, the inactivation of UDPglucuronosyltransferase with p-nitrophenol as substrate was irreversible. These findings demonstrate that UDPglucuronosyltransferase with bilirubin as substrate is a lipid-requiring enzyme.
mesh_terms: D000818:Animals; D001663:Bilirubin; D001665:Binding Sites; D002850:Chromatography, Gel; D003840:Deoxycholic Acid; D014453:Glucuronosyltransferase / Q000302:isolation & purification / Q000378:metabolism*; D006602:Hexosyltransferases / Q000378:metabolism*; D007700:Kinetics; D008862:Microsomes, Liver / Q000187:drug effects / Q000201:enzymology*; D009596:Nitrophenols; D010713:Phosphatidylcholines / Q000494:pharmacology; D011485:Protein Binding; D011489:Protein Denaturation; D051381:Rats; D012995:Solubility; D013329:Structure-Activity Relationship; D013696:Temperature; D013997:Time Factors
chemical_list: D009596:Nitrophenols; D010713:Phosphatidylcholines; D003840:Deoxycholic Acid; D006602:Hexosyltransferases; D014453:Glucuronosyltransferase; D001663:Bilirubin