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Title: Isolation and purification of rat liver morphine UDP-glucuronosyltransferase

The enhancement of rat liver microsomal morphine (M) and 4-hydroxybiphenyl (4-HBP) UDP-glucuronyltransferase (UDPGT) activities by phenobarbital treatment has been proposed to represent increased activity of a single enzyme form, GT-2. They have separated M and 4-HBP UDPGT activities from Emulgen 911-solubilized microsomes obtained from livers of phenobarbital-treated Wistar rats. A sensitive assay procedure was developed to quantify M-UDPGT and 4-HBP-UDPGT activities using /sup 14/C-UDP-glucuronic acid (UDPGA) and reversed phase C-18 minicolumns whereby the radioactive glucuronides were differentially eluted from labeled UDPGA. Trisacryl DEAE, and chromatofocusing procedures were employed to separate M-UDPGT and 4-HBP-UDPGT in the presence of exogenous phosphatidylcholine (PC). The PC is necessary to stabilize UDPGT activities. M-UDPGT was isolated to apparent homogeneity and displayed a monomeric molecular weight of 56,000 daltons on SDS-PAGE. It reacted with M but not with 4-HBP, bilirubin, p-nitrophenol, testosterone, androsterone, estrone, 4-aminobiphenyl or ..cap alpha..-naphthylamine. 4-HBP-UDPGT did not react with M. Therefore, M and 4-HBP glucuronidations are catalyzed by separate enzymes in rat liver microsomes.
Authors:
;
Publication Date:
OSTI Identifier:
6763895
Report Number(s):
CONF-8604222-
Journal ID: CODEN: FEPRA; TRN: 87-010339
Resource Type:
Conference
Resource Relation:
Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States); Journal Volume: 45:4; Conference: 70. annual meeting of the Federation of American Society for Experimental Biology, St. Louis, MO, USA, 13 Apr 1986
Research Org:
Univ. of Iowa, Iowa City
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; TRANSFERASES; ENZYME ACTIVITY; PURIFICATION; BIOASSAY; CARBON 14 COMPOUNDS; GLUCURONIC ACID; LIVER; MICROSOMES; MOLECULAR WEIGHT; MORPHINE; PHOSPHOLIPIDS; RATS; TRACER TECHNIQUES; ALDEHYDES; ALKALOIDS; ANALGESICS; ANIMALS; BODY; CARBOXYLIC ACIDS; CELL CONSTITUENTS; CENTRAL NERVOUS SYSTEM DEPRESSANTS; DIGESTIVE SYSTEM; DRUGS; ENZYMES; ESTERS; GLANDS; HYDROXY ACIDS; ISOTOPE APPLICATIONS; LABELLED COMPOUNDS; LIPIDS; MAMMALS; NARCOTICS; OPIUM; ORGANIC ACIDS; ORGANIC COMPOUNDS; ORGANIC PHOSPHORUS COMPOUNDS; ORGANOIDS; ORGANS; RODENTS; VERTEBRATES 550201* -- Biochemistry-- Tracer Techniques