Browse
Submit Data
Databases
API
Help

Dataset Information

8 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Immunochemical comparison of UDP-glucuronyltransferase from Gunn- and Wistar-rat livers.

ABSTRACT: 1. Antiserum was raised against purified Wistar-rat liver UDP-glucuronyltransferase. 2. UDP-glucuronyltransferase activities towards 4-nitrophenol, bilirubin, 1-naphthol and morphine were co-immunoprecipitated from solubilized Wistar-rat liver preparations. 3. UDP-glucuronyltransferase activities towards 1-naphthol, 2-aminophenol and 4-nitrophenol were precipitated from solubilized Gunn-rat liver preparations by this antiserum. 4. UDP-glucuronyltransferase activities towards 1-naphthol, 4-nitrophenol and bilirubin, from Wistar-rat liver, were slightly inhibited by antiserum, whereas 1-naphthol UDP-glucuronyltransferase activity from Gunn-rat livers was greatly inhibited. 5. Measurable Wistar-rat liver glucuronyltransferase activities in washed immunoprecipitates indicate that the enzyme(s) were not merely inhibited by antiserum. 6. Immunoglobulin G purified from this antiserum immunoprecipitated transferase activities towards 4-nitrophenol, bilirubin and 1-naphthol. 7. The washed immunoprecipitates from both rat strains, containing UDP-glucuronyltransferase activity, appear to be similar when analysed by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. 8. Radial-immunodiffusion studies suggest that a smaller amount of UDP-glucuronyltransferase protein is present in Gunn-rat liver than in Wistar-rat liver. 9. The significance of these results in relation to the genetic deficiency in the Gunn rat is discussed.

SUBMITTER: Weatherill PJ

PROVIDER: S-EPMC1162193 | biostudies-other | 1980 Oct

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Similar Datasets

Reconstitution of purified Wistar rat liver bilirubin UDP-glucuronyltransferase into Gunn-rat liver microsomes.

Project description:1. Reconstitution of purified bilirubin UDP-glucuronyltransferase from Wistar-rat liver into Gunn-rat liver microsomes provides a better environment than phosphatidylcholine liposomes, such that the final specific activity of the Wistar-rat liver enzyme was increased up to 85 units/mg of protein. 2. Gunn- and Wistar-rat liver microsomes were equally effective for reconstitution of the purified enzyme. 3. The transferase activity does not appear to be fully expressed in the more rigid environment of foetal Wistar-rat liver microsomes. 4. These reconstitution experiments reveal a final specific activity for the purified bilirubin UDP-glucuronyltransferase consistent with the capacity of the whole rat liver to glucuronidate bilirubin and indicate that the absence of this enzyme activity in Gunn-rat liver microsomes is not due to an abnormal microenvironment.

| S-EPMC1163694 | biostudies-other

Separation of oestrone UDP-glucuronyltransferase and p-nitrophenol UDP-glucuronyltransferase activities.

Project description:Rabbit liver UDP-glucuronyltransferase activity was resolved into two separate fractions on DEAE-cellulose, one containing most of the transferase activity toward oestrone and the other most of the activity toward p-nitrophenol. These two activities were completely separated by rechromatography of each fraction on a second DEAE-cellulose column.

| S-EPMC1184011 | biostudies-other

Phospholipid-dependence of oestrone UDP-glucuronyltransferase and p-nitrophenol UDP-glucuronyltransferase.

Project description:Hepatic UDP-glucuronyltransferase activity was resolved into two fractions, one exhibiting oestrone glucuronyltransferase activity and the other exhibiting p-nitrophenol glucuronyltransferase activity. Hydroxyapatite-column chromatography removed greater than 95% of the phospholipids from both preparations. The partially purified delipidated enzymes were essentially devoid of catalytic activity, but activities were restored by the addition of phospholipids or phosphatidylcholine mixtures containing various saturated and unsaturated fatty acids. Both oestrone and p-nitrophenol glucuronyl-transferase activities were reconstituted to similar degrees with the phosphatidylcholine mixtures. When purified phospholipids were tested, phosphatidylcholine and lysophosphatidylcholine were most effective in restoring activity, whereas phosphatidylethanolamine was the least effective. These results further suggest that oestrone and p-nitrophenol UDP-glucuronyltransferases are dependent on phospholipids for their activity.

| S-EPMC1186595 | biostudies-other

Bilirubin glucuronidation by intact Gunn rat fibroblasts expressing bilirubin UDP-glucuronosyltransferase.

Project description:Crigler-Najjar (CN) disease is an inherited disorder of bilirubin metabolism. The disease is caused by a deficiency of the hepatic enzyme bilirubin UDP-glucuronosyltransferase (B-UGT). Patients with CN disease have high serum levels of the toxic compound, unconjugated bilirubin. The only defect in bilirubin metabolism of CN patients is the absence of B-UGT activity. The transplantation of cells able to glucuronidate bilirubin should therefore lower serum bilirubin levels. The Gunn rat is the animal model of CN disease. Primary Gunn rat fibroblasts (GURF) were transduced with a recombinant retrovirus, capable of transferring B-UGT cDNA. A cell line was obtained expressing B-UGT at a level comparable to hepatocytes. Bilirubin added to the culture medium of these cells was glucuronidated and excreted. The B-UGT activities of transduced GURF and freshly isolated Wistar hepatocytes were compared at different bilirubin concentrations. The specific B-UGT activities of these two cell types were comparable when physiological bilirubin concentrations (5-10 microM) were present in the culture media. At higher bilirubin concentrations (20-80 microM) the hepatocytes were more active than the transduced GURF. We conclude that with the addition of only one enzyme (B-UGT) fibroblasts can perform the complete set of reactions necessary for bilirubin glucuronidation. The difference in B-UGT activity between transduced GURF and hepatocytes at 20-80 microM bilirubin can be explained by lower UDP-glucuronic acid and glutathione S-transferase levels in GURF. Our findings also indicate that these cells could be used to develop extrahepatic gene therapy for CN disease.

| S-EPMC1217075 | biostudies-other

Strain differences in rat liver (UDP-glucuronyltransferase activity towards androsterone.

Project description:Male Donryu, Wistar King rats showed discontinuous variations in hepatic microsomal UDP-glucuronyltransferase activities towards androsterone, but not towards testosterone, bilirubin, phenolphthalein and 4-nitrophenol. Fresh microsomal fraction with a low transferase activity towards androsterone formed 0.049--0.080 nmole of glucuronide/min per mg of protein, whereas fresh microsomal fraction with a high transferase activity towards androsterone formed 0.335--0.557 nmol of glucuronide/min per mg of protein. The microsomal fraction with low enzyme activity towards androsterone was not stimulated by treatment with Triton X-100 or freezing and thawing. In contrast, male Long Evans and Sprague-Dawley rats did not exhibit such diversity.

| S-EPMC1186654 | biostudies-other

Stimulation of defective Gunn-rat liver uridine diphosphate glucuronyltransferase activity in vitro by alkyl ketones.

Project description:Addition of alkyl ketone (10mM) to Gunn-rat liver homogenates increased UDP-glucuronyltransferase activity towards 2-aminophenol by 10--20 fold, up to enhanced values of enzyme activity observed with similarly treated Wistar-rat liver homogenates. Alkyl ketones also activate the defective enzyme purified from Gunn-rat liver. This genetic deficiency of UDP-glucuronyltransferase activity is no longer apparent when assayed in the presence of alkyl ketones.

| S-EPMC1186469 | biostudies-other

Comparison of the biliary excretion of the four isomers of bilirubin-IX in Wistar and homozygous Gunn rats.

Project description:The biliary excretion of the four isomers of bilirubin-IX was studied in Wistar rats (JJ) and homozygous Gunn rats (jj). Synthetic preparations of 14C-labelled pigments were used. 1. After intravenous administration, the alpha-isomer was rapidly excreted in conjugated form in bile of Wistar rats. In Gunn rats excretion was insignificant. In contrast, both rat species promptly excreted the non-alpha-isomers at rates that were comparable with that found for bilirubin-IXalpha in Wistar rats. 2. In normal rats about 16% of the beta- and delta-isomers and at least 50% of the gamma-isomer were excreted as ester conjugates of the injected parent bile pigments. Conjugation of the beta- and delta-isomers had occurred exclusively at the carboxyl groups of pyrrole ring D and C respectively. For bilirubin-IXgamma no preference for any carboxyl group could be established. 3. In homozygous Gunn rats the non-alpha-isomers were apparently excreted chemically unaltered. This suggests that, as for bilirubin-IXalpha, conjugation of the non-alpha-isomers is also deficient in Gunn rats.

| S-EPMC1164778 | biostudies-other

Perinatal developmental changes in hepatic UDP-glucuronyltransferase.

Project description:Postnatal developmental changes in hapatic microsomal UDP-glucuronyltransferase were studied in the rat. The previously reported postnatal decline in the capacity of microsomal fractions to glucuronidate p-nitrophenol was found to be observable in unperturbed preparations only at non-saturating concentrations of the substrate UDP-glucuronic acid. At saturating concentrations of UDP-glucuronic acid, activity is identical in newborns and adults. Kinetic analysis revealed that the enzyme from liver of newborns has a much higher affinity for UDP-glucuronic acid than does the enzyme in adults, but the same activity at Vmax. On the other hand, the enzyme from adult liver microsomal fractions can be activated by the physiological allosteric effector UDP-N-acetylglucosamine, whereas the enzyme from newborns is largely unaffected by it. Thus it appears that the number of enzyme active sites is not changing; rather, the enzyme is maturing to a more highly regulable form. There were also differences between the enzymes in newborns and adults in their response to perturbation of the membrane-lipid environment by detergent and phospholipase A. Possible interpretations of these differences are discussed.

| S-EPMC1161721 | biostudies-other

The separation and purification of rat liver UDP-glucuronyltransferase activities towards testosterone and oestrone.

Project description:1. Reconstitution of UDP-glucuronyltransferase preparations with phosphataidylcholine liposomes facilitated the purification of testosterone UDP-glucuronyltransferase. 2. Transferase activity towards testosterone co-purifies with that towards 4-nitrophenol. 3. UDP-glucuronyltransferase activity towards oestrone was separated from that towards testosterone. 4. These results suggest that testosterone and 4-nitrophenol may be glucuronidated by a different form of UDP-glucuronyltransferase from the one glucuronidating oestrone.

| S-EPMC1162010 | biostudies-other

Bilirubin mono- and di-glucuronide formation by purified rat liver microsomal bilirubin UDP-glucuronyltransferase.

Project description:Highly purified bilirubin UDP-glucuronyltransferase from Wistar-rat liver, when reconstituted with Gunn-rat liver microsomes (microsomal fraction), was able to catalyse the conversion of unesterified bilirubin into both bilirubin monoglucuronide and diglucuronide. Under zero-order kinetic conditions for monoglucuronide formation, the fraction of bilirubin diglucuronide formed by incubation of bilirubin with the reconstituted highly purified transferase accounted for 18% of total bilirubin glucuronides, which was only slightly lower than the fraction of diglucuronides (23% of total bilirubin glucuronides) formed by incubation with hepatic microsomes in the presence of UDP-N-acetylglucosamine or Lubrol. The reconstituted purified enzyme also catalysed the UDP-glucuronic acid-dependent conversion of bilirubin monoglucuronide into diglucuronide and, when bilirubin was incubated with UDP-glucose or UDP-xylose, the formation of bilirubin glucosides and xylosides respectively. These results suggest that a single microsomal bilirubin UDP-glycosyltransferase may be responsible for the formation of bilirubin mono- and di-glycosides.

| S-EPMC1144319 | biostudies-other

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data