scholarly journals Cholic acid binding by glutathione S-transferases from rat liver cytosol

1980 ◽  
Vol 185 (1) ◽  
pp. 83-87 ◽  
Author(s):  
J D Hayes ◽  
R C Strange ◽  
I W Percy-Robb
Keyword(s):  
Bile Acid ◽  
Cholic Acid ◽  
Reduced Glutathione ◽  
Binding Activity ◽  
Transferase Activity ◽  
Glutathione S Transferase ◽  
Liver Cytosol ◽  
Glutathione S Transferases ◽  
Rat Livers ◽  
Rat Liver Cytosol

Cholic acid-binding activity in cytosol from rat livers appears to be mainly associated with enzymes having glutathione S-transferase activity; at least four of the enzymes in this group can bind the bile acid. Examination of the subunit compositions of different glutathione S-transferases indicated that cholic acid binding and the ability to conjugate reduced glutathione with 1,2-dichloro-4-nitrobenzene may be ascribed to different subunits.

scholarly journals A study of the structures of the YaYa and YaYc glutathione S-transferases from rat liver cytosol Evidence that the Ya monomer is responsible for lithocholate-binding activity

1981 ◽  
Vol 197 (2) ◽  
pp. 491-502 ◽  
Author(s):  
J D Hayes ◽  
R C Strange ◽  
I W Percy-Robb
Keyword(s):  
Rat Liver ◽  
Lithocholic Acid ◽  
Binding Activity ◽  
Glutathione S Transferase ◽  
Liver Cytosol ◽  
Molecular Weights ◽  
Tryptic Digest ◽  
Glutathione S Transferases ◽  
Limited Digestion ◽  
Rat Liver Cytosol

The two dimeric lithocholic acid-binding proteins previously identified as ligandin (YaYa) and glutathione S-transferase B (YaYc) were isolated from rat liver cytosol. These proteins have molecular weights of 44000 and 47000 respectively. The recovery of these two proteins from liver was not affected by the addition of the proteinase inhibitor Trasylol. No spontaneous interconversion between these two proteins was observed on storage. YaYa and YaYc proteins yielded peptides of identical molecular weight after limited digestion with Staphylococcus aureus V8 proteinase. Analytical and preparative tryptic-digest peptide ‘maps’ showed that all the soluble peptides obtained from YaYa protein were also recovered from YaYc protein. Approximately six extra soluble peptides, which were not recovered from YaYa protein, were obtained from the tryptic digest of YaYc protein. Subdigests of the insoluble tryptic-digest ‘cores’ also resulted in the recovery of identical peptides from both proteins. Evidence is presented that the Ya subunit possessed by both proteins is identical; glutathione S transferase B is a hybrid of ligandin and glutathione S-transferase AA. The Ya monomer is responsible for lithocholate binding.

scholarly journals Identification of two lithocholic acid-binding proteins. Separation of ligandin from glutathione S-transferase B

1979 ◽  
Vol 181 (3) ◽  
pp. 699-708 ◽  
Author(s):  
J D Hayes ◽  
R C Strange ◽  
I W Percy-Robb
Keyword(s):  
Enzyme Activity ◽  
Binding Proteins ◽  
Peptide Mapping ◽  
Lithocholic Acid ◽  
Transferase Activity ◽  
Glutathione S Transferase ◽  
Liver Cytosol ◽  
Structural Differences ◽  
Distinct Subunit ◽  
Rat Liver Cytosol

1. Two lithocholic acid-binding proteins in rat liver cytosol, previously shown to have glutathione S-transferase activity, were resolved by CM-Sephadex chromatography. 2. Phenobarbitone administration resulted in induction of both binding proteins. 3. The two proteins had distinct subunit compositions indicating that they are dimers with mol.wts. 44 000 and 47 000. 4. The two lithocholic acid-binding proteins were identified by comparing their elution volumes from CM-Sephadex with those of purified ligandin and glutathione S-transferase B prepared by published procedures. Ligandin and glutathione S-transferase B were eluted separately, as single peaks of enzyme activity, at volumes equivalent to the two lithocholic acid-binding proteins. 5. Peptide ‘mapping’ revealed structural differences between the two proteins.

scholarly journals BENZYLIDENE CYCLOPENTANONE DERIVATIVES AS INHIBITORS OF RAT LIVER GLUTATHIONE S-TRANSFERASE ACTIVITIES

2010 ◽  
Vol 5 (1) ◽  
pp. 71-75 ◽  
Author(s):  
Sudibyo Martono
Keyword(s):  
Rat Liver ◽  
Potent Inhibitor ◽  
Inflammatory Activity ◽  
Glutathione S Transferase ◽  
Inhibitory Potency ◽  
Liver Cytosol ◽  
Curcumin Analogues ◽  
Glutathione S Transferases ◽  
Anti Inflammatory ◽  
Rat Liver Cytosol

The effect of the curcumin analogues, 2,6-bis-(4-hydroxy-3-methoxy benzylidene) cyclopentanone (B1) and two of its derivatives on m class glutathione S-transferases (GSTs) from phenobarbital-induced and uninduced rat liver cytosol has been studied to elucidate their anti-inflammatory activity. GST activity was monitored spectrophotometrically using 1,2-dichloro-4-nitrobenzene. B1 was the most potent inhibitor of GSTs, both in uninduced and in phenobarbital-induced rat liver cytosol. These inhibitory properties might be explained as part of the anti-inflammatory activity of benzylidene cyclopentanone derivatives (B1 and B12).   Keywords: curcumin; benzylidene cyclopentanone; inhibitory potency; glutathione S-transferases mesoporous

scholarly journals Isoelectric focusing of glutathione S-transferases from rat liver and kidney

1978 ◽  
Vol 175 (3) ◽  
pp. 937-943 ◽  
Author(s):  
Barbara F. Hales ◽  
Valerie Jaeger ◽  
Allen H. Neims
Keyword(s):  
Substrate Specificity ◽  
Isoelectric Focusing ◽  
Transferase Activity ◽  
Sprague Dawley ◽  
Substrate Specificities ◽  
Liver Cytosol ◽  
Sprague Dawley Rats ◽  
Isoelectric Points ◽  
Liver And Kidney ◽  
Glutathione S Transferases

The glutathione S-transferases that were purified to homogeneity from liver cytosol have overlapping but distinct substrate specificities and different isoelectric points. This report explores the possibility of using preparative electrofocusing to compare the composition of the transferases in liver and kidney cytosol. Hepatic cytosol from adult male Sprague–Dawley rats was resolved by isoelectric focusing on Sephadex columns into five peaks of transferase activity, each with characteristic substrate specificity. The first four peaks of transferase activity (in order of decreasing basicity) are identified as transferases AA, B, A and C respectively, on the basis of substrate specificity, but the fifth peak (pI6.6) does not correspond to a previously described transferase. Isoelectric focusing of renal cytosol resolves only three major peaks of transferase activity, each with narrow substrate specificity. In the kidney, peak 1 (pI9.0) has most of the activity toward 1-chloro-2,4-dinitrobenzene, peak 2 (pI8.5) toward p-nitrobenzyl chloride, and peak 3 (pI7.0) toward trans-4-phenylbut-3-en-2-one. Renal transferase peak 1 (pI9.0) appears to correspond to transferase B on the basis of pI, substrate specificity and antigenicity. Kidney transferase peaks 2 (pI8.5) and 3 (pI7.0) do not correspond to previously described glutathione S-transferases, although kidney transferase peak 3 is similar to the transferase peak 5 from focused hepatic cytosol. Transferases A and C were not found in kidney cytosol, and transferase AA was detected in only one out of six replicates. Thus it is important to recognize the contribution of individual transferases to total transferase activity in that each transferase may be regulated independently.

scholarly journals The presence and longitudinal distribution of the glutathione S-transferase in rat epididymis and vas deferens

1980 ◽  
Vol 189 (1) ◽  
pp. 135-142 ◽  
Author(s):  
Barbara F. Hales ◽  
Christiane Hachey ◽  
Bernard Robaire
Keyword(s):  
Substrate Specificity ◽  
Isoelectric Focusing ◽  
Vas Deferens ◽  
Longitudinal Distribution ◽  
Transferase Activity ◽  
Glutathione S Transferase ◽  
Potential Significance ◽  
Glutathione S Transferases ◽  
Rat Epididymis ◽  
First Time

The presence of the glutathione S-transferases, enzymes that catalyse the conjugation of glutathione with a variety of compounds, is reported here, for the first time, in the mammalian epididymis–vas deferens. These glutathione S-transferases, approx. 50% of those from rat liver on a per-mg-of-protein basis, are resolved by isoelectric focusing into six peaks, each with a characteristic isoelectric point and substrate specificity. By these same criteria, the first three peaks (pI 8.9, 8.2 and 7.8) can be identified as transferases B, A and C respectively. The fifth peak (pI7.2) may correspond to transferase M; the fourth (pI7.5) and sixth (pI7.0) peaks do not correspond to previously described transferases. The distribution of transferase activity towards any one substrate studied differs in sequential sections of the epididymis and vas deferens; in addition, the longitudinal-distribution pattern differs for each of the three substrates studied. Isoelectric focusing of the cytosol fractions of the different sections further substantiates these observations. The potential significance of these enzymes and of their distribution in terms of epididymal function, maturation of spermatozoa, is discussed.

scholarly journals The effect of vitamin A deficiency on hepatic, renal and pulmonary glutathione S-transferase activities in the rat

1980 ◽  
Vol 188 (3) ◽  
pp. 889-893 ◽  
Author(s):  
Z H Siddik ◽  
E G Mimnaugh ◽  
M A Trush ◽  
T E Gram
Keyword(s):  
Vitamin A ◽  
Vitamin A Deficiency ◽  
Nutritional State ◽  
Glutathione S Transferase ◽  
Chemical Carcinogens ◽  
Deficient Diet ◽  
Liver Cytosol ◽  
Weanling Rats ◽  
Glutathione S Transferases ◽  
The Relationship

Feeding male weanling rats on a vitamin A-deficient diet for 6 weeks resulted in significant increases (44-57%) in glutathione S-aryl-, S-aralkyl- S-alkyl- and S-epoxidetransferase activities in the liver cytosol. Only the S-aralkyl- (27%) and S-alkyltransferase (14%) activities were significantly increased in the kidney as a result of deficiency. There was no effect on any of the pulmonary glutathione S-transferase activities. The increases in hepatic transferase activities were due primarily to increases (25-96%) in the apparent Vmax. There were no changes in the apparant Km of any of the four drug substrates employed. With 3,4-dichloronitrobenzene as the second substrate, the apparent Km for glutathione was increased by over 2-fold in vitamin A-deficient livers as compared with controls. The relationship between these results and enhanced susceptibility to chemical carcinogens in vitamin A deficiency is briefly discussed, and comparison is made between the effects of this nutritional state and pretreatment with drug inducers on the glutathione S-transferases.

Effect of inhibitors of glutathione S-transferase on glyceryl trinitrate activity in isolated rat aorta

1993 ◽  
Vol 71 (2) ◽  
pp. 179-184 ◽  
Author(s):  
Rita Nigam ◽  
Tracy Whiting ◽  
Brian M. Bennett
Keyword(s):  
Glyceryl Trinitrate ◽  
Cyclic Gmp ◽  
Guanylyl Cyclase ◽  
Rat Aorta ◽  
Supernatant Fraction ◽  
Organic Nitrates ◽  
Transferase Activity ◽  
Glutathione S Transferase ◽  
Glutathione S Transferases

We investigated the role of glutathione S-transferases (enzymes known to biotransform organic nitrates) in the vascular action of glyceryl trinitrate (GTN). Relaxation of phenylephrine-contracted rat aortic strips was assessed in the presence or absence of the glutathione S-transferase inhibitors Basilen Blue, bromosulfophthalein, Rose Bengal, hematin, chlorotriphenyltin, and (octyloxy)benzoylvinylglutathione. Whereas none of the inhibitors increased the EC50 for GTN relaxation, glutathione S-transferase activity in the 100 000 × g supernatant fraction of rat aorta was inhibited markedly by most of the inhibitors. In addition, GTN-stimulated activation of aortic guanylyl cyclase in broken-cell preparations was attenuated by all of the glutathione S-transferase inhibitors, suggesting a direct inhibitory action on guanylyl cyclase. In other experiments using aortic strips preexposed to phenylephrine, the inhibitors had no effect on GTN-induced cyclic GMP accumulation or on vascular biotransformation of GTN. In contrast, both Basilen Blue and bromosulfophthalein significantly inhibited GTN-induced relaxation of K+-contracted aortic strips, and Basilen Blue significantly inhibited GTN biotransformation in aortic strips preexposed to 25 mM K+. This may be due to a more favourable electrochemical gradient for entry of the inhibitors into membrane-depolarized tissues. We conclude that vascular glutathione S-transferases play a role in mediating the vasodilator actions of GTN in intact tissues in vitro, but that this appears to depend upon the nature of the contractile agent used in such studies.Key words: glyceryl trinitrate, glutathione S-transferase, cyclic GMP, vascular smooth muscle, biotransformation.

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