scholarly journals Rat lung glutathione S-transferases. Evidence for two distinct types of 22000-Mr subunits

1984 ◽  
Vol 221 (3) ◽  
pp. 609-615 ◽  
Author(s):  
S V Singh ◽  
C A Partridge ◽  
Y C Awasthi
Keyword(s):  
Rat Liver ◽  
The Other ◽  
Rat Lung ◽  
Glutathione S Transferase ◽  
Substrate Specificities ◽  
Liver Glutathione ◽  
Immunological Properties ◽  
Glutathione S Transferases

Two immunologically distinct types of 22000-Mr subunits are present in rat lung glutathione S-transferases. One of these subunits is probably similar to Ya subunits of rat liver glutathione S-transferases, whereas the other subunit Ya′ is immunologically distinct. Glutathione S-transferase II (pI7.2) of rat lung is a heterodimer (YaYa′) of these subunits, and glutathione S-transferase VI (pI4.8) of rat lung is a homodimer of Ya′ subunits. On hybridization in vitro of the subunits of glutathione S-transferase II of rat lung three active dimers having pI values 9.4, 7.2 and 4.8 are obtained. Immunological properties and substrate specificities indicate that the hybridized enzymes having pI7.2 and 4.8 correspond to glutathione S-transferases II and VI of rat lung respectively.

scholarly journals Two immunologically distinct Yc-type subunits are present in rat lung glutathione S-transferases

1984 ◽  
Vol 224 (1) ◽  
pp. 335-338 ◽  
Author(s):  
S V Singh ◽  
Y C Awasthi
Keyword(s):  
Glutathione Peroxidase ◽  
Rat Liver ◽  
Peroxidase Activity ◽  
Gel Electrophoresis ◽  
Rat Lung ◽  
Glutathione Peroxidase Activity ◽  
Glutathione S Transferase ◽  
Two Dimensional Gel Electrophoresis ◽  
Glutathione S Transferases

Two types of 25 000-Mr subunits are present in rat lung glutathione S-transferase I (pI 8.8). These subunits, designated Yc and Yc', are immunologically and functionally distinct from each other. The homodimers YcYc (pI 10.4) and Yc'Yc' (pI 7.6) obtained by hybridization in vitro of the two subunits of glutathione S-transferase I (pI 8.8) were isolated and characterized. Results of these studies indicate that only the Yc subunits express glutathione peroxidase activity and cross-react with the antibodies raised against glutathione S-transferase B (YaYc) or rat liver. The Yc' subunits do not express glutathione peroxidase activity and do not cross-react with the antibodies raised against glutathione S-transferase B of rat liver. The amino acid compositions of these two subunits are also different. These two subunits can also be separated by the two-dimensional gel electrophoresis of glutathione S-transferase I (pI 8.8) of rat lung.

scholarly journals Different forms of human liver glutathione s-transferases arise from dimeric combinations of at least four immunologically and functionally distinct subunits

1985 ◽  
Vol 232 (3) ◽  
pp. 781-790 ◽  
Author(s):  
S V Singh ◽  
D D Dao ◽  
C A Partridge ◽  
C Theodore ◽  
S K Srivastava ◽  
...  
Keyword(s):  
Human Liver ◽  
Human Lung ◽  
The Other ◽  
Two Dimensional ◽  
Liver Glutathione ◽  
Enzyme Form ◽  
Glutathione S Transferases ◽  
B Subunits ◽  
Subunit Hybridization

Four immunologically distinct subunits were characterized in glutathione (GSH) S-transferases of human liver. Five cationic enzymes (pI 8.9, 8.5, 8.3, 8.2 and 8.0) have an apparently similar subunit composition, and are dimers of 26 500-Mr (A) and 24 500-Mr (B) subunits. A neutral enzyme, pI 6.8, is a dimer of B-type subunits. One of the anionic enzymes, pI 5.5, is also a dimer of 26 500-Mr subunits. However, the 26 500-Mr subunits of this anionic enzyme form are immunologically distinct from the A subunits of the cationic enzymes, and have been designated as A'. Immunoabsorption studies with the neutral enzyme, BB, and the antibodies raised against the cationic enzymes (AB) indicate that A and B subunits are immunologically distinct. Hybridization in vitro of the A and B subunits of the cationic enzymes (AB) results in the expected binary combinations of AA, AB and BB. Studies with the hybridized enzyme forms indicate that only the A subunits express GSH peroxidase activity. A' subunits have maximum affinity for p-nitrobenzyl chloride and p-nitrophenyl acetate, and the B subunits have highest activity towards 1-chloro-2,4-dinitrobenzene. The other anionic form, pI 4.5, present in liver is a heterodimer of 22 500-Mr (C) and B subunits. The C subunits of this enzyme are probably the same as the 22 500-Mr subunits present in human lung and placental GSH transferases. The distinct immunological nature of B and C subunits was also demonstrated by immunoaffinity and subunit-hybridization studies. The results of two-dimensional polyacrylamide-gel-electrophoretic analyses indicate that in human liver GSH transferases, three charge isomers of Mr 26 500 (A type), two charge isomers of Mr 24 500 (B type) and two charge isomers of Mr 22 500 (C type) subunits are present.

scholarly journals Characterization of methylation of rat liver cytosolic glutathione S-transferases by using reverse-phase h.p.l.c. and chromatofocusing

1990 ◽  
Vol 270 (2) ◽  
pp. 483-489 ◽  
Author(s):  
J A Johnson ◽  
T L Neal ◽  
J H Collins ◽  
F L Siegel
Keyword(s):  
Rat Liver ◽  
Time Course ◽  
Glutathione S Transferase ◽  
Reverse Phase ◽  
Cytosolic Glutathione ◽  
Glutathione S Transferases ◽  
Rat Liver Cytosol ◽  
Gst Activity

Glutathione S-transferase (GST) subunits in rat liver cytosol were separated by reverse-phase h.p.l.c.; five major proteins were isolated and identified as subunits 1, 2, 3, 4 and 8. F.p.l.c. chromatofocusing resolved the affinity-purified GST pool into nine different isoenzymes. The five basic (Alpha class) dimeric peaks of GST activity were 1-1, 1-2a, 1-2b, 2-2a and 2-2b. Reverse-phase h.p.l.c. analysis revealed that subunit 8 was also present in the protein peaks designated 1-1, 1-2a and 1-2b. The four neutral (Mu class) isoenzymes were 3-3, 3-4, 3-6 and 4-4. The GST pool was methylated in vitro before reverse-phase h.p.l.c. or f.p.l.c. chromatofocusing. Chromatofocusing indicated that the Mu class isoforms (3-3, 3-4 and 4-4) were the primary GSTs methylated, and h.p.l.c. analysis confirmed that subunits 3 and 4 were the major methyl-accepting GST subunits. The addition of calmodulin stimulated the methylation in vitro of GST isoenzymes 3-3, 3-4 and 4-4 by 3.0-, 7.5- and 9.9-fold respectively. Reverse-phase h.p.l.c. also indicated that only the methylation of GST subunits 3 and 4 was stimulated by calmodulin. Basic GST isoenzymes were minimally methylated and the methylation was not enhanced by calmodulin. Investigation of the time course of methylation of GST subunits 3 and 4 indicated that at incubation times less than 4 h the methylation of both Mu class subunits was stimulated by calmodulin, and that under such conditions subunit 4 was the preferred substrate. In contrast, there was essentially no calmodulin-stimulated methylation at incubation times of 4 or 6 h, and the methylation of subunit 3 was predominant. Kinetic parameters at 2 h of incubation were determined in the presence and in the absence of calmodulin. The addition of calmodulin doubled the Vmax. for methylation of both subunits 3 and 4 and decreased the Km of subunit 4 for S-adenosyl-L-methionine 3.6-fold. Finally, methylation was substoichiometric and after 6 h of incubation ranged from 2.8 to 7.6% on a mole-to-mole basis for subunits 4 and 3 respectively.

scholarly journals Studies on the subunit composition of rat liver glutathione S-transferases.

1983 ◽  
Vol 258 (18) ◽  
pp. 11321-11325 ◽  
Author(s):  
A B Frey ◽  
T Friedberg ◽  
F Oesch ◽  
G Kreibich
Keyword(s):  
Rat Liver ◽  
Subunit Composition ◽  
Liver Glutathione ◽  
Glutathione S Transferases

scholarly journals The nucleotide sequence of a rat liver glutathione S-transferase subunit cDNA clone.

1984 ◽  
Vol 259 (9) ◽  
pp. 5536-5542
Author(s):  
H C Lai ◽  
N Li ◽  
M J Weiss ◽  
C C Reddy ◽  
C P Tu
Keyword(s):  
Nucleotide Sequence ◽  
Rat Liver ◽  
Cdna Clone ◽  
Glutathione S Transferase ◽  
Liver Glutathione

Cytosolic glutathione S-transferases of Oesophagostomum dentatum

Parasitology ◽  
2008 ◽  
Vol 135 (10) ◽  
pp. 1215-1223 ◽  
Author(s):  
A. JOACHIM ◽  
B. RUTTKOWSKI
Keyword(s):  
Amino Acids ◽  
Pcr Primers ◽  
Mrna Levels ◽  
Fourth Stage ◽  
Glutathione S Transferase ◽  
Cdna Sequences ◽  
Oesophagostomum Dentatum ◽  
Cytosolic Glutathione ◽  
Glutathione S Transferases

SUMMARYOesophagostomum dentatum stages were investigated for glutathione S-transferase (GST) expression at the protein and mRNA levels. GST activity was detected in all stages (infectious and parasitic stages including third- and fourth-stage larvae of different ages as well as males and females) and could be dose-dependently inhibited with sulfobromophthalein (SBP). Addition of SBP to in vitro larval cultures reversibly inhibited development from third- to fourth-stage larvae. Two glutathione-affinity purified proteins (23 and 25 kDa) were detected in lysates of exsheathed third-stage larvae by SDS-PAGE. PCR-primers were designed based on peptide sequences and conserved GST sequences of other nematodes for complete cDNA sequences (621 and 624 nt) of 2 isoforms, Od-GST1 and Od-GST2, with 72% nucleotide similarity and 75% for the deduced proteins. Genomic sequences consisted of 7 exons and 6 introns spanning 1296 bp for Od-GST1 and 1579 and 1606 bp for Od-GST2. Quantitative real-time-PCR revealed considerably elevated levels of Od-GST1 in the early parasitic stages and slightly reduced levels of Od-GST2 in male worms. Both Od-GSTs were most similar to GST of Ancylostoma caninum (nucleotides: 73 and 70%; amino acids: 80 and 73%). The first three exons (75 amino acids) corresponded to a synthetic prostaglandin D2 synthase (53% similarity). O. dentatum GSTs might be involved in intrinsic metabolic pathways which could play a role both in nematode physiology and in host-parasite interactions.

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