Glutathione-S-transferase, a possible drug-metabolizing enzyme, in Haemonchus contortus: Comparative activity of a cambendazole-resistant and a susceptible strain

Kawalek, Joseph C.; Rew, Robert S.; Heavner, James E.

doi:10.1016/0020-7519(84)90045-6

Cited by 56 publications

(22 citation statements)

References 13 publications

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“…Glutathione S-transferases have been most widely studied in mammalian liver, kidney, and erythrocytes but have been detected also in extracts of certain parasites, such as the cestode Moniezia expansa and the nematodes Ascaris suum and Haemonchus contortus (27,28). In the case of A. suum, enzyme activity has been localized to the intestinal epithelium (27).…”

Section: Discussionmentioning

confidence: 99%

Mr 26,000 antigen of Schistosoma japonicum recognized by resistant WEHI 129/J mice is a parasite glutathione S-transferase.

Smith¹,

Davern²,

Board³

et al. 1986

Proc. Natl. Acad. Sci. U.S.A.

203

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authors request that the following correction be noted. Recent nucleotide sequence analysis has established that a C residue was omitted at position 628 of the Sj26 cDNA sequence presented in Fig. 2. The amended nucleotide sequence and the altered prediction of the COOH-terminal structure of Sj26 are given below. This correction does not otherwise affect the conclusions of the paper. ABSTRACT Mice of the inbred strain 129/J bred at this Institute (WEHI 129/J) are relatively resistant to chronic infection with the parasitic helminth Schistosomajaponicum. In contrast to more permissive mouse strains such as BALB/c, the WEHI 129/J mice are high responders to a Mr 26,000 adult worm antigen designated Sj26. Cloned cDNAs corresponding to Sj26 have been identified in a S. japonicum phage Xgtll amp3 expression library, and their nucleotide sequences have been deduced. The predicted amino acid sequence of the antigen specified by these cDNAs shows striking homology with class it isozymes of mammalian glutathione S-transferases (RX:glutathione R-transferase, EC 2.5.1.18). Extracts of adult worms contain glutathione S-transferase activity, and affinity chromatography of enzyme activity on glutathione columns leads to the purification of a Mr 26,000 molecule that comigrates with Sj26. Although vaccination studies in mice with a .3-galactosidase-Sj26 fusion protein from Escherichia coli are encouraging, more immunogenic preparations of the antigen are likely to be required to establish the utility of Sj26 as a model vaccine.

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Section: Discussionmentioning

confidence: 99%

Mr 26,000 antigen of Schistosoma japonicum recognized by resistant WEHI 129/J mice is a parasite glutathione S-transferase.

Smith¹,

Davern²,

Board³

et al. 1986

Proc. Natl. Acad. Sci. U.S.A.

203

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“…In addition, somatic extracts of cestode and digenean parasites have higher activity towards lipid peroxidation products than nematodes, including H. contortus, do (2, 9). Parasite GSTs have also been associated with drug resistance (18,19). HcGST-1, isolated from a drug-resistant strain of H. contortus, only weakly bound the majority of commercial anthelmintics, with no evidence of enzymatic conjugation (results not shown).…”

Section: Resultsmentioning

confidence: 97%

“…The levels of the phase II detoxification system glutathione transferase (GST) have been shown to increase in parasitic helminths during chronic infection (3). Previous research has attempted to correlate this overexpression with the ability of GST to detoxify immune-initiated cytotoxic products of lipid peroxidation (8, 10) or has associated the overexpression of GST, including H. contortus GST, with drug resistance (18,19). In this paper, we analyze a new GST from the sheep strongylid H. contortus and show that this GST does not appear to have a broad immune defense or drug metabolism role but possibly has a more focused detoxification function within the nematode.…”

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confidence: 99%

Binding of Hematin by a New Class of Glutathione Transferase from the Blood-Feeding Parasitic NematodeHaemonchus contortus

et al. 2004

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The phase II detoxification system glutathione transferase (GST) is associated with the establishment of parasitic nematode infections within the gastrointestinal environment of the mammalian host. We report the functional analysis of a GST from an important worldwide parasitic nematode of small ruminants, Haemonchus contortus. This GST shows limited activity with a range of classical GST substrates but effectively binds hematin. The high-affinity binding site for hematin was not present in the GST showing the most identity, CE07055 from the free-living nematode Caenorhabditis elegans. This finding suggests that the high-affinity binding of hematin may represent a parasite adaptation to blood or tissue feeding from the host.The gastrointestinal blood-feeding nematode Haemonchus contortus represents a major economic burden to agricultural communities worldwide, causing infections resulting in anemia, weight loss, and ultimately death in small ruminants. There are presently no commercial vaccines available for H. contortus infections, and the most effective method of control is a combination of pasture management and the use of chemical agents (anthelmintics). Increasing reports of drug-resistant H. contortus indicate that this current control strategy is not sustainable (26), with chemicals no longer effectively controlling H. contortus infections in several parts of the world (33). Understanding the host-parasite relationship at the mucosal feeding surface is important in identifying new therapeutic approaches. The levels of the phase II detoxification system glutathione transferase (GST) have been shown to increase in parasitic helminths during chronic infection (3). Previous research has attempted to correlate this overexpression with the ability of GST to detoxify immune-initiated cytotoxic products of lipid peroxidation (8, 10) or has associated the overexpression of GST, including H. contortus GST, with drug resistance (18,19). In this paper, we analyze a new GST from the sheep strongylid H. contortus and show that this GST does not appear to have a broad immune defense or drug metabolism role but possibly has a more focused detoxification function within the nematode. MATERIALS AND METHODSIsolation, recombinant expression, and purification of H. contortus GST. mRNA was isolated from adult H. contortus nematodes (CAVR, a drug-resistant strain) with a Quickprep Micro mRNA purification kit (Pharmacia). H. contortus cDNA was obtained with a First Strand cDNA synthesis kit (Pharmacia). The H. contortus GST-encoding DNA was isolated by an established strategy with an upstream primer derived from the N-terminal sequence of the native H. contortus GST protein (27) and a downstream oligo(dT)-based anchor primer (1, 5). The PCR product (approximately 650 bp) was cloned into pUC18 (SureClone ligation kit; Pharmacia), and the insert was sequenced. The H. contortus GST was directionally cloned into pET23d and sequenced in both directions (Long-read LI-COR, GenBank accession number AF281663). The recombinant H. contortu...

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“…The enzymes are known to act in detoxifying xenobiotics by two pathways: conjugation with glutathione and the binding of the enzyme itself to the xenobiotic. However, while they are known to be involved in the detoxification of some anthelmintics (e.g., dichlorvos [46]) and to function in detoxification of endogenous products of lipid peroxidation and in binding various endogenous ligands (e.g., bile acids and steroids), they have been linked to drug resistance in only a single study, which found slightly increased activities in an isolate of H. contortus showing resistance to cambendazole (25). UDPGT enzymes are also known to exist in nematodes, with the H. contortus genome possessing 34 UDPGT genes (26) and C. elegans known to possess 72 genes (47).…”

Section: Discussionmentioning

confidence: 99%

“…Given the previous demonstration of induction of CYP activity by PHB in H. contortus larvae (24) and the presence of GSTs and UDPGTs in this species (25,26), which may be expected to be inducible with PHB, it was apparent that PHB induction may be a useful tool to determine whether these enzyme systems could play a role in the detoxification of NAP. The aim of the present study therefore was to examine the consequences of exposure to PHB on the ability of H. contortus larvae to tolerate NAP.…”

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confidence: 99%

Phenobarbital Induction and Chemical Synergism Demonstrate the Role of UDP-Glucuronosyltransferases in Detoxification of Naphthalophos by Haemonchus contortus Larvae

Kotze

Ruffell

Ingham

2014

Antimicrob Agents Chemother

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We used an enzyme induction approach to study the role of detoxification enzymes in the interaction of the anthelmintic compound naphthalophos with Haemonchus contortus larvae. Larvae were treated with the barbiturate phenobarbital, which is known to induce the activity of a number of detoxification enzymes in mammals and insects, including cytochromes P450 (CYPs), UDP-glucuronosyltransferases (UDPGTs), and glutathione (GSH) S-transferases (GSTs). Cotreatment of larvae with phenobarbital and naphthalophos resulted in a significant increase in the naphthalophos 50% inhibitory concentration (IC 50 ) compared to treatment of larvae with the anthelmintic alone (up to a 28-fold increase). The phenobarbital-induced drug tolerance was reversed by cotreatment with the UDPGT inhibitors 5-nitrouracil, 4,6-dihydroxy-5-nitropyrimidine, probenecid, and sulfinpyrazone. Isobologram analysis of the interaction of 5-nitrouracil with naphthalophos in phenobarbital-treated larvae clearly showed the presence of strong synergism. The UDPGT inhibitors 5-nitrouracil, 4,6-dihydroxy-5-nitropyrimidine, and probenecid also showed synergistic effects with non-phenobarbital-treated worms (synergism ratio up to 3.2-fold). This study indicates that H. contortus larvae possess one or more UDPGT enzymes able to detoxify naphthalophos. In highlighting the protective role of this enzyme group, this study reveals the potential for UDPGT enzymes to act as a resistance mechanism that may develop under drug selection pressure in field isolates of this species. In addition, the data indicate the potential for a chemotherapeutic approach utilizing inhibitors of UDPGT enzymes as synergists to increase the activity of naphthalophos against parasitic worms and to combat detoxification-mediated drug resistance if it arises in the field.

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Glutathione-S-transferase, a possible drug-metabolizing enzyme, in Haemonchus contortus: Comparative activity of a cambendazole-resistant and a susceptible strain

Cited by 56 publications

References 13 publications

Mr 26,000 antigen of Schistosoma japonicum recognized by resistant WEHI 129/J mice is a parasite glutathione S-transferase.

Mr 26,000 antigen of Schistosoma japonicum recognized by resistant WEHI 129/J mice is a parasite glutathione S-transferase.

Binding of Hematin by a New Class of Glutathione Transferase from the Blood-Feeding Parasitic NematodeHaemonchus contortus

Phenobarbital Induction and Chemical Synergism Demonstrate the Role of UDP-Glucuronosyltransferases in Detoxification of Naphthalophos by Haemonchus contortus Larvae

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