title: Paragonimus westermani: a cytosolic glutathione S-transferase of a sigma-class in adult stage.
abstract: We purified cytosolic glutathione S-transferase (GST) of adult Paragonimus westermani monitoring its activity with 1-chloro-2,4-dinitrobenzene (CDNB). The enzyme was purified 18.4-fold to electrophoretic homogeneity with 21% recovery rate through a three-step procedure. The purified enzyme (Pw28GST) has a subunit molecular weight of 28 kDa with an isoelectric point at 4.6. Monoclonal antibody (anti-Pw28GST) against Pw28GST did not cross-react with GSTs from other helminths. cDNA library was constructed in lambdaZAP II bacteriophage and screened with anti-Pw28GST. The corresponding gene containing a single open reading frame of 804 bp encoded 211 amino acids. The predicted amino acid sequence exhibited a higher homology with catalytic domain near N-terminus of class sigma GSTs (58%) than with schistosome 28-kDa GSTs (45-41%) or with class sigma GSTs themselves (33-31%). The sequence contained both Tyr-6 and Tyr-10 that are highly conserved in mammalian and helminth GSTs. The apparent K(m) value of a recombinant enzyme was 0.78 mM. Both native and recombinant enzymes showed the highest activity against CDNB, relatively weak activity against ethacrynic acid and reactive carbonyls, and no activity against epoxy-3-(p-nitrophenoxy)-propane. The activities were inhibited by bromosulfophthalein, cibacron blue, and albendazole, but not by praziquantel. These findings indicate that adult P. westermani has a class sigma GST.
authors.affiliation: Department of Parasitology, College of Medicine, Chung-Ang University, Seoul, 156-756.
authors.forename: S J
authors.initials: SJ
authors.lastname: Hong
authors.forename: S Y
authors.initials: SY
authors.lastname: Kang
authors.forename: Y B
authors.initials: YB
authors.lastname: Chung
authors.forename: M H
authors.initials: MH
authors.lastname: Chung
authors.forename: Y J
authors.initials: YJ
authors.lastname: Oh
authors.forename: I
authors.initials: I
authors.lastname: Kang
authors.forename: Y Y
authors.initials: YY
authors.lastname: Bahk
authors.forename: Y
authors.initials: Y
authors.lastname: Kong
authors.forename: S Y
authors.initials: SY
authors.lastname: Cho
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015152:Blotting, Northern; D002852:Chromatography, Ion Exchange; D003600:Cytosol / Q000201:enzymology; D004285:Dogs; D004591:Electrophoresis, Polyacrylamide Gel; D005982:Glutathione Transferase / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D015151:Immunoblotting; D007525:Isoelectric Focusing; D007527:Isoenzymes / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010238:Paragonimus / Q000201:enzymology*; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D016415:Sequence Alignment; D013379:Substrate Specificity
chemical_list: D007527:Isoenzymes; D011994:Recombinant Proteins; D005982:Glutathione Transferase