Purification and characterization of prostaglandin-H E-isomerase, a sigma-class glutathione S-transferase, from Ascaridia galli.
Comparison of partial primary sequences of sigma-class glutathione S-transferases (GSH) of parasitic helminths and a GSH-dependent prostaglandin (PG)-H D-isomerase of rat immune accessory cells suggested that some of the helminth enzymes may also be involved in PG biosynthesis [Meyer and Thomas (1995) Biochem. J. 311, 739-742]. A soluble GSH transferase of the parasitic nematode Ascaridia galli has now been purified which shows high activity and specificity in the GSH-dependent isomerization of PGH to PGE, comparable to that of the rat spleen enzyme in its isomerization of PGH to PGD, and similarly stimulates the activity of prostaglandin H synthase. The enzyme subunit is structurally related to the rat spleen enzyme and sigma-class GSH transferases of helminths according to the partial primary sequence. The data support the hypothesis that some sigma-class GSH transferases of helminth parasites are involved in PG biosynthesis which, in the case of PGE, is likely to be associated with the subversion or suppression of host immunity. A PG-H E-isomerase of comparable specificity and activity has not previously been isolated.
Department of Biochemistry and Molecular Biology, University College, London, U.K.
D J
DJ
Meyer
R
R
Muimo
M
M
Thomas
D
D
Coates
R E
RE
Isaac
D000595:Amino Acid Sequence; D000818:Animals; D000837:Anion Exchange Resins / Q000378:metabolism / Q000494:pharmacology; D001197:Ascaridia / Q000201:enzymology*; D005982:Glutathione Transferase / Q000145:classification* / Q000302:isolation & purification / Q000378:metabolism; D015801:Helminth Proteins / Q000145:classification* / Q000302:isolation & purification / Q000378:metabolism; D019746:Intramolecular Oxidoreductases; D007535:Isomerases / Q000302:isolation & purification* / Q000378:metabolism*; D007700:Kinetics; D008969:Molecular Sequence Data; D000071876:Prostaglandin-E Synthases; D011458:Prostaglandins E / Q000096:biosynthesis; D051381:Rats; D012117:Resins, Synthetic; D012680:Sensitivity and Specificity
D000837:Anion Exchange Resins; D015801:Helminth Proteins; D011458:Prostaglandins E; D012117:Resins, Synthetic; C042855:Mono Q; D005982:Glutathione Transferase; D007535:Isomerases; D019746:Intramolecular Oxidoreductases; D000071876:Prostaglandin-E Synthases