Purification and characterization of phosphoglycerate kinase from Fasciola hepatica.
Phosphoglycerate kinase (EC 2.7.2.3) of Fasciola hepatica was purified 375-fold to homogeneity. The enzyme was monomeric, and had a molecular weight of 47 900 and a sedimentation coefficient of 3.0-3.5 S. The enzyme was composed of 397 amino acids and was relatively rich in sulfur amino acids containing 13 methionine and 2 cysteine residues per mole. The enzyme possessed a highly reactive essential sulfhydryl group and was inhibited irreversibly by iodoacetamide and N-ethylmaleimide and reversibly by p-chloromercuribenzoate and 5,5'-dithio-bis(2-nitrobenzoic acid). Initial velocity studies suggested that reaction occurred via a sequential mechanism. The Km values for 3-phosphoglycerate and ATP were 1.26 and 0.90 mM, respectively. ADP was a noncompetitive inhibitor with respect to both ATP and 3-phosphoglycerate.
D000596:Amino Acids / Q000032:analysis; D005210:Fasciola hepatica / Q000201:enzymology*; D008433:Mathematics; D008970:Molecular Weight; D010735:Phosphoglycerate Kinase / Q000037:antagonists & inhibitors / Q000302:isolation & purification*; D013438:Sulfhydryl Compounds / Q000494:pharmacology
D000596:Amino Acids; D013438:Sulfhydryl Compounds; D010735:Phosphoglycerate Kinase