ACTIVITIES OF ENZYMES OF CARBOHYDRATE AND ENERGY-METABOLISM OF THE SPORES OF THE MICROSPORIDIAN, NOSEMA-GRYLLI

The presence of 14 enzymes was investigated using purified spores of t he microsporidian Nosema grylli from fat body of the crickets Gryllus bimaculatus. Glucose 6-phosphate dehydrogenase (EC 1.1.1.49), phosphog lucomutase (EC 5.4.2.2), phosphoglucose isomerase (EC 5.3.1.9), fructo se 6-phosphate kinase (EC 2.7.1.11), aldolase (EC 4.1.2.13), 3-phosoph oglycerate kinase (EC 2.7.2.3), pyruvate kinase (EC 2.7.1.40) and glyc erol 3-phosphate dehydrogenase (EC 1.1.1.8) were detected with activit ies of 15 +/- 1, 7 +/-: 1, 1,549 +/- 255, 10 +/- 1, 5 +/- 1, 16 +/- 4, 6 +/- 1 and 16 +/- 2 nmol/min.mg protein, respectively. Hexokinase (E C 2.7.1.1), NAD-dependent malate dehydrogenase (EC 1.1.1.37), malic en zyme (EC 1.1.1.40), lactate dehydrogenase (EC 1.1.1.27), alcohol dehyd rogenase (EC 1.1.1.1) and succinate dehydrogenase (EC 1.3.99.1) were n ot detectable. These results suggest the catabolism of carbohydrates i n microsporidia occurs via the Embden-Meyerhof pathway. Glycerol 3-pho sphate dehydrogenase may reoxidize NADH which is produced by glycerald ehyde 3-phosphate dehydrogenase in glycolysis.