Incorporation of ammonium in amino acids by Trypanosoma cruzi.
Ammonium ions were incorporated into L-glutamate and alpha-ketoglutarate in epimastigote forms of Trypanosoma cruzi through the following enzymatic systems: NADPH and NADH-dependent glutamate dehydrogenase, NADPH-dependent glutamate synthase, L-glutamine synthetase and NADH-dependent glutamate synthase in order of decreasing specific activity (mumoles of product formed/min/mg protein). The pH optima and Km's for the glutamate dehydrogenase system were determined. Disc electrophoresis showed the presence of cathodic bands of GDH activity, which were highly dependent on NADP+.
D000641:Ammonia / Q000378:metabolism*; D000818:Animals; D005969:Glutamate Dehydrogenase / Q000378:metabolism; D005970:Glutamate Synthase / Q000378:metabolism; D005974:Glutamate-Ammonia Ligase / Q000378:metabolism; D005971:Glutamates / Q000096:biosynthesis*; D005973:Glutamine / Q000096:biosynthesis*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D009243:NAD / Q000494:pharmacology; D009249:NADP / Q000494:pharmacology; D014349:Trypanosoma cruzi / Q000201:enzymology / Q000378:metabolism*
D005971:Glutamates; D005973:Glutamine; D009243:NAD; D009249:NADP; D000641:Ammonia; D005970:Glutamate Synthase; D005969:Glutamate Dehydrogenase; D005974:Glutamate-Ammonia Ligase