title: Sedimentation properties of native and proteolysed preparations of ox glutamate dehydrogenase.
abstract: The concentration-dependent aggregation behaviour of purified ox liver and brain glutamate dehydrogenase preparations was compared with that of commercially-obtained preparations of the liver enzyme, which have recently been shown to have suffered proteolytic cleavage. Although there were no significant differences in these effects, the presence of 3 mM-GTP and 3 mM-NADH had markedly different effects on the two types of preparation. In this situation, at higher protein concentrations the commercially obtained preparations existed in a higher degree of aggregation than those which had not suffered proteolysis. Studies of the effects of GTP and NADH concentrations on the sedimentation coefficients at a fixed enzyme concentration suggested these effects to be largely due to differences in the affinities of the two preparations for nucleotides.
mesh_terms: D000818:Animals; D001921:Brain / Q000201:enzymology; D002417:Cattle; D002499:Centrifugation, Density Gradient; D005969:Glutamate Dehydrogenase / Q000302:isolation & purification*; D006160:Guanosine Triphosphate / Q000494:pharmacology; D008099:Liver / Q000201:enzymology; D046911:Macromolecular Substances; D009243:NAD / Q000494:pharmacology
chemical_list: D046911:Macromolecular Substances; D009243:NAD; D006160:Guanosine Triphosphate; D005969:Glutamate Dehydrogenase