Collect. Czech. Chem. Commun. 1981, 46, 2766-2773

Properties and characteristics of partly purified glutamate dehydrogenase from sheep rumen mucosa

Katarína Holovskáa, Viera Lenártováa and Ivan Havassyb

a Department of Pathological Physiology, Biochemistry and Toxicology, School of Veterinary Medicine, 040 00 Košice
b Institute of Physiology of Farm Animals, Slovak Academy of Sciences, 040 00 Košice


The purification of glutamate dehydrogenase from sheep rumen mucosa on DEAE-cellulose afforded two enzyme fractions with glutamate dehydrogenase activity. The enzyme fraction II (tissue glutamate dehydrogenase) was freed of contaminating proteins in the subsequent purification step on Sephadex G-200. The approximate relative molecular weight (260 000) of tissue glutamate dehydrogenase (fraction II) was determined by gel filtration on Sephadex G-200 and the approximate relative molecular weight of its polypeptide chain (48 000) was established by polyacrylamide gel electrophoresis in SDS. The pH-optimum of fraction II was 7.9. The effect of substrate concentration on the rate of the enzymatic reaction was examined and the following apparent Michaelis' constants were found for the individual substrates: NADH 6.25 . 10-5 mol/l, 2-oxoglutarate 4.5 . 10-3 mol/l, and NH4+ 77 . 10-3 mol/l.