%0 Journal Article %A Eze, L. C. %A Echetebu, C. O. %T Some Properties of Aspartate and Alanine Aminotransferases from Trichoderma viride %D 1980 %J Microbiology, %V 120 %N 2 %P 523-527 %@ 1465-2080 %R https://doi.org/10.1099/00221287-120-2-523 %I Microbiology Society, %X Aspartate aminotransferase (EC 2.6.1.1) and alanine aminotransferase (EC 2.6.1.2) were extracted from mycelia of Tricchoderma viride, partially purified and characterized. The pH optima for the enzyme activities were 9·0 and 8·6, respectively. Both enzymes were relatively stable at 37 °C but rapidly denatured at 60 °C. They were inducible by both l-aspartate and dl-alanine, but aspartate was the better inducer. The apparent Michaelis constants for aspartate aminotransferase when l-aspartate and 2-oxoglutarate were used were 7·14 mm and 1·32 mm, respectively. In the case of alanine aminotransferase, using dl-alanine and 2-oxoglutarate the corresponding values were 8·33 mm and 1·85 mm, respectively. The enzymes were competitively inhibited by succinate with K i values of 21 mm and 17 mm for aspartate aminotransferase and alanine aminotransferase, respectively. Both enzymes could use l-methionine whereas only aspartate aminotransferase could use l-tyrosine as amino donor. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-120-2-523