[Aspartate aminotransferase activity of different strains of Escherichia coli]

Aspartate-aminotransferase activity was measured in strains of Escherichia coli grown no meat infusion broth. As an enzyme cells with damaged permeability of the cytoplasmatic membrane were used. The cells were damaged by an addition of toluene at a concentration of 1% of the reaction mixture by volume. These cells showed 50--60% aspartate-aminotransferase activity as compared with aliquotes of the cell-free extract. E. coli synthesized oxalacetic and glutamic acids from L-aspartic acid and alpha-ketoglutaric acid. Glutamic acid was identified by thin-layer chromatography on Fixion plates. E. coli str. 85 cells and their extracts grown on the synthetic medium containing glucose or glycerol showed a two-fold specific aspartate-aminotransferase activity as compared with those cultivated on meat-infusion broth.