SYNTHESIS OF GLUTAMIC ACID AND GLUTAMYL POLYPEPTIDE BY BACILLUS ANTHRACIS I

Abstract

B. anthracis produces an active transaminase that catalyzes the synthesis of glutamic acid from aspartic acid and alpha-ketoglutaric acid. Only the L-form of aspartic acid was active and the resulting glutamic acid was the L-form. The enzyme was obtained in cell-free extracts by treating cells in a sonic oscillator. It was purified and obtained in dry form by (NH4)2SO4 precipitation followed by lyophilization. The pH optimum for transaminase in sonic extracts was 7.3 to 7.5. The enzyme was most stable at pH 8.5 to 9. Filtrates of cultures grown in nutrient broth with yeast extract contained the enzyme, but little or no transaminase activity was present in filtrates of cultures grown in a synthetic medium. No glutamyl polypeptide was synthesized by intact cells or cell-free extracts under the conditions of these expts. Methods are described for the detn. of glutamic acid and glutamyl polypeptide.