Production of L-asparaginase II by Escherichia coli.

l-Asparaginase II was synthesized at constant rates by Escherichia coli under anaerobic conditions. The enzyme was produced optimally by bacteria grown between pH 7 and 8 at 37 C. Although some enzyme was formed aerobically, between 100 and 1,000 times more asparaginase II was produced during anaerobic growth in media enriched with high concentrations of a variety of amino acids. Bacteria grown under these conditions should provide a rich starting material for the large-scale production of the enzyme. No single amino acid specifically induced the synthesis of the asparaginase, nor did l-asparagine, even when it was used as the only source of nitrogen. The enzyme was produced at lower rates in the presence of sugars; glucose was the most inhibitory.