Effects of glycerol of beta-lactamase production during high cell density cultivation of recombinant Escherichia coli.

Recombinant Escherichia coli was cultured up to OD600 90 with glycerol fed by the DO-STAT method to produce recombinant beta-lactamase. Optimum feeding and induction conditions were determined. When glycerol was maintained at a high concentration (40-50 g/L) after isopropyl thiogalactoside (IPTG) induction at OD600 75, a 2-fold increase in the amount of soluble beta-lactamase was obtained. Similarly, a 3-fold increase was obtained by the addition of NaCl (0.4 M) at low glycerol concentration (10 g/L).