Fed-batch production of Thermomonospora fusca endoglucanase by recombinant Streptomyces lividans

The factors affecting the production of a Thermomonospora fusca endoglucanase by a recombinant Streptomyces lividans strain were studied in a fermentor with glucose addition controlled by a pH‐stat. The recombinant plasmid was stable for 35 generations with constant endoglucanase productivity. Glucose and peptone were used as the carbon and nitrogen sources. Addition of Tween‐80 increased endoglucanase production twofold. A significant decrease in endoglucanase production was observed at low aeration. During fed‐batch cultivation, pulse feeding (6 g/L) of a glucose‐ammonium sulfate solution was optimal for endoglucanase production. With higher concentrations of glucose (15 g/L), a significant amount of organic acid, including acetic acid, was produced, which inhibited cell growth and endoglucanase production. Under optimum conditions, 1.7 U/mL of endoglucanase were produced. © 1998 John Wiley & Sons, Inc. Biotechnol Bioeng 60: 70–76, 1998.