Optimization of 7 alpha-hydroxysteroid dehydrogenase production by Escherichia coli 080

7 alpha-Hydroxysteroid dehydrogenase (EC 1.1.1.159) production by Escherichia coli strain 080 was highest when the organism was grown in brain heart infusion broth at pH 6.5 for 72-96 h with shaking at 37 degrees C. The oxygen consumption rate had a strong effect on the production of this constitutive enzyme. Glucose and lactose at 0.2-0.4%, detergents, and ethylenediaminetetra-acetic acid were found to increase the enzyme production.