Optimum culture conditions for production by Pseudomonas chlororaphis B23 of nitrile hydratase.

Abstract

We sought optimum culture conditions for the production by Pseudomonas chlororaphis B23 of nitrile hydratase activity. Addition of ferric and ferrous ions and the use of methacrylamide as an inducer greatly enhanced nitrile hydratase formation. When P. chlororaphis B23 was cultivated for 26 hr at 25°C in a medium consisting of 1 g of sucrose, 0.5 g of methacrylamide, 0.2 g of l-cysteine, 0.2 g of l-glutamate (Na), 0.2g of l-proline, 50 mg of KH2PO4, 50 mg of K2HPO4, 50 mg of MgSO4·7H20, and 1 mg of FeSO4·7H20 per 100 ml of tap water with the pH controlled at pH 7.5 to 7.8, the enzyme activity in the culture broth was 900-times that previously reported.