Overproduction of extracellular endoglucanase by genetically engineered Bacillus subtilis

Summary Overproduction of extracellular endoglucanase was attempted by modifying promoter region of an endoglucanase gene cloned from Bacillus subtilis BSE616 and expressing in B. subtilis DB104. A strong promoter was cloned from B. subtilis 168 chromosomal DNA and fused to the endoglucanase gene after removing its native promoter. An effective Shine-Dalgarno sequence was inserted between the promoter and the endoglucanase structural gene. The modified gene was expressed well in B. subtilis and produced 265 units of endoglucanase per mg protein that is 60 % of total protein which was secreted into culture medium.