9Hodgson J.The changing bulk catalysis market:recombinant DNA techniques have changed bulk enzyme production dramatically[J].Bio/Technology,1994,12:789-790.
10Yang M Y,Ferrari E.Cloning of the neut ral protease gene of Bacillus sublitis and the use of the cloned gene to create an in vitro-derived deletion mutation[J].J Bacteriol,1984,160:15-21.