抗高浓度葡萄糖阻遏的纤维素酶高产菌的选育

以本室保存的一株纤维素酶产量较高的拟康氏木霉为出发菌株,经紫外诱变处理,用葡萄糖( 梯度浓度) 纤维素双层平板选育,在含葡萄糖(4% ) 纤维素双层平板上获得一株葡萄糖浓度高达10% 仍能产生纤维素水解透明圈的突变株UVⅢ.培养6 d ,干曲的CMC 酶活、FP 酶活和βG 酶活分别可达1145 .7 u/g 、55 .6 u/g 和24 u/g .分别是出发株的2 .4 倍、3.4 倍和12 .6 倍.

PREPARATION OF A MUTANT KESISTANT TO GLUCOSE REPRESSION

A mutant from Trichoderma pseudokoningii, which can synthesize cellulases when high concentration glucose exists, was obtained by using agar plate screening techniques. The mutant strain was isolated from the agar plate, which contains 4% glucose. This strain is resistant to catabolite repression by glucose and it produced clear catalytic zones on agar plates with 10% glucose. In solid state fermentation, the mutant strain produced high CMCase, FPase, and beta-Gase activities, which were 1145.7 u/g dry weight, 55.6 u/g dry weight, 24.0 u/g dry weight after 6 days' culturing. And these were 2.4, 3.4,12.6 times that of the starting strain, respectively.