平菇高产纤维素酶抗降解物阻遏突变株的选育

Screening of the Degradation Repressor Resistance Mutants of High-yield Cellulose Pleurotus ostreatus

平菇在降解富含纤维素的原料时,纤维素酶活性受到降解产物葡萄糖的反馈调节。随着纤维素酶活性的降低,纤维素降解速率下降;通过对平菇菌种进行遗传操作,获得纤维素酶活性较高的菌株,以此来实现平菇的高产。实验对平菇杂-17生产菌株进行氯化锂和亚硝基胍联合诱变处理,利用含葡萄糖结构类似物2-脱氧葡萄糖的纤维素培养基平板进行筛选,得到平菇纤维素酶抗降解物阻遏的突变株。通过对突变株纤维素酶活力的测定,筛选获得了一株纤维素酶活力较平菇原始菌株有明显提高的抗降解物葡萄糖阻遏的菌株。

When Pleurotus ostreatus degradates the raw material which was rich in cellulose, cellulase activity is affected by the feedback regulation of glucose which is degradation - products. With the reducing of cellulase activity, cellulose degrada- tion rate was decreasing rapidly. By genetic operations of Pleurotus ostreatus, we can get a strains in higher cellulase activi- ty, in order to achieve the Pleurotus ostreatus yield . In this study, the production of Pleurotus ostreatus - 17strains was treated by lithium chloride and co - nitrosoguanidine. The mutants which can resist repression of cellulose degradation were selected by cellulose solid medium plate containing 2 - deoxyglucose which is the glucose analogues. With measuring ascer- tain of cellulase activity, we have achieve a Pleurotus ostreatus strain which cellulase activity had significantly improved and anti -degradation glucose repression.