高产纤维素酶突变株的筛选及其产酶条件优化

通过常压室温等离子体技术诱变里氏木霉RUT-C30，筛选高产纤维素酶突变株，并对其产酶进行优化，提高纤维素酶的产量。筛选得到高产纤维素酶突变株后，进行全基因组测序分析突变型，并对产酶培养基和培养条件进行优化。结果表明：经过筛选获得高产纤维素酶突变株JNDY-13，其摇瓶发酵最高滤纸酶活可达2.21 IU/mL，为出发菌株的2.21 倍，优化后JNDY-13在5 L罐中流加发酵所产最高滤纸酶活为5.40 IU/mL；测序结果显示JNDY-13基因组中共有752 个突变发生，其中半乳糖激酶基因中被插入的18 个碱基可能是突变株纤维素酶活力增加的原因。

Screening of Trichoderma reesei Mutants and Optimization of Fermentation Conditions for Higher Cellulase Production

Mutants of Trichoderma reesei RUT-C30 induced by atmospheric and room temperature plasma (ARTP) were screened for cellulase production. Whole-genome sequencing was performed to analyze the mutation types of the selected mutant. Also, we investigated the optimization of fermentation medium and conditions for improved production of cellulase. Mutant JNDY-13 was found to produce the highest cellulase activity. Through shake-flask fermentation, the filter paper activity (FPA) of JNDY-13 was 2.21 IU/mL, which was 2.21 times higher than that of T. reesei RUT-C30. The highest FPA of 5.40 IU/mL was achieved through fed-batch fermentation in a 5-L fermentor under optimized conditions. A total of 752 mutations were identified in JNDY-13, and the 18-base pair insertion in the galactokinase gene may account for the increased cellulase activity.