高产纤维素酶生二素链霉菌的鉴定与选育研究

Research on the identification and screening of high cellulase-producing Streptomyces ambofaciens strain

从朽木中分离到1株产纤维酶活力高的NC-7菌株,经形态观察和生理生化测定,初步鉴定为放线菌,链霉菌属,生二素链霉菌(Streptomyces ambofaciens)。采用硫酸二乙酯60min与紫外70s、硫酸二乙酯60min与紫外80s的复合诱变方法对NC-7孢子进行诱变,得到产纤维酶活力高的2株菌,即X402菌株、P303菌株,其FPA酶活力分别为2.85IU/mL、2.52IU/mL,比NC-7出发菌株分别提高38.95%、22.44%;CMC酶活力分别为4.83IU/mL、5.29IU/mL,比NC-7出发菌株提高13.21%、23.92%。

Strain NC-7 was screened from putrid wood and had high production activity of cellulase. By morphological observation and physiochemical analysis, it was primarily classified as Streptomyces ambofaciens. Spore mutagenesis was applied to strains NC-7 by compound treatment of 60 min DES-70 s ultraviolet and 60 rain DES-80 s ultraviolet. Two mutants, named X402 and P303, were isolated. Their cellulase-producing activity was about twice as that of strain NC-7. The filter paper activity of X402 and P303 were 28.54 IU/ml and 25.15 IU/ml, that is, 38.95% and 22.44% higher than that of NC-7, respectively. The CMC-Na activity of X402 and P303 were 48.33 IU/ml and 53.90 IU/ml, that is, 13.21% and 23.92% higher than that of NC-7.