产纤维素酶嗜热细菌R-250的分离、鉴定

Study on isolation,identification of a thermophilic cellulose-degrading bacteria and conditions for celluase production

利用海南某温泉附近腐烂朽木及土壤,经富集培养分离筛选出高产纤维素酶的嗜热细菌R-250,经形态学和生理生化特性研究以及16S rDNA序列分析鉴定该菌株为地衣芽孢杆菌(Bacillus licheniformis)。以复筛培养基进行培养时,该菌生长的最适温度为50℃,最适pH值为5～6。在该条件下,以玉米秸秆为唯一碳源的产酶培养基产酶培养4d后CMCase酶活达到最高值为14.7IU/mL,滤纸酶活为6.74IU/mL。

A bacterial R-250 strain was isolated from decayed wood and soil around hot spring in Hainan.The R-250 strain was identified as Bacillus licheniformis based on the results of physiology,biochemical characteristics and the homological analysis of 16S rDNA sequence.The strain R-250 showed the optimal pH was at 5～6 and the optimal temperature was at 50℃.The highest enzyme activities with the filter paper and CMCase could go up to 6.74IU/mL and 14.7IU/mL respectively.