一株葡聚糖酶产生菌的分离选育及鉴定

Isolation and identification of a glucanase-producing strain

利用葡聚糖平板初筛,三角摇瓶复筛,从土壤样品中中分离得到一株葡聚糖酶高产菌株P5,发酵酶活力可以达到2.5U/mL。菌株呈长杆状、革兰氏染色阳性、产芽孢;生理生化实验结果表明该菌株与枯草芽孢杆菌最为相近;16S rDNA基因序列包含1510个碱基对,同源性分析显示该菌株与枯草芽孢杆菌菌株最为相近,最高相似性为99%,基于16S rDNA基因序列的系统发育分析显示,该菌株与枯草芽孢杆菌菌株CD-6及YPM8的亲缘关系最近,根据以上多相分类结果鉴定该菌株为枯草芽孢杆菌。

A high glucanase-producing strain named P5 was isolated from soil by CMC screening plate and shake flask culture. Its glucanase activity could reach 2.5U/ml. P5 was a Gram-positive, spore-forming and rod bacterium. It was showed that P5 was mostly similar to Bacillus subtilis based on physio-biochemical characters. The 16S rRNA gene sequence of P5 was 1510bp long and highly identical to B. subtilis with a similarity of 99%. The 16S rDNA phylogenetic tree showed that P5 was very close to B. subtilis CD-6 and B. subtilis YPM8. Thereby, P5 was identified as B. subtilis.