一株碱性纤维素酶高产菌株的分离、鉴定、系统发育分析及酶学性质的研究

对从土样中分离得到的一株碱性纤维素酶高产菌株H9进行了鉴定,该菌株呈长杆状,革兰氏染色为阳性,产芽孢.通过对其形态、生理生化特性、16S rDNA基因序列(该序列已收录于Genebank,登录号为EF501974)同源性分析的多相分类研究,确定该菌株为短小芽孢杆菌.对酶的性质研究表明,其最适pH值为8,最适温度为55℃,在pH值5～9范围内具有良好的稳定性.

Isolation, Identification, Phylogenetic Analysis and Enzymatic Characteristics of a Strain Producing Alkaline Cellulase

A bacterium with high alkaline cellulase was isolated from soil samples by using CMC plate and shaking flask culture. The strain, named H9, was Gram-positive Bacillus with spore-forming. 16S rDNA gene had been cloned and had been accepted by GeneBank with accession number EF501974. Based on the polyphasic studies, including its phenotypic, physio-biochemical characteristics, 16S rDNA sequence similarity and phylogenetic analysis by using 16S rDNA sequence, H9 was identified as Bacillus pumilus. The characteristics of the enzyme were also studied. The results showed that the optimum pH value of the strain was 8 and the optimum temperature was 55℃. It had both good alkaline endurance and stable enzymatic activity at pH value 5～9 and had remarkable heat stability under 55℃.