纳豆芽胞杆菌16S rRNA基因的克隆及其系统进化分析

Cloning and phylogenetic analysis of 16S rRNA gene of Bacillus subtilis natto

纳豆芽胞杆菌是从豆豉中分离出的一种具有益生功能的芽胞杆菌。该研究从纳豆芽胞杆菌提取基因组DNA,以芽胞杆菌16S rRNA基因的通用引物,用PCR方法成功扩增出纳豆芽胞杆菌的部分16S rRNA基因,所克隆序列长1 435 bp,G+C含量为55%,该序列已被G eneB ank收录,其编号为AY 864812。BLA ST分析结果显示,AY 864812与G eneB ank中收录的枯草芽胞杆菌16S rRNA基因同源性最高,其中与AY 601722的同源性为100%。用C lusta lx 1.8对相关序列进行系统进化分析,结果显示纳豆芽胞杆菌与枯草芽胞杆菌在进化关系上的地位最近,从分子水平上证实了纳豆芽胞杆菌是枯草杆菌的1个亚种。

Bacillus subtilis natto,isolated from soybean,was one kind of important and potential probiotics bacterium. But there were some taxonomic controversy between B. subtilis vat. natto and B. subtilis. In this study, partial sequence of B. subtilis vat. natto 16S rRNA gene was amplified by polymerase chain reaction （PCR） using the universal Bacillus primers,which its length was 1 435 base-pair（bp） and it was recorded in GeneBank and named as AY864812. The BLAST analysis and phylogenetic analysis indicated that AY864812 was the most similarity with reported 16S rRNA gene of B. subtilis. Therefore,it revealed that B. subtilis natto was a subspecies of B. subtilis.