洁净室环境中一株细菌bd5的分离鉴定及系统发育分析

对一株从药品检验洁净室中分离得到的环境菌bd5进行系统分类鉴定。该菌株的16S rDNA序列测序及系统发育分析结果显示,bd5属于罗氏菌属(Rothia),与该属的7个种系统发育关系最密切,因基因序列相似性皆大于95.8%而聚为一簇。虽然bd5与污泥罗氏菌(Rothia amarae)单独相聚,形成一个独立亚分支,但序列差异性达1.8%。生理生化试验结果进一步表明该菌不仅有罗氏菌"属"级的生化特征,还具有与其他种相区别的生化反应。综合形态学特征、生化特性、16S rDNA序列相似性及系统发育关系分析显示,菌株bd5可能为罗氏菌属的一个潜在新种。

Identification and Phylogenetic Analysis of Strain bd5 Isolated from the Clean Room

A bacterium strain bd5,isolated from the clean room for pharmaceutical test,was subjected to a polyphasic taxonomic study.The results of phylogenetic analysis of the bacterium based on its 16S rDNA sequence showed that it belongs to the genus Rothia,and was closely related to seven species of the genus Rothia with 16S rDNA gene sequence similarity values higher than 95.8%.Though forming a coherent phyletic cluster,the strain bd5 had a genomic 16S rDNA sequence difference of 1.8% with Rothia amarae.Biochemical characteristics supported the assignment of this strain to the genus Rothia and distinguished it from the type strains of all validly described Rothia species.Therefore,morphological,biochemical and phylogenetic characteristics demonstrated that the strain bd5 should be classified in the genus Rothia and supposed to be a potential new species.