成人粪便中长双歧杆菌长亚种的分离鉴定及多位点序列分型分析

为了对成人粪便中分离的长双歧杆菌长亚种进行多位点序列分型分析,采用改良MRS培养基从健康成人粪便中分离的长双歧杆菌长亚种,通过生理生化试验结合16S rDNA和热应激蛋白60(heat-shock protein,hsp60)同源性分析鉴定分离株,利用同源性分析及多位点序列分型(multilocus sequence typing,MLST)技术进一步分析长双歧杆菌长亚种的基因多态性。从12个健康成人体内分离得到24株厌氧的细菌菌株,经形态学观察、生理生化试验、16S rDNA及hsp60同源性分析发现,其中14株分离株为长双歧杆菌长亚种(Bifidobacterium longum subsp. longum)。MLST结果表明:14株长双歧杆菌长亚种可分为10种基因型,且均与Bifidobacterium longum subsp. longum ATCC 15707为不同基因型。健康成人粪便中分离的长双歧杆菌长亚种具有较大的基因多态性。

Isolation,Identification and Multilocus Sequence Typing Analysis of Bifidobacterium longum subsp. longum from Adult Faeces

The aim of this experiment was to perform multilocus sequence typing(MLST)analysis of Bifidobacterium longum subsp. longum isolated from adult faeces. B. longum subsp. longum were isolated from the healthy adult faeces with modified MRS media. And in order to identify and analyse polymorphism of Bifidobacterium longum subsp. longum,the experiment used physiological and biochemical experiments combined with 16S rDNA,heat-shock protein(hsp60)homology analysis and MLST. Twenty four anaerobic strains were isolated from twelve healthy adults in this study,and fourteen strains were identified as Bifidobacterium longum subsp. longum according to physical and biochemical experiments,16S rDNA and hsp60 homology analysis. The results of MLST showed that 14 strains of Bifidobacterium longum subsp. longum belonged to 10 genotypes,and they were all different genotypes from the Bifidobacterium longum subsp. longum ATCC 15707. There are larger differences in genetic polymorphism of Bifidobacterium longum subsp. longum isolated from adult faeces.