[Numerical taxonomy of bifidobacteria and homology analysis of some representative strains].
Fifty five strains of bifidobacteria belonging to Bifidobacterium from various sources were studied by using numerical taxonomic techniques. These organisms included 13 reference strains and 42 newly isolated strains (19 strains of human sources, 25 strains of animal sources and 11 strains obtained from sewage). Several strains isolated from the animals weren't isolated before. Overall similarities of the strains for 75 characters contained morphological, physiological and biochemical characteristics and antibacterial susceptibility were determined. Dendrogram of numerical analysis based on unweighted pair cluster average linkage were achieved. Five clusters were defined at 70% Sm level. The relationships of these strains among five clusters were analysed. The strains of human sources were basically separated from the animal strains, and the sewage strains were distributed between the animal clusters and the human clusters. On the basis of the numerical analysis, the G + C content of DNA of some representative strains among these clusters were measured. Biotin-labeled DNA segments, complementary to variable regions of 16S rRNA, were amplified using PCR as probes. In the dot-blot hybridization the relationships of DNA segments among some strains were discussed. The test results showed that the homologies among the strains in same species and various species were different. The studies are valuable for further research in the relationships of some species among bifidobacteria of various sources.
Ling
D
D
Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080.
Zhou
Y
Y
Yuan
Q
Q
D000818:Animals; D001644:Bifidobacterium / Q000145:classification* / Q000235:genetics*; D004269:DNA, Bacterial / Q000032:analysis; D006801:Humans; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D012722:Sewage / Q000382:microbiology
D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; D012722:Sewage