[Identification and phylogenetic analysis of one strain of Lactobacillus delbrueckii subsp. bulgaricus separated from yoghourt].
OBJECTIVE
For being further applied and studied, one strain of Lactobacillus delbrueckii subsp. bulgaricus (wch9901) separated from yoghourt which had been identified by phenotype characteristic analysis was identified by 16S rDNA and phylogenetic analyzed.


METHODS
The 16S rDNA of wch9901 was amplified with the genomic DNA of wch9901 as template, and the conservative sequences of the 16S rDNA as primers. Inserted 16S rDNA amplified into clonal vector pGEM-T under the function of T4 DNA ligase to construct recombined plasmid pGEM-wch9901 16S rDNA. The recombined plasmid was identified by restriction enzyme digestion, and the eligible plasmid was presented to sequencing company for DNA sequencing. Nucleic acid sequence was blast in GenBank and phylogenetic tree was constructed using neighbor-joining method of distance methods by Mega3.1 soft.


RESULTS
Results of blastn showed that the homology of 16S rDNA of wch9901 with the 16S rDNA of Lactobacillus delbrueckii subsp. bulgaricus strains was higher than 96%. On the phylogenetic tree, wch9901 formed a separate branch and located between Lactobacillus delbrueckii subsp. bulgaricus LGM2 evolution branch and another evolution branch which was composed of Lactobacillus delbrueckii subsp. bulgaricus DL2 evolution cluster and Lactobacillus delbrueckii subsp. bulgaricus JSQ evolution cluster. The distance between wch9901 evolution branch and Lactobacillus delbrueckii subsp. bulgaricus LGM2 evolution branch was the closest.


CONCLUSIONS
wch9901 belonged to Lactobacillus delbrueckii subsp. bulgaricus. wch9901 showed the closest evolution relationship to Lactobacillus delbrueckii subsp. bulgaricus LGM2.
Wang
Chuan
C
Department of Medical Technology, West China School of Public Health, Sichuan University, Chengdu 610041, China.
Zhang
Chaowu
C
Pei
Xiaofang
X
Liu
Hengchuan
H
D001483:Base Sequence; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics; D004275:DNA, Ribosomal / Q000032:analysis / Q000235:genetics; D048668:Lactobacillus delbrueckii / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000379:methods; D012336:RNA, Ribosomal, 16S / Q000032:analysis / Q000235:genetics; D017422:Sequence Analysis, DNA; D015014:Yogurt / Q000382:microbiology*
D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S