[Identification of Lactobacillus and Streptococcus thermophilus by PCR amplification and sequence analysis of 16S rRNA].
OBJECTIVE
To develop a PCR method for identifying the 16S rRNA of Lactobacillus and Streptococcus thermophilus at the species level.


METHODS
Optimizing the method for DNA extraction and the conditions for PCR amplification. Joining the PCR amplification products from 16S rRNA to plasmid puc18-T and detecting the sequence.


RESULTS
All 50 isolates recovered from yoghourt products were characterized by 16S rRNA sequence analysis and 7 groups were identified as L. bulgaricus (24 strains), S. thermophilus (12 strains), L. acidophilus (7 strains), L. casei (3 strains), L. delbrueckii (2 strains), L. fermentum (1 strain) and S. lutetiensis (1 strain).


CONCLUSIONS
16S rRNA PCR method developed in this research is a sensitive and reliable method for the identification of both Lactobacillus and Streptococcus thermophilus.
Dong
Yinping
Y
Institute for Nutrition and Food Safety, China CDC, Beijing 100021, China.
Cui
Shenghui
S
Li
Fengqin
F
Yu
Hongxia
H
D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics*; D007778:Lactobacillus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction / Q000379:methods; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D017422:Sequence Analysis, DNA; D013045:Species Specificity; D048249:Streptococcus thermophilus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D015014:Yogurt / Q000382:microbiology
D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S