Objective: In order to study the biodiversity of Lactobacilli from Northern Tibet in China, we developed enterobacterial repetitive intergenic consensus sequence polymerase chain reaction (ERIC-PCR) technique.
Methods: Seventy seven Lactobacillus strains were isolated from traditional fermented milk products which are made by herd man families in Northern Tibet of China. By ERIC-PCR technique method, using NTSYS-pc2.1 software, we investigated the biodiversity of the strains.
Results: The amplified bands of ERIC-PCR were clear and stable with high repetition and high polymorphisms. The cluster analysis showed that at level 0.73, 77 tested strains were clustered into 4 groups: A1: strains of Lactobacillus casei (35.06% of the strains), A2: strains of Lactobacillus fermentum (61.04% of the strains), A3: strains of Lactobacillus helveticus and A4: strains of Lactobacillus plantarum. The biodiversity of the isolates from Aland A2 groups was further investigated. A1 could be divided into 5 genotypes at the similarity of 80.0%. A2 could be divided into 6 genotypes at the similarity of 84.0%.
Conclusion: Using ERIC-PCR technique, Lactobacilli from Northern Tibet could be distinguished at species level.