[Classification of domestic probiotic cultures of Lactobacillus genus].

AIM

To study strains of bacteria from Lactobacillus genus using combination of microbiological and molecular biological methods in order to define more accurately their systematic position and biochemical characteristics.

MATERIALS AND METHODS

Thirteen cultures of Lactobacillus bacteria isolated from stool of healthy persons were studied: L. plantarum CS 396, L. plantarum 8-PA-3, L. plantarum 421-2, L. fermentum 90-TC-4, L. delbrueckii gKNM 101, L. delbrueckii gKNM 526, L. acidophilus Er 317/402 NARINE, L. acidophilus 100 ash, L. acidophilus NK-1, L. acidophilus NNIE, L. acidophilus K3sh24, L. brevis gKNM 23 11, L. casei gKNM 577. Their enzymatic activity relative to 50 sugars was studied using API-50 system. Structure of proximal region of 16S rRNA gene was studied also.

RESULTS

According to results of 16S rRNA gene sequence analysis strains were divided on 2 groups: 1) L. casei gKNM 577, L. plantarum 8-PA-3, L. plantarum CS 396, which species belonging corresponded to stated description. Comparison of nucleotide sequence of 16S rRNA gene of group 2 strains with nucleotide sequences database revealed that cultures NK-1, Er315/402 NARINE, 100 ash, NNIE identified early as L. acidophilus belong to species L. helveticus; L. brevis gKNM 23 and L. acidophilus K3sh24--to group L. casei/paracasei, L. delbrueckii gKNM 101 and L. fermentum 90-TC-4--to L. plantarum, L. delbrueckii gKNM 526--to L. fermentum, and L. plantarum 421-2--to L. rhamnosus.

CONCLUSION

Obtained data allowed to perform taxonomic reclassification of species belonging of studied probiotic cultures of lactobacilli according to modem level of systematic of bacteria.