STUDYING THE DIVERSITY OF LACTOCOCCI BACTERIOPHAGES OBTAINED FROM FERMENTED DAIRY PRODUCTS USING MOLECULAR GENETIC METHODS

Abstract

For production of fermented milk products in the territory of the Republic of Belarus, lactic acid bacteria related to p. Lactococcus are used more often. Continuous phage monitoring makes it possible to limit economic losses due to phagolysis at production of fermented milk products, as well as to reduce the risk of contamination of finished products with pathogenic microbiota. It is necessary to identify and determine the properties of bacteriophages for that circulating at enterprises, considering that at each individual enterprise there are no specific types (kinds) of phages, which is due to the assortment of products, types of ferments used and hygiene conditions. The article dwells on studies on isolation and characterization of lactococci bacteriophages. Of the 51 phagocontaining samples of products selected in the territory of the Republic of Belarus, 68 bacteriophages have been isolated. The spectrum of their lytic activity was determined. Based on the results of PCR with species specific primers, 39 bacteriophages are classified as C2 type. One bacteriophage was identified as P335 according to PCR results. 939 type bacteriophages were not detected among the isolated viruses. Differentiation of C2 type lactococcal phages was carried out. A selection of the restriction enzymes allowing to distinguish phages inside the C2 type is carried out. A scheme of intraspecific differentiation of lactococci bacteriophages was developed using RFLP analysis. RFLP-analysis allowed to divide 39 lactophages of type C2 into six groups. Acknowledgements. The work was carried out within the framework of research under task 9.5.50 “Study of species diversity of lactic acid bacteria obtained from natural sources, variability of lactococci phages obtained at milk processing plants, depending on season and region” of GPNI “Innovative technologies in agro-industrial complex”.