THE USE OF MOLECULAR GENETIC METHODS BASED ON MLVA ANALYSIS TO CONFIRM THE UNIQUENESS OF COLLECTION STRAINS OF BRUCELLA

Abstract

Collections of pathogenic bacterial cultures are necessary for the storage of commercially valuable and typical strains for the purpose of patenting, production and testing of diagnostic and preventive drugs, as well as epidemiological strains isolated during the diagnosis of infectious diseases for detailed study and monitoring of changes in sanitary and epidemiological well-being. Collections are replenished with new unique strains, so it is very important that the characteristics of these strains should be carried out using highly discriminatory molecular genetic methods. This article presents the results of the evaluation of the genetic diversity of 36 collection strains of Brucella abortus and 57 strains of Brucella melitensis by the Multilocus variable number tandem repeat (VNTR) analysis (MLVA-16). Generic identification and absence of contamination by other bacterial species was confirmed by sequencing of the 16S rRNA gene. MLVA analysis allowed to establish contamination of 4 strains with different genotypes of brucella and to reveal that the deposited 36 strains isolated in 14 outbreaks of brucellosis are identical genotypes of the pathogen. Our studies have confirmed the presence of identical brucella strains in the collection. The use of MLVA-16 in testing isolated bacterial cultures from a single outbreak will allow differentiating unique strains for their subsequent deposition. Verification of deposited strains with MLVA characteristics with a detailed analysis of metadata about deposited strains will optimize the collection, in terms of preserving only unique strains, which will reduce economic costs and risks to ensure biological safety.