Single Nucleotide Polymorphism Analysis of the rpoB Gene Region for Genotyping of Brucella melitensis Strains Isolated from Field in Turkey

We previously described the first molecular characterization of Brucella isolates in Turkey that were examined by single nucleotide polymorphisms (SNPs) at the rpoB locus of B. melitensis strains isolated from adult and pediatric patients. However, the molecular typing of B. melitensis strains causing animal infections in Turkey has not been previously investigated. The aim of this study was to evaluate SNP analysis of rpoB gene of B. melitensis from field isolates in Turkey and to try to find out one of the most appropriate methods other than conventional method for long term evaluation of epidemiological studies. Thirty-two B. melitensis strains isolated from Marmara, Aegean, Mediterranean, Central Anatolia and Eastern Anatolia regions of Turkey were investigated together with 3 reference strains. According to rpoB sequencing results, three distinct genotypes (SNP type 1, type variant 2 and type 2) were recognized. SNP technique characterized the strains at the molecular levels independently from B. melitensis biovars. Our study showed that SNP analysis has a better discriminatory capability in identification of B. melitensis strains compared to classical method. In conclusion, it was suggested that SNP analysis could be useful as a molecular epidemiological method to determine relationships between B. melitensis isolates and might aid in effective surveillance and control method for brucellosis particularly in conjunction with a national databases.