Genotyping of Corynebacterium pseudotuberculosis isolates using PCR-based DNA fingerprinting methods

Phenotypic typing methods are often time consuming and do not adequately discriminate among the strains involved. Innovative molecular techniques can perform direct typing by analyzing DNA and are becoming widespread as important tools for bacterial typing, molecular epidemiology and molecular systematization. The aim of this study was to genotype Corynebacterium pseudotuberculosis strains using PCR-based DNA fingerprinting methods and to evaluate the methods comparatively. Within the scope of the study, 17 C. pseudotuberculosis strains were analyzed. The strains were genotyped by enterobacterial repetitive intergenic consensus (ERIC)-PCR using ERIC2 primer; by random amplified polymorphic (RAPD) DNA-PCR using primers P5, P6, P11, P14, P16, P21 and M13; and by (GTG)5-PCR using (GTG)5 primer. The discrimination power and confidence intervals of the methods were calculated based on the genotyping results using each primer. All strains produced amplification products with the primers used for genotyping. As a result of genotyping with ERIC2, P14, P11, (GTG)5, P21, P5, M13, P6 and P16 primers, the discrimination powers (confidence intervals) were calculated as 0.8603 (0.858-0.862), 0.7132(0.709-0.716), 0.6838(0.668-0.699), 0.6397(0.623-0.656), 0.5809(0.560-0.601), 0.3235(0.293-0.353), 0.1176(0.081-0.153), 0.1176(0.081-0.153) and 0.1176(0.081-0.153), respectively. As a result of the comparative evaluation of the results, it was observed that ERIC2 and P14 primers had high discrimination power and confidence interval in genotyping C. pseudotuberculosis strains, while M13, P6 and P16 primers were insufficient in genotyping of strains. It was concluded that genotyping with ERIC2 and P14 primers can be used reliably in investigating the molecular epidemiology of infections and/or outbreaks caused by C. pseudotuberculosis.