Molecular typing of Campylobacter jejuni strains: comparison among four different techniques

Abstract

This study compared the ability of pulsed-field gel electrophoresis (PFGE), flaA small variable region (SVR) sequencing, analysis of the clustered regularly interspaced short palindromic repeats locus by high resolution melting analysis (CRISPR-HRMA), and multilocus sequence typing (MLST) for typing 111 Campylobacter jejuni strains isolated from diverse sources during 20 years in Brazil. For this, we used previous results obtained by PFGE and flaA-SVR sequencing from our research group and performed CRISPR-HRMA and MLST typing for the first time. Furthermore, the discrimination index (DI) of each method was accessed. The DI for PFGE, flaA-SVR sequencing, CRISPR-HRMA, and MLST was 0.980, 0.932, 0.868, and 0.931, respectively. By PFGE and flaA-SVR sequencing, some strains from clinical and non-clinical sources and from humans and animals presented ≥ 80% similarity. Similarly, some strains from different origins presented the same ST and CRISPR-HRMA types. In conclusion, despite the different DI values, all assays provided the same epidemiological information suggesting that a potential transmission may have occurred between C. jejuni from clinical and non-clinical sources and from animals and humans in Brazil. Furthermore it was demonstrated the suitability of PFGE that should be used preferably together with MLST and/or flaA-SVR sequencing for typing C. jejuni strains.

Core Genome Multilocus Sequence Typing for Food Animal Source Attribution of Human Campylobacter jejuni Infections

“…While this aids in strain differentiation, it also results in a labor-intensive set of five multiplexed PCR reactions. Analyses of the variable regions surrounding the fla gene or CRISPR loci have also been introduced, but these are often used in conjunction with MLST and incur a cost in labor [30].…”

Antimicrobial Resistance Profiles and Phylogenetic Analysis of Campylobacter jejuni Strains Isolated in Brazil by Whole Genome Sequencing

“…The same hypothesis was observed when these C. jejuni strains were typed by flaA-short variable region sequencing and pulsed field gel electrophoresis in a previous study. 17,37 Our findings using whole genome SNP analysis improved the characterization of this important poultry-related pathogen circulating in Brazil, the first exporter and the second largest poultry meat producer worldwide. 38 According to the literature, this is the first study performed in Brazil that used the next generation sequencing technology to assess the phylogenetic relationship of C. jejuni based on whole genome SNP analysis.…”