Virulence-associated gene detection and ERIC-PCR typing of Campylobacter jejuni strains isolated from foods in four Southern Chinese provinces

Abstract:

Abstract:［Objective］To know food contamination and genetic diversity of Campylobacter jejuni in four provinces of South China，and to provide data for C. jejuni-associated foodborne disease prevention and control.［Methods］According to the national standard and the most probable number(MPN) method，we detected the contamination of C. jejuni from 558 food samples including vegetables，meat product，cooked food，seafood，frozen food，dairy product and edible fungi during 2011 and 2012．The isolates were used to detect 12 virulence-associated genes with PCR methods and construct ERICPCR fingerprints.［Results］Fourteen positive samples were determined from 558 samples，and all positive samples come from meat product samples．The average value of MPN of positive samples was 8.77 MPN/g．Virulence-associated gene analysis reveals that more than 50% of the C.jejuni isolates had at least 9 virulence genes．Interestingly，virB11 gene was not found and the genes of pldA and wlaN were 14.30% in all isolates．Total of 15 C．jejuni isolates could be divided into 10 genotypes belonging to 3 clusters by ERIC-PCR fingerprints.［Conclusion］Meat product was the main source of C. jejuni food contamination in four provinces of South China．More control measures must be taken to avoid C．jejuni contamination.

Key words:Keywords: Campylobacter jejuni，ERIC-PCR typing，virulence-associated genes