Study on the Differences of Virulence Genes and Molecular Typing in Campylobacter Jejuni Isolates from Poultry Products and Diarrhea Patients in Shenzhen / 现代检验医学杂志

ABSTRACT

Objective To understand the differences of virulence genes and molecular typing in Campylobacterjejuni isolates from poultry products and diarrhea patients in Shenzhen.Methods According to specific primers,four virulence genes (cdtB,cadF,flaA,virB1 1 )of C.jejuni were detected by polymerase chain reaction (PCR).Molecular typing for C.jejuni strains was performed by Pulsed-field gel electrophoresis (PFGE).Results There were no differences of gene distribution (cdtB+,cadF+,virB1 1-)between isolates from poultry products and diarrhea patients.Two virulence genes of cdtB and cadF were found in all of ten C.jejuni strains lacking virB1 1 .The carriage rate of flaA in food-borne isolates (3/5 )was higher than those in patient isolates (2/5).In the PFGE map,the clustering analysis of C.jejuni strains showed that a total of 5 to 9 DNA bands were observed in ten strains through the digestion of Sam I.There was high homology (above 85%) between food-borne isolates and patients isolates,but the distribution of flaA in these highly homologous strains was differ-ent.Conclusion So far,C.jejuni strains with cdtB,cadF and flaA were present in Shenzhen,and showed high diversity and homology.This implies that the occurrence of diarrhea in patients with C.jejuni was associated with the contaminated poul-try products by this pathogen.Their findings can provide basic data and evidences about diarrheal disease caused by food-borne C.jejuni for the local region.