Study On The Molecular Epidemiological Features Of Yersinia Enterocolitica Which Harbored The YstB Gene In Parts Of China

Objective To investigate the distribution of ystB gene, which come from Yersinia enterocolitica in parts of China. To detect and analyze other virulence genes, biotype, serotype, genotype, antibiotic sensitivity, and the overall epidemiology characteristics among Yersinia enterocolitica which harbored the ystB gene in this study.Methods Yersinia enterocolitica was cultured by routine method, and identified with the API 20E. The ystB gene was detected by PCR from all the strains. Sequences alignment and analysis will be performed if necessary. The strains which harbored the ystB gene will be selected and detected as follows: the virulence genes (yadA,virF,ail and ystA) was detected by PCR method; The biotype was detected by BE (bile esculin) decompose method and confirmed by other biochemical tests; the serotype was detected by routine serum agglutination; the antibiotic sensitivity test of the stain which harbored the ystB gene was performed by the ATB antibiogram method of bioMerieux; the genotype was analyzed by PFGE, and cluster analysis was performed by BioNumerics software.Result The ratio of strains which harbored ystB gene in Yersinia enterocolitica was 38.1%. The other virulence gene was not detected among the strains which harbored the ystB gene in Yersinia enterocolitica. All of them were biotype 1A. The serotype mainly was O: 6,30, and then was the 0:8, 0:7,8, 0:5 among the strains. Most of them were resistant to amoxicillin, cefalotin, ticarcillin etc, and all of them were sensitive to ciprofloxacin and amikacin. The PFGE was produced 167 patterns and named K6GN11CB0001- K6GN11CB0167 in order.Conclusion The strains harbored ystB gene in Yersinia enterocolitica without carried the virulence gene yadA,virF,ail and ystA. The ystB gene was only carried by biotype 1A. The serotype of Yersinia enterocolitica which harbored the ystB gene was heterogeneity. The 0:8 Y.enterocolitica strain in our country was biotype 1A and didn't carried the other virulence genes, which was different from the 0:8 in other countries. Most of the strains were resistant to amoxicillin and part of cephalosporins, which probably contribute to the expressedβ- lactamase. To analyze the PFGE of Yersinia enterocolitica which harbored the ystB gene, indicated the pulstype was more difference among the strains. Therefore, PFGE can not be used to detect genotype effectively in Yersinia enterocolitica which harbored the ystB gene.