Study On Antimicrobial Resisitance Of C.Jejuni And Its Related Gene

Since the 1970s, C.jejuni has been generally considered as the main cause leading to the intestinal infection throughout the world. Antibiotics are used when Severe infection and delayed enteritis occurred. With widely use of the antibiotics, the Antimicrobial Resistance of C.jejuni is worldwide focused, while few researches have been reported in China.In our study, 47 C.jejuni was isolated from 307 fowl appendix contents, and Antimicrobial Resistance of these bacterium was tested by disk diffusion technique. The result indicated that 31.9% c.jejuni demonstrated resistance to Ciprofloxacin, the high level of resistance seen were to ampicillin (85.1%), Clindamycin (83.0%), and erythromycin (83.0%), and c.jejuni were more sensitive to furaxone (85.1%)and gentamicin(74.5%). Combined resistance was observed on 89.4% c.jejuni. Genotyping was conducted by RAPD assay was used. 5 straps were observed, whose molecular mass was between 100bp-1500bp. 47 c.jejuni was divided into six(â… ,â…¡,â…¢,â…£,â…¤,â…¥) groups according to the difference of amplified products on electrophoregram. There was 14(29.8%)C.jejuni in Groupâ…¡, which was dominated in these six groups, while there were10 (21.3%), 9 (19.1%), 9 (19.1%), 4 (8.5%), 1 (2.1%) C.jejuni in groupâ… ,â…¢,â…£,â…¤,â…¥respectively.MAMA PCR(mismatch amplification mutation assay PCR ) was used to detected the mutation of gyrA. The result indicated that 15 c.jejuni which were showed resistance to Ciprofloxacin have mutation at amino acid position 86 in the gyrA sequence of C. jejuni isolates, while other 30 sensitive ones have no mutation. Additionally, mutation was detected in one of the C.jejuni which was intermediate to Ciprofloxacin, and the mutation was confirmed by sequencing.