台州市动物食品中肺炎克雷伯菌质粒介导产AmpC酶的耐药表型与基因型分析

An analysis of the drug resistant phenotype and the genotype of the pneumoniae Klebsiella plasmid produced AmpC β-lactamase in animal foodstuffs in Taizhou

目的探讨动物食品中肺炎克雷伯菌质粒介导产Amp C酶的耐药表型与基因型,以控制动物食品中的细菌耐药性在动物、环境和人类之间的传播。方法采用头孢西丁纸片扩散法筛选产Amp C酶菌株;采用三维试验确证产Amp C酶;采用聚合酶链反应(PCR)和DNA测序检测分析Amp C酶基因型别;采用UNIQ-10柱式质粒小量抽提试剂盒提取细菌质粒。结果 67株肺炎克雷伯菌经头孢西丁敏感试验选出疑产Amp C酶菌株15株,经三维试验确证产Amp C酶菌株有12株,15株疑产Amp C酶菌株经PCR检测和DNA测序证实有10株菌株均为DHA-1型Amp C酶。结论动物食品中分离的肺炎克雷伯菌产Amp C酶的菌株检出率较高,基因型以DHA-1型为主,并且产Amp C酶的肺炎克雷伯菌表型与基因型不完全相同,二者的结果有一定的关联性但同时存在差异。临床兽医应慎用β-内酰胺类药物,动物食品加工更应严格操作规程,切断动物食品链传递给人类。

Objective To study the resistance characteristics and the genotype of pneumoniae Klebsiella plasmid mediated Amp C β- lactamase in animal foodstuffs,so as to control the spreading of drug- resistant- bacterium in environment and among animals and human. Methods Amp C enzyme bacteria strains were screened with cefoxitin disk diffusion methods. Furthermore,the Amp C enzyme was confirmed by a three- dimensional test,and the genotype of Amp C enzyme was analyzed by polymerase chain reaction（ PCR） and confirmed by sequencing; Using UNIQ- 10 column plasmid kit to extract bacterial plasmids. Results From the tested 67 Klebsiella pneumoniae,15 strains were suspected Amp C enzyme producing,within which 12 were confirmed by 3D test,and 10 were detected positive at by PCR and confirmed as DHA- 1 type by sequencing. Conclusion From the Klebsiella pneumoniae which were extracted from animal foodstuff,Amp C enzyme producing strain was detect high and the genotype is mainly DHA- 1,but their phonotype and genotype are not the same,the both results have a certain correlation,but there are some differences. Veterinary clinic should use β- lactam drugs with caution,animal food processing should meet operation rules more strictly,so as to cut off the animal food chain transfer to humans.