多重耐药的肉鸡源大肠埃希氏菌基因组完成图及耐药性分析

Complete Genome Sequences and Antimicrobial Resistance Analysis of Two Multi-drug Resistant Escherichia coli Isolated from Broiler Feces

为研究2株分离自宁波某养殖场鸡粪样品中的多重耐药大肠埃希氏菌的耐药机制,采用微量肉汤稀释法检测2株菌的耐药表型、全自动生长曲线测定仪测定细菌生长动力,用第3代PacBio RSII进行全基因组测序。结果显示,菌株ECCHD184和ECCWS199对10种以上抗菌药物耐药。多种抗菌药物联合使用对2株菌生长动力影响较小,反映了其多重耐药。ECCHD184含有质粒pTB211(164062 bp)和pTB212(110417 bp),ECCWS199含有质粒pTB211(162163 bp)和pTB212(159756 bp)。ECCHD184和ECCWS199的质粒上分别有10个和20个获得性耐药基因,并预测到多个接合转移元件和IS,说明质粒上的耐药基因具有传播扩散的潜力。

In order to study the mechanism of multidrug resistance of two Escherichia coli strains isolated from chicken feces of a farm in Ningbo,microbroth dilution method was used to test the drug resistance.In addition,automatic growth curve tester was used to determine the bacterial growth dynamics,and the third generation PacBio RSII was used to sequencing the whole genomes.The results showed that strains ECCHD184 and ECCWS199 were both resistant to more than 10 antimicrobials.The combination of multiple antimicrobials had little effect on the growth dynamics of these two strains,which indicated the high level of multiple drug resistance.There were plasmid pTB211(164062 bp)and pTB212(110417 bp)in ECCHD184;as well as plasmid pTB211(162,163 bp)and pTB212(159756 bp)in ECCWS199.A total of 10 and 20 acquired resistance genes were found in ECCHD184 and ECCWS199 plasmids,respectively.Further,several conjugative transfer elements and IS(insertion sequence)were predicted,indicating that the antimicrobial resistance genes in the plasmids have the potential to spread.