摘要

人们越来越担心细菌病原体对抗生素和消毒剂的耐药性。本研究通过对广州地区即食（RTE）肉制品中分离的大肠埃希菌的药敏特征、超广谱β-内酰胺酶( ESBLs )、质粒介导的喹诺酮类耐药基因( PMQRs )和季铵盐类复合耐药基因( QACs )进行分析，并确定这些基因在大肠杆菌中是否共定位。从720份RTE肉样中分离到64株大肠杆菌。70.3 %的分离菌株存在多药耐药性。100 %的菌株对苯扎氯铵耐药。在16株产ESBL的大肠杆菌分离株中鉴定出四种类型的β-内酰胺酶基因：blaSHV（9.4％），blaTEM（7.8％），blaCTX-M-15（1.6％）和blaCTX-M-9（1.6 ％）。在9株分离菌中存在PMQRs（14.1％），分别在8个（12.5％）和1株分离菌（1.6％）中检测到aac（6'） - Ib-cr和qnrD。QACs ydgE / ydgF最常见( 60.9 % )，而qacF，mdfA，sugE（p），emrE，qacG，sugE（c）和qacE不太普遍（1.6％-18.8％）。21株分离物中（32.8％）同时存在ESBLs和/或PMQRs与QAC。在一个分离株中发现AAC ( 6′) - ib- Cr和blaCTX - M - 15基因与qacF共转移。本研究的结果表明，与QACs结合的ESBLs和/或PMQRs不仅可以共定位，而且可以在RTE肉制品中的大肠杆菌分离物中共转运。具有多种抗微生物抗性基因的大肠杆菌分离物可能通过食物链传播给人类，因此需要进一步研究和提高认识。

There are growing concerns about the coselection of resistance against antibiotics and disinfectants in bacterial pathogens. The aim of this study was to characterize the antimicrobial susceptibility profiles, the prevalence of extended-spectrum β-lactamases (ESBLs), plasmid-mediated quinolone resistance genes (PMQRs), and quaternary ammonium compound resistance genes (QACs) in Escherichia coli isolated from ready-to-eat (RTE) meat products obtained in Guangzhou, China, and to determine whether these genes were colocalized in the isolates. A total of 64 E. coli isolates were obtained from 720 RTE meat samples. Multidrug resistance was observed in 70.3% of the isolates. A 100% of the isolates were resistant to benzalkonium chloride. Four types of β-lactamase genes were identified in the 16 ESBL-producing E. coli isolates: blaSHV (9.4%), blaTEM (7.8%), blaCTX-M-15 (1.6%), and blaCTX-M-9 (1.6%). PMQRs were present in nine isolates (14.1%), with aac(6′)-Ib-cr and qnrD detected in eight (12.5%) and one isolate (1.6%), respectively. The QACs ydgE/ydgF were most commonly present (60.9%), while qacF, mdfA, sugE(p), emrE, qacG, sugE(c), and qacE were less prevalent (1.6%–18.8%). Coexistence of ESBLs and/or PMQRs with QACs was found in 21 isolates (32.8%). The aac(6′)-Ib-cr and blaCTX-M-15 genes were found to be cotransferred with qacF in one isolate. The data obtained in this study indicate that ESBLs and/or PMQRs with QACs can not only be colocalized but can also be cotransferred in E. coli isolates from RTE meat products. The E. coli isolates with multiple antimicrobial resistance genes may transmit to humans through food chain and thus require further investigation and increased awareness.

https://www.liebertpub.com/doi/abs/10.1089/fpd.2016.2191