Division of Biotechnology, College of Life Sciences, Korea University, Seoul, 02841, Republic of Korea.
Laboratory of Food Safety and Evaluation, Department of Biotechnology, Korea University Graduate School, Seoul, 02841, Republic of Korea.
J Glob Antimicrob Resist. 2021 Mar;24:363-369. doi: 10.1016/j.jgar.2021.01.009. Epub 2021 Jan 28.
To investigate the distribution and genetic characteristics of linezolid-resistant enterococci.
Enterococcus faecalis and Enterococcus faecium strains were isolated from pigs, equipment, grounds, and employees of 19 Korean swine farms in 2017. Antimicrobial susceptibility testing was then performed and linezolid resistance genes were detected via PCR. For genetic epidemiological characterization, multilocus sequence typing and whole-genome sequencing data were analysed.
Twenty-eightE. faecalis and five E. faecium strains were isolated from 1026 samples obtained from the 19 farms. Ten sequence types were identified among the E. faecalis strains, of which ST256 (42.9%) and ST86 (25%) were the most abundant. The oxazolidinone and phenicol resistance genes poxtA, optrA, and fexA were detected in isolates of E. faecalis (100%, 85.7%, and 67.9%, respectively) and E. faecium (100%, 60%, and 80%, respectively). The minimum inhibitory concentrations of linezolid in these isolates ranged from 2 mg/L to 12 mg/L. The whole-genome sequencing data indicated that fexA was located upstream of poxtA.
This is the first study to report the detection of poxtA in isolates that were both susceptible and resistant to linezolid in Korea. These results demonstrate the importance of antimicrobial resistance monitoring programmes, including regular antimicrobial susceptibility testing and resistance gene expression analysis, to facilitate the control of the spread of antibiotic resistance in non-clinical settings in Korea.
研究耐利奈唑胺肠球菌的分布和遗传特征。
2017 年，从韩国 19 个养猪场的猪、设备、地面和员工中分离出粪肠球菌和屎肠球菌。然后进行抗菌药物敏感性试验，并通过 PCR 检测利奈唑胺耐药基因。为了进行遗传流行病学特征分析，分析了多位点序列分型和全基因组测序数据。
从 19 个农场的 1026 份样本中分离出 28 株粪肠球菌和 5 株屎肠球菌。在粪肠球菌菌株中鉴定出 10 种序列类型，其中 ST256（42.9%）和 ST86（25%）最为丰富。在粪肠球菌（100%、85.7%和 67.9%）和屎肠球菌（100%、60%和 80%）分离株中检测到了唑烷酮和苯唑西林耐药基因 poxtA、optrA 和 fexA。这些分离株的利奈唑胺最小抑菌浓度范围为 2mg/L 至 12mg/L。全基因组测序数据表明，fexA 位于 poxtA 的上游。
这是首次在韩国报告检测到对利奈唑胺敏感和耐药的分离株中存在 poxtA。这些结果表明，有必要实施抗菌药物耐药性监测计划，包括定期进行抗菌药物敏感性试验和耐药基因表达分析，以促进在韩国非临床环境中控制抗生素耐药性的传播。
