Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, South China Agricultural University, Guangzhou, China; National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou 510642, China.
Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, South China Agricultural University, Guangzhou, China; National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou 510642, China.
Sci Total Environ. 2022 Apr 10;816:151540. doi: 10.1016/j.scitotenv.2021.151540. Epub 2021 Nov 9.
Flower is an essential element in the human lifestyle but its role in disseminating antimicrobial resistance (AMR) between the environment and humans is unclear. In this study, we screened fresh flowers (Lilium spp.) collected from planting bases, market and florists in Guangzhou China aiming to investigate the prevalence of AMR genes, particularly cfr, optrA and poxtA mediating resistance to linezolid, a first-line drug for the treatment of different Gram-positive bacterial infections. We found 223 Enterococcus isolates consisting of Enterococcus faecalis, Enterococcus faecium and Enterococcus mundtii, and >50% of these isolates exhibited multiple-drug resistance. Additionally, 31 optrA-positive Enterococcus including 22 E. faecalis and 9 E. mundtii strains were recovered, however cfr and poxtA were not detected. The 22 E. faecalis strains were belonged to 7 Multilocus sequence types in which ST202 and ST376 were predominant and 9 E. mundtii strains from the same plantation bases were divided into three PFGE groups. Genetically, the majority of optrA were located on the chromosome and shared similar insertion sites and transpositions mediated by Tn554 family members. Plasmid-bearing optrA were identified in 6 E. faecalis strains where IS1216 family played key roles in horizontal transfer of optrA. These findings emphasize that the prevalence of drug resistant Enterococcus in fresh flowers is a latent danger and increases the risk of AMR dissemination to humans from the environment.
花是人类生活方式中不可或缺的一部分，但它在环境与人类之间传播抗微生物药物耐药性（AMR）的作用尚不清楚。在本研究中，我们对中国广州种植基地、市场和花店采集的新鲜花朵（百合属）进行了筛选，旨在调查 AMR 基因（尤其是介导利奈唑胺耐药的 cfr、optrA 和 poxtA）的流行情况，利奈唑胺是治疗不同革兰氏阳性菌感染的一线药物。我们共分离出 223 株肠球菌，包括粪肠球菌、屎肠球菌和屎肠球菌，其中 50%以上的分离株表现出多重耐药性。此外，我们还回收了 31 株 optrA 阳性肠球菌，其中包括 22 株粪肠球菌和 9 株屎肠球菌，但未检测到 cfr 和 poxtA。22 株粪肠球菌属于 7 种多位点序列型，其中 ST202 和 ST376 占优势，来自同一种植基地的 9 株屎肠球菌分为 3 个 PFGE 组。遗传分析显示，大多数 optrA 位于染色体上，具有相似的插入位点和由 Tn554 家族成员介导的转位。在 6 株粪肠球菌中发现了携带 optrA 的质粒，其中 IS1216 家族在 optrA 的水平转移中发挥了关键作用。这些发现强调了新鲜花卉中耐药性肠球菌的流行是一种潜在的危险，增加了环境中 AMR 向人类传播的风险。
