Zhang Xueya, Li Qiaoling, Lin Hailong, Zhou Wangxiao, Qian Changrui, Sun Zhewei, Lin Li, Liu Hongmao, Lu Junwan, Lin Xi, Li Kewei, Xu Teng, Zhang Hailin, Li Changchong, Bao Qiyu
Department of Pediatric Respiratory Disease, The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.
Key Laboratory of Medical Genetics of Zhejiang Province, Key Laboratory of Laboratory Medicine, Ministry of Education of China, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, China.
Front Microbiol. 2021 Apr 7;12:636396. doi: 10.3389/fmicb.2021.636396. eCollection 2021.
Aminoglycosides are important options for treating life-threatening infections. However, high levels of aminoglycoside resistance (HLAR) among isolates have been observed to be increasing frequently. In this study, a total of 292 isolates of the complex from a teaching hospital in China were analyzed. Among these isolates, the percentage of HLAR strains was 13.7% (40/292), and 15 aminoglycoside resistance genes were identified among the HLAR strains, with being the most dominant resistance gene (70%, 28/40). We also described an -carrying strain KP2757 that exhibited a high-level resistance to all aminoglycosides tested. Whole-genome sequencing of KP2757 demonstrated that the strain contained one chromosome and three plasmids, with all the aminoglycoside resistance genes (including two copies of and six AME genes) being located on a conjugative plasmid, p2757-346, belonging to type IncHI5. Comparative genomic analysis of eight IncHI5 plasmids showed that six of them carried two copies of the intact gene in the complete or truncated Tn transposon. To the best of our knowledge, for the first time, we observed that two copies of together with six AME genes coexisted on the same plasmid in a strain of with HLAR. Comparative genomic analysis of eight -carrying IncHI5 plasmids isolated from humans and sediment was performed, suggesting the potential for dissemination of these plasmids among bacteria from different sources. These results demonstrated the necessity of monitoring the prevalence of IncHI5 plasmids to restrict their worldwide dissemination.
氨基糖苷类药物是治疗危及生命感染的重要选择。然而，已观察到分离株中高水平氨基糖苷类耐药性（HLAR）的情况频繁增加。在本研究中，对来自中国一家教学医院的该菌属的292株分离株进行了分析。在这些分离株中，HLAR菌株的比例为13.7%（40/292），在HLAR菌株中鉴定出15个氨基糖苷类耐药基因，其中[aac(6')-Iaa]是最主要的耐药基因（70%，28/40）。我们还描述了一株携带[aac(6')-Iaa]的菌株KP2757，它对所有测试的氨基糖苷类药物均表现出高水平耐药。KP2757的全基因组测序表明，该菌株含有一条染色体和三个质粒，所有氨基糖苷类耐药基因（包括两个拷贝的[aac(6')-Iaa]和六个AME基因）均位于一个接合性质粒p2757-346上，该质粒属于IncHI5型。对八个IncHI5质粒的比较基因组分析表明，其中六个在完整或截短的Tn转座子中携带两个拷贝的完整[aac(6')-Iaa]基因。据我们所知，我们首次观察到在一株具有HLAR的肺炎克雷伯菌中，两个拷贝的[aac(6')-Iaa]与六个AME基因共存于同一质粒上。对从人和沉积物中分离出的八个携带[aac(6')-Iaa]的IncHI5质粒进行了比较基因组分析，表明这些质粒在不同来源细菌之间具有传播的可能性。这些结果证明了监测IncHI5质粒流行情况以限制其在全球传播的必要性。
