Cai Heng, Zhu Yiwei, Hu Dandan, Li Yue, Leptihn Sebastian, Loh Belinda, Hua Xiaoting, Yu Yunsong
Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China.
Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China.
Front Microbiol. 2021 Jul 5;12:674974. doi: 10.3389/fmicb.2021.674974. eCollection 2021.
Many strains of the opportunistic pathogen have acquired resistance to multiple antibiotics. Carbapenem-resistant poses a global healthcare problem due to limited therapeutic options for the treatment of infections. Plasmids and integrative and conjugative elements (ICEs) are the major vectors of antibiotic-resistance gene transfer. In our study, four carbapenem-resistant strains of were isolated from the same patient in a tertiary referral hospital in China, one of these was resistant to gentamicin and tobramycin. In this strain P33, we observed a non-transferable plasmid, pP33-2, carrying a novel gene segment (IS- -IS--ORF--IS), which we concluded to have been formed by IS-mediated gene cluster translocation. In addition, by comparing the chromosomes of the strains that belong to the same sequence type, we identified an ICE, ICEP33, adjacent to a prophage. The L site of ICEP33 is identical to the terminal part of the R site of the prophage. The ICEP33 element contains the transposon Tn, which encodes antibiotic and metal resistance genes. The insertion of ICEP33 in the chromosome mediates resistance to multiple antibiotics. Our study contributes to the understanding of the acquisition of antibiotic resistance in facilitated by mobile genetic elements.
许多机会性病原体菌株已获得对多种抗生素的耐药性。耐碳青霉烯类病原体由于治疗感染的治疗选择有限，构成了一个全球性的医疗问题。质粒和整合与接合元件（ICEs）是抗生素耐药基因转移的主要载体。在我们的研究中，从中国一家三级转诊医院的同一名患者中分离出四株耐碳青霉烯类病原体菌株，其中一株对庆大霉素和妥布霉素耐药。在该P33菌株中，我们观察到一个不可转移的质粒pP33 - 2，它携带一个新的基因片段（IS - -IS - -ORF - -IS），我们推断该片段是由IS介导的基因簇易位形成的。此外，通过比较属于同一序列类型的病原体菌株的染色体，我们鉴定出一个与原噬菌体相邻的ICE，即ICEP33。ICEP33的L位点与原噬菌体R位点的末端部分相同。ICEP33元件包含转座子Tn，其编码抗生素和金属抗性基因。ICEP33插入染色体介导对多种抗生素的耐药性。我们的研究有助于理解移动遗传元件促进病原体获得抗生素耐药性的机制。
