Xie Lianyan, Dou Yi, Zhou Kaixin, Chen Yue, Han Lizhong, Guo Xiaokui, Sun Jingyong
Department of Clinical Microbiology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine Shanghai, China.
Department of Burns and Plastic Surgery, Ruijin Hospital, Shanghai Jiaotong University School of Medicine Shanghai, China.
Front Microbiol. 2017 Feb 2;8:133. doi: 10.3389/fmicb.2017.00133. eCollection 2017.
To describe the genetic environment, transferability, and antibiotic susceptibility of one clinical isolate harboring both and on different plasmids from a Chinese hospital. The isolate was subjected to antimicrobial susceptibility testing and multilocus sequence typing using Etest and PCR. The plasmids harboring and were analyzed through conjugation experiments, S1-nuclease pulsed-field gel electrophoresis, and hybridization with specific probes. Plasmid DNA was sequenced using Pacbio RS II and annotated using RAST. RJ119, carrying both and , was resistant to almost all carbapenems, cephalosporins, fluoroquinolone, and aminoglycosides and belonged to ST307. was located on a 61,748-bp IncL/M conjugative plasmid, which displayed overall nucleotide identity (99%) to pKPN-E1-Nr.7. was located on a 335,317-bp conjugative plasmid, which was a fusion of a -harboring InA/C plasmid pNDM-US (140,825 bp, 99% identity) and an IncFIB plasmid pKPN-c22 (178,563 bp, 99% identity). The transconjugant RJ119-1 harboring was susceptible to carbapenem, and there was an insertion of IS into the gene. This is the first report of the coexistence of and in one clinical isolate in China. OXA-48 in RJ119 contributed to the majority to its high resistance to carbapenems, whereas NDM-1 remained unexpressed, most likely due to the insertion of IS. Our results provide new insight for the relationship between genetic diagnosis and clinical treatment. They also indicate that increased surveillance of is urgently needed in China.
描述来自一家中国医院的一株临床分离菌的遗传环境、可转移性及抗生素敏感性，该分离菌在不同质粒上同时携带了 blaOXA - 48 和 blaNDM - 1。对该分离菌使用 Etest 和 PCR 进行药敏试验及多位点序列分型。通过接合实验、S1 - 核酸酶脉冲场凝胶电泳以及与特异性探针杂交对携带 blaOXA - 48 和 blaNDM - 1 的质粒进行分析。使用 Pacbio RS II 对质粒 DNA 进行测序，并使用 RAST 进行注释。同时携带 blaOXA - 48 和 blaNDM - 1 的 RJ119 对几乎所有碳青霉烯类、头孢菌素类、氟喹诺酮类和氨基糖苷类抗生素耐药，属于 ST307。blaOXA - 48 位于一个 61,748 - bp 的 IncL/M 接合性质粒上，该质粒与 pKPN - E1 - Nr.7 的总体核苷酸同一性为 99%。blaNDM - 1 位于一个 335,317 - bp 的接合性质粒上，它是一个携带 blaNDM - 1 的 InA/C 质粒 pNDM - US（140,825 bp，同一性 99%）和一个 IncFIB 质粒 pKPN - c22（178,563 bp，同一性 99%）的融合体。携带 blaOXA - 48 的接合子 RJ119 - 1 对碳青霉烯类敏感，并且在 blaOXA - 48 基因中有 IS 的插入。这是中国首次关于一株临床分离菌中 blaOXA - 48 和 blaNDM - 1 共存的报道。RJ119 中的 OXA - 48 是其对碳青霉烯类高度耐药的主要原因，而 NDM - 1 未表达，很可能是由于 IS 的插入。我们的结果为基因诊断与临床治疗之间的关系提供了新的见解。它们还表明中国迫切需要加强对 blaNDM - 1 的监测。
