Wang Mingyu, Wang Wenjia, Niu Yu, Liu Ting, Li Ling, Zhang Mengge, Li Ziyun, Su Wenya, Liu Fangyue, Zhang Xuhua, Xu Hai
State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China.
Laboratory Medicine Center, The Second Hospital of Shandong University, Jinan, China.
Front Microbiol. 2020 Dec 10;11:590357. doi: 10.3389/fmicb.2020.590357. eCollection 2020.
An extensively-drug resistant (XDR) W60 was isolated from the urine sample of a patient. The genetic basis for its XDR phenotype was investigated, particularly the basis for its resistance toward β-lactam/BLI (β-Lactamase Inhibitor) combinations. Following determination of the XDR phenotype, third generation genomic sequencing was performed to identify genetic structures in W60. Further cloning analysis was performed to identify determinants of β-lactam/BLI combination resistance. It was found that W60 is resistant to nearly all of the tested antibiotics including all commonly used β-lactam/BLI combinations. Analysis of the genomic structures in W60 showed two novel transferable plasmids are responsible for the resistance phenotypes. Further genetic analysis showed leads to high resistance to β-lactam/BLI combinations, which was enhanced by co-expressing . pECW602 harbors a truncated that is not functional due to the loss of the N-terminal signal peptide coding region. Research performed in this work leads to several significant conclusions: the XDR phenotype of W60 can be attributed to the presence of transferable multidrug resistance plasmids; NDM-5 confers high resistance to β-lactam/BLI combinations; co-expression of enhances resistance caused by NDM-5; the signal peptides of TEM type β-lactamases are essential for their secretion and function. Findings of this work show the danger of transferable multidrug resistance plasmids and metallo-β-lactamases, both of which should be given more attention in the analysis and treatment of multidrug resistant pathogens.
从一名患者的尿液样本中分离出一株广泛耐药（XDR）的W60。对其XDR表型的遗传基础进行了研究，特别是其对β-内酰胺/β-内酰胺酶抑制剂（BLI）联合制剂耐药的基础。确定XDR表型后，进行了第三代基因组测序以鉴定W60中的遗传结构。进一步进行克隆分析以鉴定β-内酰胺/BLI联合制剂耐药的决定因素。结果发现，W60对几乎所有测试抗生素耐药，包括所有常用的β-内酰胺/BLI联合制剂。对W60基因组结构的分析表明，两种新型可转移质粒导致了耐药表型。进一步的遗传分析表明，导致对β-内酰胺/BLI联合制剂高度耐药，通过共表达增强了这种耐药性。pECW602含有一个截短的，由于N端信号肽编码区缺失而无功能。本研究得出了几个重要结论：W60的XDR表型可归因于可转移的多药耐药质粒的存在；NDM-5赋予对β-内酰胺/BLI联合制剂高度耐药；的共表达增强了由NDM-5引起的耐药性；TEM型β-内酰胺酶的信号肽对其分泌和功能至关重要。本研究结果表明了可转移的多药耐药质粒和金属β-内酰胺酶的危险性，在分析和治疗多重耐药病原体时，这两者都应得到更多关注。
