一株同时产KPC-2和NDM-5碳青霉烯酶的肺炎克雷伯菌耐药基因特征分析  

Genomic characteristics of a Klebsiella pneumoniae strain coproducing carbapenemases KPC-2 and NDM-5

作　　者：肖伟强 屈元晔 王小昆 孙明月 常彦敏 许青霞 毕利军[3] Xiao Weiqiang;Qu Yuanye;Wang Xiaokun;Sun Mingyue;Chang Yanmin;Xu Qingxia;Bi Lijun(Department of Clinical Laboratory,Affiliated Cancer Hospital of Zhengzhou University,Zhengzhou 450007,China;Zhengzhou Key Laboratory for Diagnosis of Digestive System Tumor Markers,Zhengzhou 450007,China;Foshan Branch of Institute of Biophysics,Chinese Academy of Sciences,Foshan 528000,China)

机构地区：[1]郑州大学附属肿瘤医院检验科,郑州450007 [2]郑州市消化系统肿瘤标志物诊断重点实验室,郑州450007 [3]中国科学院生物物理所佛山分所,佛山528000

出　　处：《中华微生物学和免疫学杂志》2022年第9期669-675,共7页Chinese Journal of Microbiology and Immunology

基　　金：河南省医学科技攻关计划(LHGJ20210182)。

摘　　要：目的分析一株同时产KPC-2和NDM-5碳青霉烯酶的肺炎克雷伯菌耐药基因特征。方法肺炎克雷伯菌KPN-hnqyy分离自我院血液科一位患者的粪便标本,使用仪器BD Phenix-M50鉴定菌株并测定最小抑菌浓度;酶联免疫层析试验和PCR方法检测碳青霉烯酶基因型;接合试验检测相关质粒的转移性;PacBio和Illumina平台对菌株全基因组测序,并在BacWGSTdb数据库中检索菌株MLST分型、耐药基因和质粒类型,使用软件Easyfig_2.2.3比对基因组和开放读码框序列,BRIG v0.95生成可视化质粒圈图。结果肺炎克雷伯菌KPN-hnqyy对碳青霉烯类抗生素耐药,MLST分型为ST11型,bla_(KPC-2)和blaNDM-5碳青霉烯酶基因阳性;接合子bla_(KPC-2)基因阳性,blaNDM-5阴性;全基因组测序显示菌株含有1个染色体和3个质粒;肺炎克雷伯菌KP69和KP19-2029等与本研究菌株染色体基因组相似性大于99.9%,且其各自携带的不同种类的质粒上含有相似的IncR和IncFⅠ耐药基因融合区,bla_(KPC-2)基因位于此融合区中一个由Tn3-△Tn4401-Tn1721/Tn1722序列演化而来的两端插入IS26转座酶基因的结构中;blaNDM-5基因位于一种含有噬菌体插入片段特殊质粒的Ⅰ型转座子上,两端也插入了IS26转座酶基因。结论ST11型肺炎克雷伯菌携带bla_(KPC-2)的IncR和IncFⅡ耐药基因融合区与染色体基因组可能一起广泛存在,特殊质粒携带的blaNDM-5基因可能是通过IS26转座元件介导的基因重组方式偶然获得;携带bla_(KPC-2)基因的ST11型肺炎克雷伯菌在中国广泛传播并能通过IS26转座元件获得其他碳青霉烯酶基因的能力应引起重视。Objective To analyze the characteristics of drug resistance genes in a Klebsiella pneumoniae strain coproducing carbapenemases KPC-2 and NDM-5.Methods Klebsiella pneumoniae KPN-hnqyy was separated from the stool specimen of a patient in the Hematology Department of Affiliated Cancer Hospital of Zhengzhou University.The strain was identified with a BD Phenix-M50 automated microbiology system and the minimum inhibitory concentration against the strain was measured as well.The genotypes of the carbapenemases were tested by enzyme immunochromatographic assay and PCR method.The transferability of related plasmids was analyzed by conjugation test.Whole-genome sequencing of the strain was conducted using PacBio and Illumina platforms.The MLST type,resistance gene and plasmid type of the strain were retrieved in BacWGSTdb.The genome and open reading frame sequence of the strain were compared using Easyfig_2.2.3.Visual cycle graphs were generated using BRIG v0.95.Results Klebsiella pneumoniae KPN-hnqyy was resistant to carbapenem antibiotics.It belonged to ST11 and carried two carbapenemase genes of bla_(KPC-2) and blaNDM-5.The conjugant only harbored the bla_(KPC-2) gene.Whole-genome sequencing revealed that the strain contained one chromosome and three plasmids.Its chromosome genome shared more than 99.9%similarity with that of Klebsiella pneumonia KP69 and KP19-2029.Moreover,a similar IncR and IncFⅠresistance gene fusion region was contained in different types of plasmids carried by them:the bla_(KPC-2) gene was located in a structure—which evolved from the Tn3-△Tn4401-Tn1721/Tn1722 sequence—inside this fusion region with its ends inserted into the transposase IS26 gene;the blaNDM-5 gene was located on a transposon containing the special plasmids of the insertion fragment in phages,with its ends inserted into the transposase IS26 gene too.Conclusions The IncR and IncFⅡresistance gene fusion region of bla_(KPC-2) carried by Klebsiella pneumoniae ST11 might be widely coexistent with the chromosomal genome.The b

关 键 词：肺炎克雷伯菌 KPC-2 NDM-5 Β-内酰胺酶 

分 类 号：R446.5[医药卫生—诊断学]