title: Dissemination of NDM-1-Producing Enterobacteriaceae Mediated by the IncX3-Type Plasmid.
abstract: The emergence and spread of NDM-1-producing Enterobacteriaceae have resulted in a worldwide public health risk that has affected some provinces of China. China is an exceptionally large country, and there is a crucial need to investigate the epidemic of blaNDM-1-positive Enterobacteriaceae in our province. A total of 186 carbapenem-resistant Enterobacteriaceae isolates (CRE) were collected in a grade-3 hospital in Zhejiang province. Carbapenem-resistant genes, including blaKPC, blaIMP, blaVIM, blaOXA-48 and blaNDM-1 were screened and sequenced. Ninety isolates were identified as harboring the blaKPC-2 genes, and five blaNDM-1-positive isolates were uncovered. XbaI-PFGE revealed that three blaNDM-1-positive K. pneumoniae isolates belonged to two different clones. S1-PFGE and southern blot suggested that the blaNDM-1 genes were located on IncX3-type plasmids with two different sizes ranging from 33.3 to 54.7 kb (n=4) and 104.5 to 138.9 kb (n=1), respectively, all of which could easily transfer to Escherichia coli by conjugation and electrotransformation. The high-throughput sequencing of two plasmids was performed leading to the identification of a smaller 54-kb plasmid, which had high sequence similarity with a previously reported pCFNDM-CN, and a larger plasmid in which only a 7.8-kb sequence of a common gene environment around blaNDM-1 (blaNDM-1-trpF- dsbC-cutA1-groEL-ΔInsE,) was detected. PCR mapping and sequencing demonstrated that four smaller blaNDM-1 plasmids contained a common gene environment around blaNDM-1 (IS5-blaNDM-1-trpF- dsbC-cutA1-groEL). We monitored the CRE epidemic in our hospital and determined that KPC-2 carbapenemase was a major risk to patient health and the IncX3-type plasmid played a vital role in the spread of the blaNDM-1 gene among the CRE.
authors.affiliation: State Key Laboratory for Diagnosis and Treatment of Infectious diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Department of Infectious Diseases, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Lanfang
authors.initials: L
authors.lastname: Fang
authors.affiliation: Department of Infectious Diseases, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Fu
authors.affiliation: Department of Infectious Diseases, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Xiaoxing
authors.initials: X
authors.lastname: Du
authors.affiliation: State Key Laboratory for Diagnosis and Treatment of Infectious diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Yuqin
authors.initials: Y
authors.lastname: Shen
authors.affiliation: Department of Infectious Diseases, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China; State Key Laboratory for Diagnosis and Treatment of Infectious diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Yunsong
authors.initials: Y
authors.lastname: Yu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015139:Blotting, Southern; D015780:Carbapenems / Q000494:pharmacology; D002681:China / Q000453:epidemiology; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004352:Drug Resistance, Microbial / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D004755:Enterobacteriaceae / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D004756:Enterobacteriaceae Infections / Q000453:epidemiology* / Q000382:microbiology; D005260:Female; D054884:Host-Pathogen Interactions / Q000187:drug effects; D006801:Humans; D007711:Klebsiella pneumoniae / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010957:Plasmids / Q000235:genetics / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D001618:beta-Lactamases / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D015780:Carbapenems; D004269:DNA, Bacterial; C491478:beta-lactamase KPC-2; D001618:beta-Lactamases; C552864:beta-lactamase NDM-1