NDM-1-producing Enterobacteriaceae in a teaching hospital in Shanghai, China: IncX3-type plasmids may contribute to the dissemination of blaNDM-1.
OBJECTIVE
To provide the epidemiological dissemination and the genetic characteristics of bla(NDM-1) in a teaching hospital in Shanghai, China.


METHODS
Here, the carbapenemase genes of 114 CRE isolates were evaluated by polymerase chain reaction (PCR). Clonal relatedness was assessed by pulsed-field gel electrophoresis (PFGE). Conjugation experiments and Southern blot hybridization were performed to determine the transferability of plasmids. Then plasmids were completely sequenced by the shotgun method.


RESULTS
Two Klebsiella pneumoniae strains (RJA1227 and RJF866) and one Raoultella planticola strain (RJA274) were identified as NDM-1 positive. The two K. pneumoniae isolates belonged to ST11 and exhibited highly similar PFGE patterns. Shotgun sequencing showed that plasmid pRJF866 (ca. 110 kb) contained genes associated with the IncFII-FIB group and was highly similar to plasmid pKOX_NDM1. RJA274 (ca. 50 kb) harbored bla(NDM-1) on an IncX3 plasmid, which was nearly identical to plasmid pNDM-HN380 except that part of the ISAba125 element is missing.


CONCLUSIONS
This is the first report of NDM-1-positive Enterobacteriaceae from Shanghai, China. IncX3 plasmids, reported in various species in the United Arab Emirates and China, may contribute to the dissemination of bla(NDM-1.). More attention should be devoted to monitoring the dissemination of the NDM-1 gene due to its potential horizontal transfer via mobile genetic elements.
Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No.197 Ruijin ER Road, Shanghai 200025, China.
Hongping
H
Qu
Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No.197 Ruijin ER Road, Shanghai 200025, China.
Xiaoli
X
Wang
Department of Clinical Microbiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No.197 Ruijin ER Road, Shanghai 200025, China.
Yuxing
Y
Ni
Department of Pulmonary Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No.197 Ruijin ER Road, Shanghai 200025, China.
Jialin
J
Liu
Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No.197 Ruijin ER Road, Shanghai 200025, China.
Ruoming
R
Tan
Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No.197 Ruijin ER Road, Shanghai 200025, China.
Jie
J
Huang
Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No.197 Ruijin ER Road, Shanghai 200025, China. Electronic address: Lileiys1023@yeah.net.
Lei
L
Li
Department of Clinical Microbiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No.197 Ruijin ER Road, Shanghai 200025, China. Electronic address: 13671578899@126.com.
Jingyong
J
Sun
D001426:Bacterial Proteins / Q000235:genetics*; D002681:China / Q000453:epidemiology; D003227:Conjugation, Genetic; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology; D016521:Electrophoresis, Gel, Pulsed-Field; D004755:Enterobacteriaceae / Q000235:genetics* / Q000302:isolation & purification; D004756:Enterobacteriaceae Infections / Q000453:epidemiology*; D023061:Gene Order; D006784:Hospitals, Teaching; D006801:Humans; D007710:Klebsiella Infections / Q000453:epidemiology* / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000235:genetics* / Q000302:isolation & purification; D008297:Male; D010957:Plasmids / Q000235:genetics / Q000302:isolation & purification; D014479:United Arab Emirates; D055815:Young Adult; D001618:beta-Lactamases / Q000235:genetics*
D001426:Bacterial Proteins; D001618:beta-Lactamases; C552864:beta-lactamase NDM-1; C063912:carbapenemase
Carbapenem-resistant Enterobacteriaceae; Dissemination; NDM-1; Plasmid