title: Molecular characterization of resistance, virulence and clonality in vancomycin-resistant Enterococcus faecium and Enterococcus faecalis: A hospital-based study in Beijing, China.
abstract: The incidence of vancomycin-resistant enterococcus (VRE) in China is increasing, the molecular epidemiology of VRE in China is only partly known. This study was conducted to assess the molecular characterization of resistance, virulence and clonality of 69 vancomycin-resistant Enterococcus faecium (VREfm) and seven vancomycin-resistant Enterococcus faecalis (VREfs) isolates obtained from a Chinese hospital between July 2011 and July 2013. The glycopeptide resistance genes (VanA and VanB) were screened by multiplex PCR. The presence of five putative virulence genes (esp, gelE, asa1, hyl and cylA) were evaluated by another multiplex PCR. Multilocus sequence typing (MLST) scheme was used to assess the clonality. All 76 VRE isolates exhibited VanA phenotype and harbored VanA gene. Esp was the only gene detected both in VREfm and VREfs strains, accounting for 89.9% and 42.9%, respectively. The hyl gene was merely positive in 27.5% of VREfm strains. MLST analysis demonstrated three STs (ST6, ST4 and ST470) in VREfs and twelve STs (ST78, ST571, ST17, ST564, ST389, ST18, ST547, ST341, ST414, ST343, ST262 and ST203) in VREfm, which were all designated as CC17 by eBURST algorithm. An outbreak of VREfm belonging to ST571 was found to happen within the neurology ward in this hospital. To our knowledge, this is the first report of ST6 (CC2) VREfs strains in China and the first outbreak report of VREfm strains belonging to ST571 around the world. Our data could offer important information for understanding the molecular features of VRE in China.
authors.affiliation: Department of Clinical Laboratory, Aerospace Center Hospital, 15 Yuquan Road, Haidian District, 100049 Beijing, China.
authors.forename: Jing-xian
authors.initials: JX
authors.lastname: Yang
authors.affiliation: Department of Microbiology, Peking University Health Science Center, Beijing, China.
authors.forename: Tong
authors.initials: T
authors.lastname: Li
authors.affiliation: Department of Clinical Laboratory, Peking University Third Hospital, Beijing, China.
authors.forename: Yong-zhong
authors.initials: YZ
authors.lastname: Ning
authors.affiliation: Department of Clinical Laboratory, Aerospace Center Hospital, 15 Yuquan Road, Haidian District, 100049 Beijing, China.
authors.forename: Dong-hua
authors.initials: DH
authors.lastname: Shao
authors.affiliation: Department of Clinical Laboratory, Aerospace Center Hospital, 15 Yuquan Road, Haidian District, 100049 Beijing, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Clinical Laboratory, Aerospace Center Hospital, 15 Yuquan Road, Haidian District, 100049 Beijing, China.
authors.forename: Shu-qin
authors.initials: SQ
authors.lastname: Wang
authors.affiliation: Department of Clinical Laboratory, Aerospace Center Hospital, 15 Yuquan Road, Haidian District, 100049 Beijing, China. Electronic address: longforsea@163.com.
authors.forename: Guo-wei
authors.initials: GW
authors.lastname: Liang
mesh_terms: D003428:Cross Infection; D013293:Enterococcus faecalis / Q000145:classification / Q000187:drug effects* / Q000235:genetics* / Q000472:pathogenicity; D016984:Enterococcus faecium / Q000145:classification / Q000187:drug effects* / Q000235:genetics* / Q000472:pathogenicity; D005838:Genotype; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D058885:Multilocus Sequence Typing; D020713:Vancomycin Resistance / Q000235:genetics*; D014774:Virulence / Q000235:genetics*
keywords: Multilocus sequence typing; Vancomycin-resistant enterococcus; Virulence