title: Comparative analysis of the first complete Enterococcus faecium genome.
abstract: Vancomycin-resistant enterococci (VRE) are one of the leading causes of nosocomial infections in health care facilities around the globe. In particular, infections caused by vancomycin-resistant Enterococcus faecium are becoming increasingly common. Comparative and functional genomic studies of E. faecium isolates have so far been limited owing to the lack of a fully assembled E. faecium genome sequence. Here we address this issue and report the complete 3.0-Mb genome sequence of the multilocus sequence type 17 vancomycin-resistant Enterococcus faecium strain Aus0004, isolated from the bloodstream of a patient in Melbourne, Australia, in 1998. The genome comprises a 2.9-Mb circular chromosome and three circular plasmids. The chromosome harbors putative E. faecium virulence factors such as enterococcal surface protein, hemolysin, and collagen-binding adhesin. Aus0004 has a very large accessory genome (38%) that includes three prophage and two genomic islands absent among 22 other E. faecium genomes. One of the prophage was present as inverted 50-kb repeats that appear to have facilitated a 683-kb chromosomal inversion across the replication terminus, resulting in a striking replichore imbalance. Other distinctive features include 76 insertion sequence elements and a single chromosomal copy of Tn1549 containing the vanB vancomycin resistance element. A complete E. faecium genome will be a useful resource to assist our understanding of this emerging nosocomial pathogen.
authors.affiliation: Department of Microbiology and Immunology, University of Melbourne, Victoria, Australia.
authors.forename: Margaret M C
authors.initials: MM
authors.lastname: Lam
authors.forename: Torsten
authors.initials: T
authors.lastname: Seemann
authors.forename: Dieter M
authors.initials: DM
authors.lastname: Bulach
authors.forename: Simon L
authors.initials: SL
authors.lastname: Gladman
authors.forename: Honglei
authors.initials: H
authors.lastname: Chen
authors.forename: Volker
authors.initials: V
authors.lastname: Haring
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Moore
authors.forename: Susan
authors.initials: S
authors.lastname: Ballard
authors.forename: M Lindsay
authors.initials: ML
authors.lastname: Grayson
authors.forename: Paul D R
authors.initials: PD
authors.lastname: Johnson
authors.forename: Benjamin P
authors.initials: BP
authors.lastname: Howden
authors.forename: Timothy P
authors.initials: TP
authors.lastname: Stinear
mesh_terms: D002876:Chromosomes, Bacterial; D016984:Enterococcus faecium / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism* / Q000472:pathogenicity; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D016680:Genome, Bacterial / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D010957:Plasmids; D039002:Prophages / Q000235:genetics; D014640:Vancomycin / Q000494:pharmacology; D020713:Vancomycin Resistance; D014774:Virulence
chemical_list: D014640:Vancomycin