title: Multilocus sequence typing scheme for Enterococcus faecalis reveals hospital-adapted genetic complexes in a background of high rates of recombination.
abstract: A multilocus sequence typing (MLST) scheme based on seven housekeeping genes was used to investigate the epidemiology and population structure of Enterococcus faecalis. MLST of 110 isolates from different sources and geographic locations revealed 55 different sequence types that grouped into four major clonal complexes (CC2, CC9, CC10, and CC21) by use of eBURST. Two of these clonal complexes, CC2 and CC9, are particularly fit in the hospital environment, as CC2 includes the previously described BVE clonal complex identified by an alternative MLST scheme and CC9 includes exclusively isolates from hospitalized patients. Identical alleles were found in genetically diverse isolates with no linkage disequilibrium, while the different MLST loci gave incongruent phylogenetic trees. This demonstrates that recombination is an important mechanism driving genetic variation in E. faecalis and suggests an epidemic population structure for E. faecalis. Our novel MLST scheme provides an excellent tool for investigating local and short-term epidemiology as well as global epidemiology, population structure, and genetic evolution of E. faecalis.
authors.affiliation: Servicio de Microbiología, Hospital Universitario Ramón y Cajal, Madrid, Spain. pruizg.hrc@salud.madrid.org
authors.forename: Patricia
authors.initials: P
authors.lastname: Ruiz-Garbajosa
authors.forename: Marc J M
authors.initials: MJ
authors.lastname: Bonten
authors.forename: D Ashley
authors.initials: DA
authors.lastname: Robinson
authors.forename: Janetta
authors.initials: J
authors.lastname: Top
authors.forename: Sreedhar R
authors.initials: SR
authors.lastname: Nallapareddy
authors.forename: Carmen
authors.initials: C
authors.lastname: Torres
authors.forename: Teresa M
authors.initials: TM
authors.lastname: Coque
authors.forename: Rafael
authors.initials: R
authors.lastname: Cantón
authors.forename: Fernando
authors.initials: F
authors.lastname: Baquero
authors.forename: Barbara E
authors.initials: BE
authors.lastname: Murray
authors.forename: Rosa
authors.initials: R
authors.lastname: del Campo
authors.forename: Rob J L
authors.initials: RJ
authors.lastname: Willems
mesh_terms: D000483:Alleles; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics*; D015373:Bacterial Typing Techniques; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology; D004269:DNA, Bacterial / Q000032:analysis; D013293:Enterococcus faecalis / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D016908:Gram-Positive Bacterial Infections / Q000453:epidemiology / Q000382:microbiology; D006801:Humans; D011995:Recombination, Genetic; D017422:Sequence Analysis, DNA
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial