title: Enterococcus faecalis Ebp pili are important for cell-cell aggregation and intraspecies gene transfer.
abstract: Enterococcus faecalis is an opportunistic pathogen that ranks among the leading causes of biofilm-associated infections. We previously demonstrated that the endocarditis- and biofilm-associated pili (Ebp) of E. faecalis play a major role in biofilm formation, adherence to abiotic surfaces and experimental infections. In this study, derivatives of E. faecalis strain OG1 were engineered to further characterize functions of Ebp pili. Loss of pili resulted in a 36-fold decrease in the number of closely associated cells when OG1RFΔebpABC was mixed with OG1SSpΔebpABC, compared with mixing the Ebp+ parental strains. In addition, using the Ebp+ parental strains as donor and recipient, we found a statistically significant increase (280-360 %, P < 0.05) in the frequency of plasmid transfer versus using Ebp-  mutants in the conjugation experiments. These results demonstrate a previously unrecognized role of Ebp pili, namely, as important contributors to microscale cell aggregation and horizontal spread of genetic material.
authors.affiliation: Department of Internal Medicine, Division of Infectious Diseases, University of Texas Health Science Center,Houston, Texas,USA.
authors.forename: Sabina Leanti
authors.initials: SL
authors.lastname: La Rosa
authors.affiliation: Department of Internal Medicine, Division of Infectious Diseases, University of Texas Health Science Center,Houston, Texas,USA.|Department of Microbiology and Molecular Genetics, University of Texas Health Science Center,Houston, Texas,USA.
authors.forename: Maria Camila
authors.initials: MC
authors.lastname: Montealegre
authors.affiliation: Department of Internal Medicine, Division of Infectious Diseases, University of Texas Health Science Center,Houston, Texas,USA.|Center for the Study of Emerging and Re-emerging Pathogens, University of Texas Health Science Center,Houston, Texas,USA.
authors.forename: Kavindra V
authors.initials: KV
authors.lastname: Singh
authors.affiliation: Center for the Study of Emerging and Re-emerging Pathogens, University of Texas Health Science Center,Houston, Texas,USA.|Department of Microbiology and Molecular Genetics, University of Texas Health Science Center,Houston, Texas,USA.|Department of Internal Medicine, Division of Infectious Diseases, University of Texas Health Science Center,Houston, Texas,USA.
authors.forename: Barbara E
authors.initials: BE
authors.lastname: Murray
mesh_terms: D001422:Bacterial Adhesion / Q000235:genetics / Q000502:physiology*; D018441:Biofilms / Q000254:growth & development; D003227:Conjugation, Genetic / Q000235:genetics*; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism*; D013293:Enterococcus faecalis / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity*; D010861:Fimbriae, Bacterial / Q000235:genetics*; D022761:Gene Transfer, Horizontal / Q000235:genetics*; D037521:Virulence Factors / Q000235:genetics
chemical_list: D004269:DNA, Bacterial; D037521:Virulence Factors