title: IS256 abolishes gelatinase activity and biofilm formation in a mutant of the nosocomial pathogen Enterococcus faecalis V583.
abstract: Enterococcus faecalis is one of the most controversial species of lactic acid bacteria. Some strains are used as probiotics, while others are associated with severe and life-threatening nosocomial infections. Their pathogenicity depends on the acquisition of multidrug resistance and virulence factors. Gelatinase, which is required in the first steps of biofilm formation, is an important virulence determinant involved in E. faecalis pathogenesis, including endocarditis and peritonitis. The gene that codes for gelatinase (gelE) is controlled by the Fsr quorum-sensing system, whose encoding genes (fsrA, fsrB, fsrC, and fsrD) are located immediately upstream of gelE. The integration of a DNA fragment into the fsr locus of a derived mutant of E. faecalis V583 suppressed the gelatinase activity and prevented biofilm formation. Sequence analysis indicated the presence of IS256 integrated into the fsrC gene at nucleotide position 321. Interestingly, IS256 is also associated with biofilm formation in Staphylococcus epidermidis and Staphylococcus aureus. This is the first description of an insertion sequence that prevents biofilm formation in E. faecalis.
authors.affiliation: Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300 Villaviciosa, Asturias, Spain.|Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300 Villaviciosa, Asturias, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Perez
authors.affiliation: Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300 Villaviciosa, Asturias, Spain.|Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300 Villaviciosa, Asturias, Spain.
authors.forename: Marina
authors.initials: M
authors.lastname: Calles-Enríquez
authors.affiliation: Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300 Villaviciosa, Asturias, Spain.|Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300 Villaviciosa, Asturias, Spain.
authors.forename: Beatriz
authors.initials: B
authors.lastname: del Rio
authors.affiliation: Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300 Villaviciosa, Asturias, Spain.|Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300 Villaviciosa, Asturias, Spain.
authors.forename: Victor
authors.initials: V
authors.lastname: Ladero
authors.affiliation: Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300 Villaviciosa, Asturias, Spain.|Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300 Villaviciosa, Asturias, Spain.
authors.forename: María Cruz
authors.initials: MC
authors.lastname: Martín
authors.affiliation: Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300 Villaviciosa, Asturias, Spain.|Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300 Villaviciosa, Asturias, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Fernández
authors.affiliation: Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300 Villaviciosa, Asturias, Spain.|Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n, 33300 Villaviciosa, Asturias, Spain.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Alvarez
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D018441:Biofilms; D003428:Cross Infection / Q000382:microbiology*; D004251:DNA Transposable Elements; D013293:Enterococcus faecalis / Q000201:enzymology* / Q000235:genetics / Q000502:physiology*; D018093:Gelatinases / Q000235:genetics / Q000378:metabolism*; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology*; D006801:Humans; D016254:Mutagenesis, Insertional; D053038:Quorum Sensing
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D018093:Gelatinases
keywords: Enterococcus faecalis; biofilm; gelatinase; gélatinase; insertion sequence; séquence d’insertion