title: Antigen I/II encoded by integrative and conjugative elements of Streptococcus agalactiae and role in biofilm formation.
abstract: Streptococcus agalactiae (i.e. Group B streptococcus, GBS) is a major human and animal pathogen. Genes encoding putative surface proteins and in particular an antigen I/II have been identified on Integrative and Conjugative Elements (ICEs) found in GBS. Antigens I/II are multimodal adhesins promoting colonization of the oral cavity by streptococci such as Streptococcus gordonii and Streptococcus mutans. The prevalence and diversity of antigens I/II in GBS were studied by a bioinformatic analysis. It revealed that antigens I/II, which are acquired by horizontal transfer via ICEs, exhibit diversity and are widespread in GBS, in particular in the serotype Ia/ST23 invasive strains. This study aimed at characterizing the impact on GBS biology of proteins encoded by a previously characterized ICE of S. agalactiae (ICE_515_tRNA(Lys)). The production and surface exposition of the antigen I/II encoded by this ICE was examined using RT-PCR and immunoblotting experiments. Surface proteins of ICE_515_tRNA(Lys) were found to contribute to GBS biofilm formation and to fibrinogen binding. Contribution of antigen I/II encoded by SAL_2056 to biofilm formation was also demonstrated. These results highlight the potential for ICEs to spread microbial adhesins between species.
authors.affiliation: INRA, UMR1128 DynAMic, F-54506 Vandoeuvre-lès-Nancy, France; Université de Lorraine, UMR1128 DynAMic, F-54506 Vandoeuvre-lès-Nancy, France; ANSES Site de Lyon, Unité Antibiorésistance et Virulence Bactériennes, Lyon, France.
authors.forename: Sarah
authors.initials: S
authors.lastname: Chuzeville
authors.affiliation: Institut Pasteur, Unité de Biologie des Bactéries Pathogènes à Gram-Positif, Paris, France; CNRS ERL3526, Paris, France.
authors.forename: Shaynoor
authors.initials: S
authors.lastname: Dramsi
authors.affiliation: ANSES Site de Lyon, Unité Antibiorésistance et Virulence Bactériennes, Lyon, France.
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Madec
authors.affiliation: ANSES Site de Lyon, Unité Antibiorésistance et Virulence Bactériennes, Lyon, France.
authors.forename: Marisa
authors.initials: M
authors.lastname: Haenni
authors.affiliation: INRA, UMR1128 DynAMic, F-54506 Vandoeuvre-lès-Nancy, France; Université de Lorraine, UMR1128 DynAMic, F-54506 Vandoeuvre-lès-Nancy, France. Electronic address: sophie.payot@nancy.inra.fr.
authors.forename: Sophie
authors.initials: S
authors.lastname: Payot
mesh_terms: D018829:Adhesins, Bacterial / Q000145:classification / Q000235:genetics*; D000942:Antigens, Bacterial / Q000145:classification / Q000235:genetics*; D018441:Biofilms / Q000254:growth & development*; D014644:Genetic Variation; D015151:Immunoblotting; D020071:Interspersed Repetitive Sequences; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013292:Streptococcus agalactiae / Q000235:genetics* / Q000502:physiology*
chemical_list: D018829:Adhesins, Bacterial; D000942:Antigens, Bacterial
keywords: Adhesion; Antigen I/II; Biofilm; Fibrinogen; GBS; ICE