title: A type IV pilus mediates DNA binding during natural transformation in Streptococcus pneumoniae.
abstract: Natural genetic transformation is widely distributed in bacteria and generally occurs during a genetically programmed differentiated state called competence. This process promotes genome plasticity and adaptability in Gram-negative and Gram-positive bacteria. Transformation requires the binding and internalization of exogenous DNA, the mechanisms of which are unclear. Here, we report the discovery of a transformation pilus at the surface of competent Streptococcus pneumoniae cells. This Type IV-like pilus, which is primarily composed of the ComGC pilin, is required for transformation. We provide evidence that it directly binds DNA and propose that the transformation pilus is the primary DNA receptor on the bacterial cell during transformation in S. pneumoniae. Being a central component of the transformation apparatus, the transformation pilus enables S. pneumoniae, a major Gram-positive human pathogen, to acquire resistance to antibiotics and to escape vaccines through the binding and incorporation of new genetic material.
authors.affiliation: Institut Pasteur, Groupe Biologie Structurale de la Sécrétion Bactérienne, Paris, France ; CNRS, UMR3528, Paris, France.
authors.forename: Raphaël
authors.initials: R
authors.lastname: Laurenceau
authors.forename: Gérard
authors.initials: G
authors.lastname: Péhau-Arnaudet
authors.forename: Sonia
authors.initials: S
authors.lastname: Baconnais
authors.forename: Joseph
authors.initials: J
authors.lastname: Gault
authors.forename: Christian
authors.initials: C
authors.lastname: Malosse
authors.forename: Annick
authors.initials: A
authors.lastname: Dujeancourt
authors.forename: Nathalie
authors.initials: N
authors.lastname: Campo
authors.forename: Julia
authors.initials: J
authors.lastname: Chamot-Rooke
authors.forename: Eric
authors.initials: E
authors.lastname: Le Cam
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Claverys
authors.forename: Rémi
authors.initials: R
authors.lastname: Fronzes
mesh_terms: D004269:DNA, Bacterial / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D004351:Drug Resistance / Q000502:physiology; D036781:Fimbriae Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D010861:Fimbriae, Bacterial / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D057131:Immune Evasion / Q000502:physiology; D013296:Streptococcus pneumoniae / Q000235:genetics / Q000276:immunology / Q000378:metabolism* / Q000472:pathogenicity; D014169:Transformation, Bacterial / Q000502:physiology*
chemical_list: D004269:DNA, Bacterial; D036781:Fimbriae Proteins