title: Structural insights into serine-rich fimbriae from Gram-positive bacteria.
abstract: The serine-rich repeat family of fimbriae play important roles in the pathogenesis of streptococci and staphylococci. Despite recent attention, their finer structural details and precise adhesion mechanisms have yet to be determined. Fap1 (Fimbriae-associated protein 1) is the major structural subunit of serine-rich repeat fimbriae from Streptococcus parasanguinis and plays an essential role in fimbrial biogenesis, adhesion, and the early stages of dental plaque formation. Combining multidisciplinary, high resolution structural studies with biological assays, we provide new structural insight into adhesion by Fap1. We propose a model in which the serine-rich repeats of Fap1 subunits form an extended structure that projects the N-terminal globular domains away from the bacterial surface for adhesion to the salivary pellicle. We also uncover a novel pH-dependent conformational change that modulates adhesion and likely plays a role in survival in acidic environments.
authors.affiliation: Department of Biological Sciences, Centre for Structural Biology, Imperial College London, South Kensington, London SW7 2AZ, United Kingdom.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Ramboarina
authors.forename: James A
authors.initials: JA
authors.lastname: Garnett
authors.forename: Meixian
authors.initials: M
authors.lastname: Zhou
authors.forename: Yuebin
authors.initials: Y
authors.lastname: Li
authors.forename: Zhixiang
authors.initials: Z
authors.lastname: Peng
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Taylor
authors.forename: Wei-Chao
authors.initials: WC
authors.lastname: Lee
authors.forename: Andrew
authors.initials: A
authors.lastname: Bodey
authors.forename: James W
authors.initials: JW
authors.lastname: Murray
authors.forename: Yilmaz
authors.initials: Y
authors.lastname: Alguel
authors.forename: Julien
authors.initials: J
authors.lastname: Bergeron
authors.forename: Benjamin
authors.initials: B
authors.lastname: Bardiaux
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Sawyer
authors.forename: Rivka
authors.initials: R
authors.lastname: Isaacson
authors.forename: Camille
authors.initials: C
authors.lastname: Tagliaferri
authors.forename: Ernesto
authors.initials: E
authors.lastname: Cota
authors.forename: Michael
authors.initials: M
authors.lastname: Nilges
authors.forename: Peter
authors.initials: P
authors.lastname: Simpson
authors.forename: Teresa
authors.initials: T
authors.lastname: Ruiz
authors.forename: Hui
authors.initials: H
authors.lastname: Wu
authors.forename: Stephen
authors.initials: S
authors.lastname: Matthews
mesh_terms: D000595:Amino Acid Sequence; D001422:Bacterial Adhesion / Q000502:physiology*; D018360:Crystallography, X-Ray; D036781:Fimbriae Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D010861:Fimbriae, Bacterial / Q000737:chemistry / Q000648:ultrastructure*; D006094:Gram-Positive Bacteria / Q000737:chemistry / Q000235:genetics / Q000648:ultrastructure*; D006863:Hydrogen-Ion Concentration; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D019906:Nuclear Magnetic Resonance, Biomolecular; D011487:Protein Conformation; D053838:Scattering, Small Angle; D012694:Serine / Q000235:genetics*; D013291:Streptococcus / Q000737:chemistry* / Q000235:genetics / Q000648:ultrastructure
chemical_list: C403708:fap1 protein, Streptococcus; D036781:Fimbriae Proteins; D012694:Serine