title: A Comparative Structure/Function Analysis of Two Type IV Pilin DNA Receptors Defines a Novel Mode of DNA Binding.
abstract: DNA transformation is a widespread process allowing bacteria to capture free DNA by using filamentous nano-machines composed of type IV pilins. These proteins can act as DNA receptors as demonstrated by the finding that Neisseria meningitidis ComP minor pilin has intrinsic DNA-binding ability. ComP binds DNA better when it contains the DNA-uptake sequence (DUS) motif abundant in this species genome, playing a role in its trademark ability to selectively take up its own DNA. Here, we report high-resolution structures for meningococcal ComP and Neisseria subflava ComPsub, which recognize different DUS motifs. We show that they are structurally identical type IV pilins that pack readily into filament models and display a unique DD region delimited by two disulfide bonds. Functional analysis of ComPsub defines a new mode of DNA binding involving the DD region, adapted for exported DNA receptors.
authors.affiliation: MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, UK.
authors.forename: Jamie-Lee
authors.initials: JL
authors.lastname: Berry
authors.affiliation: Centre for Structural Biology, Imperial College London, London SW7 2AZ, UK.
authors.forename: Yingqi
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK.
authors.forename: Philip N
authors.initials: PN
authors.lastname: Ward
authors.affiliation: Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Lea
authors.affiliation: Centre for Structural Biology, Imperial College London, London SW7 2AZ, UK. Electronic address: s.j.matthews@imperial.ac.uk.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Matthews
authors.affiliation: MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, UK. Electronic address: v.pelicic@imperial.ac.uk.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Pelicic
mesh_terms: D020816:Amino Acid Motifs; D001665:Binding Sites; D018360:Crystallography, X-Ray; D004269:DNA, Bacterial / Q000378:metabolism*; D036781:Fimbriae Proteins / Q000737:chemistry* / Q000378:metabolism*; D010861:Fimbriae, Bacterial / Q000378:metabolism; D008958:Models, Molecular; D009343:Neisseria / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D011487:Protein Conformation; D017510:Protein Folding
chemical_list: D004269:DNA, Bacterial; D036781:Fimbriae Proteins