title: A Distinct Type of Pilus from the Human Microbiome.
abstract: Pili are proteinaceous polymers of linked pilins that protrude from the cell surface of many bacteria and often mediate adherence and virulence. We investigated a set of 20 Bacteroidia pilins from the human microbiome whose structures and mechanism of assembly were unknown. Crystal structures and biochemical data revealed a diverse protein superfamily with a common Greek-key β sandwich fold with two transthyretin-like repeats that polymerize into a pilus through a strand-exchange mechanism. The assembly mechanism of the central, structural pilins involves proteinase-assisted removal of their N-terminal β strand, creating an extended hydrophobic groove that binds the C-terminal donor strands of the incoming pilin. Accessory pilins at the tip and base have unique structural features specific to their location, allowing initiation or termination of the assembly. The Bacteroidia pilus, therefore, has a biogenesis mechanism that is distinct from other known pili and likely represents a different type of bacterial pilus.
authors.affiliation: Joint Center for Structural Genomics, http://www.jcsg.org; SLAC National Accelerator Laboratory, Stanford Synchrotron Radiation Lightsource, Menlo Park, CA 94025, USA.
authors.forename: Qingping
authors.initials: Q
authors.lastname: Xu
authors.affiliation: Division of Microbiology and Oral Infection, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan.
authors.forename: Mikio
authors.initials: M
authors.lastname: Shoji
authors.affiliation: Division of Microbiology and Oral Infection, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Shibata
authors.affiliation: Division of Microbiology and Oral Infection, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan.
authors.forename: Mariko
authors.initials: M
authors.lastname: Naito
authors.affiliation: Division of Microbiology and Oral Infection, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Sato
authors.affiliation: Joint Center for Structural Genomics, http://www.jcsg.org; Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: Marc-André
authors.initials: MA
authors.lastname: Elsliger
authors.affiliation: Joint Center for Structural Genomics, http://www.jcsg.org; Protein Sciences Department, Genomics Institute of the Novartis Research Foundation, San Diego, CA 92121, USA.
authors.forename: Joanna C
authors.initials: JC
authors.lastname: Grant
authors.affiliation: Joint Center for Structural Genomics, http://www.jcsg.org; SLAC National Accelerator Laboratory, Stanford Synchrotron Radiation Lightsource, Menlo Park, CA 94025, USA.
authors.forename: Herbert L
authors.initials: HL
authors.lastname: Axelrod
authors.affiliation: Joint Center for Structural Genomics, http://www.jcsg.org; SLAC National Accelerator Laboratory, Stanford Synchrotron Radiation Lightsource, Menlo Park, CA 94025, USA.
authors.forename: Hsiu-Ju
authors.initials: HJ
authors.lastname: Chiu
authors.affiliation: Joint Center for Structural Genomics, http://www.jcsg.org; Protein Sciences Department, Genomics Institute of the Novartis Research Foundation, San Diego, CA 92121, USA.
authors.forename: Carol L
authors.initials: CL
authors.lastname: Farr
authors.affiliation: Joint Center for Structural Genomics, http://www.jcsg.org; Center for Research in Biological Systems, University of California, San Diego, La Jolla, CA 92093, USA; Program on Bioinformatics and Systems Biology, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA.
authors.forename: Lukasz
authors.initials: L
authors.lastname: Jaroszewski
authors.affiliation: Joint Center for Structural Genomics, http://www.jcsg.org; Protein Sciences Department, Genomics Institute of the Novartis Research Foundation, San Diego, CA 92121, USA.
authors.forename: Mark W
authors.initials: MW
authors.lastname: Knuth
authors.affiliation: Joint Center for Structural Genomics, http://www.jcsg.org; SLAC National Accelerator Laboratory, Stanford Synchrotron Radiation Lightsource, Menlo Park, CA 94025, USA.
authors.forename: Ashley M
authors.initials: AM
authors.lastname: Deacon
authors.affiliation: Joint Center for Structural Genomics, http://www.jcsg.org; Center for Research in Biological Systems, University of California, San Diego, La Jolla, CA 92093, USA; Program on Bioinformatics and Systems Biology, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA.
authors.forename: Adam
authors.initials: A
authors.lastname: Godzik
authors.affiliation: Joint Center for Structural Genomics, http://www.jcsg.org; Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA; Protein Sciences Department, Genomics Institute of the Novartis Research Foundation, San Diego, CA 92121, USA.
authors.forename: Scott A
authors.initials: SA
authors.lastname: Lesley
authors.affiliation: Centre for Immunology and Infectious Disease (CIID), Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, 4 Newark Street, London E1 2AT, UK.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Curtis
authors.affiliation: Division of Microbiology and Oral Infection, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan. Electronic address: knak@nagasaki-u.ac.jp.
authors.forename: Koji
authors.initials: K
authors.lastname: Nakayama
authors.affiliation: Joint Center for Structural Genomics, http://www.jcsg.org; Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA. Electronic address: wilson@scripps.edu.
authors.forename: Ian A
authors.initials: IA
authors.lastname: Wilson
mesh_terms: D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray; D036781:Fimbriae Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D010861:Fimbriae, Bacterial; D000069196:Gastrointestinal Microbiome; D006801:Humans; D008074:Lipoproteins / Q000737:chemistry / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016415:Sequence Alignment
chemical_list: D008074:Lipoproteins; D036781:Fimbriae Proteins