title: Type IV pilin structure and assembly: X-ray and EM analyses of Vibrio cholerae toxin-coregulated pilus and Pseudomonas aeruginosa PAK pilin.
abstract: Pilin assembly into type IV pili is required for virulence by bacterial pathogens that cause diseases such as cholera, pneumonia, gonorrhea, and meningitis. Crystal structures of soluble, N-terminally truncated pilin from Vibrio cholera toxin-coregulated pilus (TCP) and full-length PAK pilin from Pseudomonas aeruginosa reveal a novel TCP fold, yet a shared architecture for the type IV pilins. In each pilin subunit a conserved, extended, N-terminal alpha helix wrapped by beta strands anchors the structurally variable globular head. Inside the assembled pilus, characterized by cryo-electron microscopy and crystallography, the extended hydrophobic alpha helices make multisubunit contacts to provide mechanical strength and flexibility. Outside, distinct interactions of adaptable heads contribute surface variation for specificity of pilus function in antigenicity, motility, adhesion, and colony formation.
authors.affiliation: Department of Molecular Biology and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: Lisa
authors.initials: L
authors.lastname: Craig
authors.forename: Ronald K
authors.initials: RK
authors.lastname: Taylor
authors.forename: Michael E
authors.initials: ME
authors.lastname: Pique
authors.forename: Brian D
authors.initials: BD
authors.lastname: Adair
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Arvai
authors.forename: Mona
authors.initials: M
authors.lastname: Singh
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Lloyd
authors.forename: David S
authors.initials: DS
authors.lastname: Shin
authors.forename: Elizabeth D
authors.initials: ED
authors.lastname: Getzoff
authors.forename: Mark
authors.initials: M
authors.lastname: Yeager
authors.forename: Katrina T
authors.initials: KT
authors.lastname: Forest
authors.forename: John A
authors.initials: JA
authors.lastname: Tainer
mesh_terms: D000595:Amino Acid Sequence / Q000502:physiology; D018360:Crystallography, X-Ray; D036781:Fimbriae Proteins / Q000378:metabolism* / Q000648:ultrastructure; D010861:Fimbriae, Bacterial / Q000378:metabolism* / Q000648:ultrastructure; D008854:Microscopy, Electron; D008958:Models, Molecular; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010446:Peptide Fragments / Q000378:metabolism* / Q000648:ultrastructure; D017510:Protein Folding; D017433:Protein Structure, Secondary / Q000502:physiology; D021122:Protein Subunits / Q000378:metabolism; D011550:Pseudomonas aeruginosa / Q000378:metabolism* / Q000648:ultrastructure; D014734:Vibrio cholerae / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D010446:Peptide Fragments; D021122:Protein Subunits; C085807:TcpA protein, Vibrio cholerae; C432413:type IV pilin (29-150), Pseudomonas aeruginosa, K122-4 strain; D036781:Fimbriae Proteins