title: Structural basis of chaperone function and pilus biogenesis.
abstract: Many Gram-negative pathogens assemble architecturally and functionally diverse adhesive pili on their surfaces by the chaperone-usher pathway. Immunoglobulin-like periplasmic chaperones escort pilus subunits to the usher, a large protein complex that facilitates the translocation and assembly of subunits across the outer membrane. The crystal structure of the PapD-PapK chaperone-subunit complex, determined at 2.4 angstrom resolution, reveals that the chaperone functions by donating its G(1) beta strand to complete the immunoglobulin-like fold of the subunit via a mechanism termed donor strand complementation. The structure of the PapD-PapK complex also suggests that during pilus biogenesis, every subunit completes the immunoglobulin-like fold of its neighboring subunit via a mechanism termed donor strand exchange.
authors.affiliation: Department of Molecular Microbiology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA.
authors.forename: F G
authors.initials: FG
authors.lastname: Sauer
authors.forename: K
authors.initials: K
authors.lastname: Fütterer
authors.forename: J S
authors.initials: JS
authors.lastname: Pinkner
authors.forename: K W
authors.initials: KW
authors.lastname: Dodson
authors.forename: S J
authors.initials: SJ
authors.lastname: Hultgren
authors.forename: G
authors.initials: G
authors.lastname: Waksman
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism*; D018360:Crystallography, X-Ray; D004926:Escherichia coli; D029968:Escherichia coli Proteins; D036781:Fimbriae Proteins; D010861:Fimbriae, Bacterial / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure; D008958:Models, Molecular; D018832:Molecular Chaperones / Q000737:chemistry* / Q000378:metabolism*; D008969:Molecular Sequence Data; D033903:Periplasmic Proteins; D011487:Protein Conformation; D017510:Protein Folding; D017433:Protein Structure, Secondary; D016415:Sequence Alignment
chemical_list: C078802:AtpA protein, E coli; D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D018832:Molecular Chaperones; C084330:PapD protein, E coli; C120849:PapK protein, bacteria; D033903:Periplasmic Proteins; D036781:Fimbriae Proteins