title: Atomic resolution insights into curli fiber biogenesis.
abstract: Bacteria produce functional amyloid fibers called curli in a controlled, noncytotoxic manner. These extracellular fimbriae enable biofilm formation and promote pathogenicity. Understanding curli biogenesis is important for appreciating microbial lifestyles and will offer clues as to how disease-associated human amyloid formation might be ameliorated. Proteins encoded by the curli specific genes (csgA-G) are required for curli production. We have determined the structure of CsgC and derived the first structural model of the outer-membrane subunit translocator CsgG. Unexpectedly, CsgC is related to the N-terminal domain of DsbD, both in structure and oxido-reductase capability. Furthermore, we show that CsgG belongs to the nascent class of helical outer-membrane macromolecular exporters. A cysteine in a CsgG transmembrane helix is a potential target of CsgC, and mutation of this residue influences curli assembly. Our study provides the first high-resolution structural insights into curli biogenesis.
authors: Division of Molecular Biosciences, Faculty of Natural Sciences, Imperial College London, London, SW7 2AZ, UK.
authors: Jonathan D
authors: JD
authors: Taylor
authors: Yizhou
authors: Y
authors: Zhou
authors: Paula S
authors: PS
authors: Salgado
authors: Ardan
authors: A
authors: Patwardhan
authors: Matt
authors: M
authors: McGuffie
authors: Tillmann
authors: T
authors: Pape
authors: Grzegorz
authors: G
authors: Grabe
authors: Elisabeth
authors: E
authors: Ashman
authors: Sean C
authors: SC
authors: Constable
authors: Peter J
authors: PJ
authors: Simpson
authors: Wei-chao
authors: WC
authors: Lee
authors: Ernesto
authors: E
authors: Cota
authors: Matthew R
authors: MR
authors: Chapman
authors: Steve J
authors: SJ
authors: Matthews
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D018441:Biofilms; D018360:Crystallography, X-Ray; D019453:Escherichia coli O157 / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D010861:Fimbriae, Bacterial / Q000737:chemistry* / Q000378:metabolism; D008074:Lipoproteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D008854:Microscopy, Electron; D008958:Models, Molecular; D008969:Molecular Sequence Data; D046912:Multiprotein Complexes / Q000737:chemistry / Q000378:metabolism; D016297:Mutagenesis, Site-Directed; D020125:Mutation, Missense; D010084:Oxidation-Reduction; D055503:Protein Multimerization; D017434:Protein Structure, Tertiary
chemical_list: C556817:CsgC protein, E coli; C534546:CsgG protein, E coli; D029968:Escherichia coli Proteins; D008074:Lipoproteins; D046912:Multiprotein Complexes