title: Crystallization and preliminary X-ray diffraction analysis of the Csu pili CsuC-CsuA/B chaperone-major subunit pre-assembly complex from Acinetobacter baumannii.
abstract: The attachment of many Gram-negative pathogens to biotic and abiotic surfaces is mediated by fimbrial adhesins, which are assembled via the classical, alternative and archaic chaperone-usher (CU) pathways. The archaic CU fimbrial adhesins have the widest phylogenetic distribution, yet very little is known about their structure and mechanism of assembly. To elucidate the biogenesis of archaic CU systems, structural analysis of the Csu fimbriae, which are used by Acinetobacter baumannii to form stable biofilms and cause nosocomial infection, was focused on. The major fimbriae subunit CsuA/B complexed with the CsuC chaperone was purified from the periplasm of Escherichia coli cells co-expressing CsuA/B and CsuC, and the complex was crystallized in PEG 3350 solution using the hanging-drop vapour-diffusion method. Selenomethionine-labelled CsuC-CsuA/B complex was purified and crystallized under the same conditions. The crystals diffracted to 2.40 Å resolution and belonged to the hexagonal space group P6(4)22, with unit-cell parameters a = b = 94.71, c = 187.05 Å, α = β = 90, γ = 120°. Initial phases were derived from a single anomalous diffraction (SAD) experiment using the selenomethionine derivative.
authors.affiliation: Department of Chemistry, University of Turku, Joint Biotechnology Laboratory, Arcanum, Vatselankatu 2, 20500 Turku, Finland.
authors.forename: Natalia
authors.initials: N
authors.lastname: Pakharukova
authors.affiliation: Department of Chemistry, University of Turku, Joint Biotechnology Laboratory, Arcanum, Vatselankatu 2, 20500 Turku, Finland.
authors.forename: Minna
authors.initials: M
authors.lastname: Tuittila
authors.affiliation: Department of Chemistry, University of Turku, Joint Biotechnology Laboratory, Arcanum, Vatselankatu 2, 20500 Turku, Finland.
authors.forename: Sari
authors.initials: S
authors.lastname: Paavilainen
authors.affiliation: Department of Chemistry, University of Turku, Joint Biotechnology Laboratory, Arcanum, Vatselankatu 2, 20500 Turku, Finland.
authors.forename: Anton
authors.initials: A
authors.lastname: Zavialov
mesh_terms: D040981:Acinetobacter baumannii / Q000737:chemistry* / Q000378:metabolism; D018829:Adhesins, Bacterial / Q000737:chemistry* / Q000235:genetics; D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D003460:Crystallization; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D010861:Fimbriae, Bacterial / Q000737:chemistry* / Q000235:genetics; D015870:Gene Expression; D008958:Models, Molecular; D018832:Molecular Chaperones / Q000737:chemistry* / Q000235:genetics; D008969:Molecular Sequence Data; D011092:Polyethylene Glycols / Q000737:chemistry; D055503:Protein Multimerization; D021122:Protein Subunits / Q000737:chemistry* / Q000235:genetics; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics; D012645:Selenomethionine / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D018829:Adhesins, Bacterial; D018832:Molecular Chaperones; D021122:Protein Subunits; D011994:Recombinant Proteins; D011092:Polyethylene Glycols; D012645:Selenomethionine; C000595212:polyethylene glycol 3350
keywords: Acinetobacter baumannii; adhesion; archaic; assembly; biofilm; chaperone–usher pathway; fimbriae