title: Assembly of bacteriophage PRD1 spike complex: role of the multidomain protein P5.
abstract: The spike structure of bacteriophage PRD1 is comprised of proteins P2, P5, and P31. It resembles the corresponding receptor-binding structure of adenoviruses. We show that purified recombinant protein P5 is an elongated (30 x 2.7 nm; R(h) = 5.5 nm), multidomain trimer which can slowly associate into nonamers. Cleavage of the 340 amino acid long P5 with collagenase yields 2 fragments. The larger, 205 amino acid long C-terminal fragment appears to contain the residues responsible for the trimerization of the protein, whereas the smaller N-terminal part mediates the interaction of P5 with the pentameric vertex protein P31 (24 x 2.5 nm, R(h) = 4.2 nm). In addition, the presence of the N-terminal sequence is required for the formation of the P5 nonamer. The results presented here suggest that P5 and P31 form an elongated adaptor complex at the 5-fold vertexes of the virion which anchors the adsorption protein P2 (21 x 2.5 nm; R(h) = 4.1 nm). Our results also suggest that the P5 trimer forms a substantial part of the viral spike shaft that was previously thought to be composed exclusively of protein P2.
authors.affiliation: Institute of Biotechnology and Department of Biosciences, Viikki Biocenter, P.O. Box 56 (Viikinkaari 5), 00014 University of Helsinki, Finland. javier.caldentey@helsinki.fi
authors.forename: J
authors.initials: J
authors.lastname: Caldentey
authors.forename: R
authors.initials: R
authors.lastname: Tuma
authors.forename: D H
authors.initials: DH
authors.lastname: Bamford
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D003094:Collagen / Q000737:chemistry / Q000235:genetics; D007700:Kinetics; D046911:Macromolecular Substances; D008958:Models, Molecular; D008969:Molecular Sequence Data; D020836:Protein Structure, Quaternary; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D017916:Tectiviridae / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D014764:Viral Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
chemical_list: D046911:Macromolecular Substances; D011994:Recombinant Proteins; D014764:Viral Proteins; D003094:Collagen