title: The capsid of the small RNA phage PRR1 is stabilized by metal ions.
abstract: Many nonenveloped virus particles are stabilized by calcium ions bound in the interfaces between the protein subunits. These ions may have a role in the disassembly process. The small RNA phages of the Leviviridae family have T=3 quasi-symmetry and are unique among simple viruses in that they have a coat protein with a translational repressor activity and a fold that has not been observed in other viruses. The crystal structure of phage PRR1 has been determined to 3.5 A resolution. The structure shows a tentative binding site for a calcium ion close to the quasi-3-fold axis. The RNA-binding surface used for repressor activity is mostly conserved. The structure does not show any significant differences between quasi-equivalent subunits, which suggests that the assembly is not controlled by conformational switches as in many other simple viruses.
authors.affiliation: Department of Cell and Molecular Biology, Uppsala University, BMC, Husargatan 3, Box 596, S-751 24 Uppsala, Sweden.
authors.forename: Magnus
authors.initials: M
authors.lastname: Persson
authors.forename: Kaspars
authors.initials: K
authors.lastname: Tars
authors.forename: Lars
authors.initials: L
authors.lastname: Liljas
mesh_terms: D000595:Amino Acid Sequence; D002213:Capsid / Q000737:chemistry / Q000648:ultrastructure*; D036022:Capsid Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D019281:Dimerization; D007477:Ions / Q000737:chemistry*; D008670:Metals / Q000737:chemistry*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D020836:Protein Structure, Quaternary; D012313:RNA / Q000378:metabolism; D012317:RNA Phages / Q000737:chemistry / Q000648:ultrastructure*; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000648:ultrastructure; D016415:Sequence Alignment
chemical_list: D036022:Capsid Proteins; D007477:Ions; D008670:Metals; D011994:Recombinant Proteins; D012313:RNA