title: Structure of AP205 Coat Protein Reveals Circular Permutation in ssRNA Bacteriophages.
abstract: AP205 is a single-stranded RNA bacteriophage that has a coat protein sequence not similar to any other known single-stranded RNA phage. Here, we report an atomic-resolution model of the AP205 virus-like particle based on a crystal structure of an unassembled coat protein dimer and a cryo-electron microscopy reconstruction of the assembled particle, together with secondary structure information from site-specific solid-state NMR data. The AP205 coat protein dimer adopts the conserved Leviviridae coat protein fold except for the N-terminal region, which forms a beta-hairpin in the other known single-stranded RNA phages. AP205 has a similar structure at the same location formed by N- and C-terminal beta-strands, making it a circular permutant compared to the other coat proteins. The permutation moves the coat protein termini to the most surface-exposed part of the assembled particle, which explains its increased tolerance to long N- and C-terminal fusions.
authors: Latvian Biomedical Research and Study Center, Rātsupītes 1, LV1067 Riga, Latvia.
authors: Mihails
authors: M
authors: Shishovs
authors: Latvian Biomedical Research and Study Center, Rātsupītes 1, LV1067 Riga, Latvia.
authors: Janis
authors: J
authors: Rumnieks
authors: Netherlands Centre for Electron Nanoscopy, Institute of Biology Leiden, Leiden University Einsteinweg 55, 2333 CC Leiden, The Netherlands.
authors: Christoph
authors: C
authors: Diebolder
authors: Université de Lyon, Centre de RMN à Très Hauts Champs, Institut des Sciences Analytiques (UMR 5280 - CNRS, ENS Lyon, UCB Lyon 1), 69100 Villeurbanne, France.
authors: Kristaps
authors: K
authors: Jaudzems
authors: Université de Lyon, Centre de RMN à Très Hauts Champs, Institut des Sciences Analytiques (UMR 5280 - CNRS, ENS Lyon, UCB Lyon 1), 69100 Villeurbanne, France.
authors: Loren B
authors: LB
authors: Andreas
authors: Université de Lyon, Centre de RMN à Très Hauts Champs, Institut des Sciences Analytiques (UMR 5280 - CNRS, ENS Lyon, UCB Lyon 1), 69100 Villeurbanne, France.
authors: Jan
authors: J
authors: Stanek
authors: Latvian Biomedical Research and Study Center, Rātsupītes 1, LV1067 Riga, Latvia.
authors: Andris
authors: A
authors: Kazaks
authors: Latvian Biomedical Research and Study Center, Rātsupītes 1, LV1067 Riga, Latvia.
authors: Svetlana
authors: S
authors: Kotelovica
authors: Latvian Biomedical Research and Study Center, Rātsupītes 1, LV1067 Riga, Latvia.
authors: Inara
authors: I
authors: Akopjana
authors: Université de Lyon, Centre de RMN à Très Hauts Champs, Institut des Sciences Analytiques (UMR 5280 - CNRS, ENS Lyon, UCB Lyon 1), 69100 Villeurbanne, France.
authors: Guido
authors: G
authors: Pintacuda
authors: Netherlands Centre for Electron Nanoscopy, Institute of Biology Leiden, Leiden University Einsteinweg 55, 2333 CC Leiden, The Netherlands; Department of Cell Biology, Leiden University Medical Center, Postal Zone S1-P, P.O.Box 9600, 2300 RC Leiden, The Netherlands.
authors: Roman I
authors: RI
authors: Koning
authors: Latvian Biomedical Research and Study Center, Rātsupītes 1, LV1067 Riga, Latvia; Faculty of Biology, Department of Molecular Biology, University of Latvia, Jelgavas 1, LV-1004 Riga, Latvia. Electronic address: kaspars@biomed.lu.lv.
authors: Kaspars
authors: K
authors: Tars
mesh_terms: D001435:Bacteriophages / Q000737:chemistry*; D036022:Capsid Proteins / Q000737:chemistry* / Q000235:genetics*; D020285:Cryoelectron Microscopy; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D011487:Protein Conformation; D012328:RNA Viruses / Q000737:chemistry*
chemical_list: D036022:Capsid Proteins
keywords: Leviviridae; RNA bacteriophage; circular permutation; coat protein; virus-like particle