1ijs
CPV (STRAIN D) mutant A300D, complex (VIRAL COAT/DNA), VP2, PH=7.5, T=4 DEGREES C
Structural highlights
FunctionCAPSD_PAVCD Capsid protein self-assembles to form an icosahedral capsid with a T=1 symmetry, about 22 nm in diameter, and consisting of 60 copies of two size variants of the capsid proteins, VP1 and VP2, which differ by the presence of an N-terminal extension in the minor protein VP1. The capsid encapsulates the genomic ssDNA. Capsid proteins are responsible for the attachment to host cell receptor TFRC. This attachment induces virion internalization predominantly through clathrin-endocytosis. Binding to the host receptors also induces capsid rearrangements leading to surface exposure of VP1 N-terminus, specifically its phospholipase A2-like region and nuclear localization signal(s). VP1 N-terminus might serve as a lipolytic enzyme to breach the endosomal membrane during entry into host cell (By similarity). Intracytoplasmic transport involves microtubules and interaction between capsid proteins and host dynein. Exposure of nuclear localization signal probably allows nuclear import of capsids.[1] [2] [3] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedA single mutation in canine parvovirus (CPV) of VP2 residue 300 from alanine to aspartic acid causes a loss of canine host range and alters the antigenic properties of the virus. The three-dimensional structure of this mutant has been solved to 3.25 A resolution. Crystals of full particles were triclinic, with cell dimensions of a = 267.6, b = 268.5, c = 274.3 A. alpha = 61.9, beta = 62.6, and gamma = 60.2 degrees. The native structure of CPV was used as an initial model. Phases were improved by real-space electron density averaging. In spite of the relative low percentage of observed reflections (32.5% of the data between 15.0 and 3.25 A resolution), the presence of 60-fold noncrystallographic redundancy allowed the averaging procedure to converge smoothly. The mutant aspartic acid at residue 300 forms a salt bridge with Arg81 in an icosahedrally threefold-related subunit, inducing local changes within the antigenic site B on the CPV surface. In addition, the loop between residues 359 and 374 adopts a conformation similar to that displayed by feline panleukopenia virus. The ability of the Ala300-->Asp mutant to evade antibody binding can be associated with the change of charge distribution and structure in the antigenic binding site. The variation in host range behavior may be due to the increased stability as a result of formation of the salt bridge between adjacent subunits. Structural analysis of a mutation in canine parvovirus which controls antigenicity and host range.,Llamas-Saiz AL, Agbandje-McKenna M, Parker JS, Wahid AT, Parrish CR, Rossmann MG Virology. 1996 Nov 1;225(1):65-71. PMID:8918534[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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