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Bernard Delmas - One of the best experts on this subject based on the ideXlab platform.

  • Genome and polypeptides characterization of Tellina Virus 1 reveals a fifth genetic cluster in the Birnaviridae family
    Virology, 2008
    Co-Authors: Isabelle Nobiron, Bruno Costa, Celine Henry, Pierre Boudinot, Marie Galloux, Corinne Torhy, Nathalie Lejal, Bernard Delmas
    Abstract:

    We characterized tellina Virus 1 (TV-1), a birnaVirus isolated from the marine bivalve mollusk Tellina tenuis. Genome sequence analysis established that TV-1 is representative of a viral cluster distant from other birnaViruses. The maturation process of the polyprotein encoded by the genomic segment A was delineated with the identification of the N-termini of the viral protease VP4 and the ribonucleoprotein VP3, and the characterization of peptides deriving from the processing of pVP2, the VP2 capsid protein precursor. One of these peptides was shown to possess a membrane-disrupting domain. Like the blotched Snakehead Virus, the polyprotein exhibits a non-structural polypeptide (named [X]) located between pVP2 and VP4. Mutagenesis analysis allowed the identification in VP4 of a catalytic Ser-Lys dyad that does not possess the common Gly-X-Ser signature of the serine hydrolases. The genomic segment B encodes the viral RNA-dependent RNA-polymerase VP1 with the unique sequence motif arrangement identified in other birnaVirus VP1s.

  • Crystal structure of the VP4 protease from infectious pancreatic necrosis Virus reveals the acyl-enzyme complex for an intermolecular self-cleavage reaction
    Journal of Biological Chemistry, 2007
    Co-Authors: Jaeyong Lee, Bernard Delmas, Anat R Feldman, Mark Paetzel
    Abstract:

    Infectious pancreatic necrosis Virus (IPNV), an aquatic birnaVirus that infects salmonid fish, encodes a large polyprotein (NH2-pVP2-VP4-VP3-COOH) that is processed through the proteolytic activity of its own protease, VP4, to release the proteins pVP2 and VP3. pVP2 is further processed to give rise to the capsid protein VP2 and three peptides that are incorporated into the virion. Reported here are two crystal structures of the IPNV VP4 protease solved from two different crystal symmetries. The electron density at the active site in the triclinic crystal form, refined to 2.2-A˚ resolution, reveals the acyl-enzyme complex formed with an internalVP4cleavage site. The complex was generated using a truncated enzyme in which the general base lysine was substituted. Inside the complex, the nucleophilic Ser633O_ forms an ester bond with the main-chain carbonyl of the C-terminal residue, Ala716, of a neighboring VP4. The structure of this substrate-VP4 complex allows us to identify the S1, S3, S5, and S6 substrate binding pockets as well as other substrate- VP4 interactions and therefore provides structural insights into the substrate specificity of this enzyme. The structure from the hexagonal crystal form, refined to 2.3-A˚ resolution, reveals the free-binding site of the protease. Three-dimensional alignment with the VP4 of blotched Snakehead Virus, another birnaVirus, shows that the overall structure of VP4 is conserved despite a low level of sequence identity (_19%). The structure determinations of IPNV VP4, the first of an acyl-enzyme complex for a Ser/Lys dyad protease, provide insights into the catalytic mechanism and substrate recognition of this type of protease.

  • Expression, purification and crystallization of a birnaVirus-encoded protease, VP4, from blotched Snakehead Virus (BSNV)
    Acta Crystallographica Section F: Structural Biology and Crystallization Communications, 2006
    Co-Authors: Jaeyong Lee, Bernard Delmas, Anat R Feldman, Mark Paetzel
    Abstract:

    Blotched Snakehead Virus (BSNV) is a member of the Birnaviridae family that requires a virally encoded protease known as VP4 in order to process its polyprotein into viral capsid protein precursors (pVP2 and VP3). VP4 belongs to a family of serine proteases that utilize a serine/lysine catalytic dyad mechanism. A mutant construct of VP4 with a short C-terminal truncation was overexpressed in Escherichia coli and purified to homogeneity for crystallization. Using the sitting-drop vapour-diffusion method at room temperature, protein crystals with two distinct morphologies were observed. Cubic crystals grown in PEG 2000 MME and magnesium acetate at pH 8.5 belong to space group I23, with unit-cell parameters a = b = c = 143.8 A ° . Trigonal crystals grown in ammonium sulfate and glycerol at pH 8.5 belong to space group P321/P312, with unit-cell parameters a = b = 158.2, c = 126.4 A ° .

  • blotched Snakehead Virus is a new aquatic birnaVirus that is slightly more related to avibirnaVirus than to aquabirnaVirus
    Journal of Virology, 2003
    Co-Authors: Bruno Costa, Stephanie Soignier, Corinne Thory, Jeanclaude Huet, Christophe Chevalier, Celine Henry, Bernard Delmas
    Abstract:

    By different approaches, we characterized the birnaVirus blotched Snakehead Virus (BSNV). The sequence of genomic segment A revealed the presence of two open reading frames (ORFs): a large ORF with a 3,207-bp-long nucleotide sequence and a 417-nucleotide-long small ORF located within the N-terminal half of the large ORF, but in a different reading frame. The large ORF was found to encode a polyprotein cotranslationally processed by the viral protease VP4 to generate pVP2 (the VP2 precursor), a 71-amino-acid-long peptide ([X]), VP4, and VP3. The two cleavage sites at the [X]-VP4 and VP4-VP3 junctions were identified by N-terminal sequencing. We showed that the processing of pVP2 generated VP2 and several small peptides (amino acids [aa] 418 to 460, 461 to 467, 468 to 474, and 475 to 486). Two of these peptides (aa 418 to 460 and 475 to 486) were positively identified in the viral particles with 10 additional peptides derived from further processing of the peptide aa 418 to 460. The results suggest that VP4 cleaves multiple Pro-X-Ala↓Ala motifs, with the notable exception of the VP4-VP3 junction. Replacement of the members of the predicted VP4 catalytic dyad (Ser-692 and Lys-729) confirmed their indispensability in the polyprotein processing. The genomic segment B sequence revealed a single large ORF encoding a putative polymerase, VP1. Our results demonstrate that BSNV should be considered a new aquatic birnaVirus species, slightly more related to IBDV than to IPNV.

Bruno Costa - One of the best experts on this subject based on the ideXlab platform.

  • Genome and polypeptides characterization of Tellina Virus 1 reveals a fifth genetic cluster in the Birnaviridae family
    Virology, 2008
    Co-Authors: Isabelle Nobiron, Bruno Costa, Celine Henry, Pierre Boudinot, Marie Galloux, Corinne Torhy, Nathalie Lejal, Bernard Delmas
    Abstract:

    We characterized tellina Virus 1 (TV-1), a birnaVirus isolated from the marine bivalve mollusk Tellina tenuis. Genome sequence analysis established that TV-1 is representative of a viral cluster distant from other birnaViruses. The maturation process of the polyprotein encoded by the genomic segment A was delineated with the identification of the N-termini of the viral protease VP4 and the ribonucleoprotein VP3, and the characterization of peptides deriving from the processing of pVP2, the VP2 capsid protein precursor. One of these peptides was shown to possess a membrane-disrupting domain. Like the blotched Snakehead Virus, the polyprotein exhibits a non-structural polypeptide (named [X]) located between pVP2 and VP4. Mutagenesis analysis allowed the identification in VP4 of a catalytic Ser-Lys dyad that does not possess the common Gly-X-Ser signature of the serine hydrolases. The genomic segment B encodes the viral RNA-dependent RNA-polymerase VP1 with the unique sequence motif arrangement identified in other birnaVirus VP1s.

  • blotched Snakehead Virus is a new aquatic birnaVirus that is slightly more related to avibirnaVirus than to aquabirnaVirus
    Journal of Virology, 2003
    Co-Authors: Bruno Costa, Stephanie Soignier, Corinne Thory, Jeanclaude Huet, Christophe Chevalier, Celine Henry, Bernard Delmas
    Abstract:

    By different approaches, we characterized the birnaVirus blotched Snakehead Virus (BSNV). The sequence of genomic segment A revealed the presence of two open reading frames (ORFs): a large ORF with a 3,207-bp-long nucleotide sequence and a 417-nucleotide-long small ORF located within the N-terminal half of the large ORF, but in a different reading frame. The large ORF was found to encode a polyprotein cotranslationally processed by the viral protease VP4 to generate pVP2 (the VP2 precursor), a 71-amino-acid-long peptide ([X]), VP4, and VP3. The two cleavage sites at the [X]-VP4 and VP4-VP3 junctions were identified by N-terminal sequencing. We showed that the processing of pVP2 generated VP2 and several small peptides (amino acids [aa] 418 to 460, 461 to 467, 468 to 474, and 475 to 486). Two of these peptides (aa 418 to 460 and 475 to 486) were positively identified in the viral particles with 10 additional peptides derived from further processing of the peptide aa 418 to 460. The results suggest that VP4 cleaves multiple Pro-X-Ala↓Ala motifs, with the notable exception of the VP4-VP3 junction. Replacement of the members of the predicted VP4 catalytic dyad (Ser-692 and Lys-729) confirmed their indispensability in the polyprotein processing. The genomic segment B sequence revealed a single large ORF encoding a putative polymerase, VP1. Our results demonstrate that BSNV should be considered a new aquatic birnaVirus species, slightly more related to IBDV than to IPNV.

Mark Paetzel - One of the best experts on this subject based on the ideXlab platform.

  • Crystal structure of the VP4 protease from infectious pancreatic necrosis Virus reveals the acyl-enzyme complex for an intermolecular self-cleavage reaction
    Journal of Biological Chemistry, 2007
    Co-Authors: Jaeyong Lee, Bernard Delmas, Anat R Feldman, Mark Paetzel
    Abstract:

    Infectious pancreatic necrosis Virus (IPNV), an aquatic birnaVirus that infects salmonid fish, encodes a large polyprotein (NH2-pVP2-VP4-VP3-COOH) that is processed through the proteolytic activity of its own protease, VP4, to release the proteins pVP2 and VP3. pVP2 is further processed to give rise to the capsid protein VP2 and three peptides that are incorporated into the virion. Reported here are two crystal structures of the IPNV VP4 protease solved from two different crystal symmetries. The electron density at the active site in the triclinic crystal form, refined to 2.2-A˚ resolution, reveals the acyl-enzyme complex formed with an internalVP4cleavage site. The complex was generated using a truncated enzyme in which the general base lysine was substituted. Inside the complex, the nucleophilic Ser633O_ forms an ester bond with the main-chain carbonyl of the C-terminal residue, Ala716, of a neighboring VP4. The structure of this substrate-VP4 complex allows us to identify the S1, S3, S5, and S6 substrate binding pockets as well as other substrate- VP4 interactions and therefore provides structural insights into the substrate specificity of this enzyme. The structure from the hexagonal crystal form, refined to 2.3-A˚ resolution, reveals the free-binding site of the protease. Three-dimensional alignment with the VP4 of blotched Snakehead Virus, another birnaVirus, shows that the overall structure of VP4 is conserved despite a low level of sequence identity (_19%). The structure determinations of IPNV VP4, the first of an acyl-enzyme complex for a Ser/Lys dyad protease, provide insights into the catalytic mechanism and substrate recognition of this type of protease.

  • Expression, purification and crystallization of a birnaVirus-encoded protease, VP4, from blotched Snakehead Virus (BSNV)
    Acta Crystallographica Section F: Structural Biology and Crystallization Communications, 2006
    Co-Authors: Jaeyong Lee, Bernard Delmas, Anat R Feldman, Mark Paetzel
    Abstract:

    Blotched Snakehead Virus (BSNV) is a member of the Birnaviridae family that requires a virally encoded protease known as VP4 in order to process its polyprotein into viral capsid protein precursors (pVP2 and VP3). VP4 belongs to a family of serine proteases that utilize a serine/lysine catalytic dyad mechanism. A mutant construct of VP4 with a short C-terminal truncation was overexpressed in Escherichia coli and purified to homogeneity for crystallization. Using the sitting-drop vapour-diffusion method at room temperature, protein crystals with two distinct morphologies were observed. Cubic crystals grown in PEG 2000 MME and magnesium acetate at pH 8.5 belong to space group I23, with unit-cell parameters a = b = c = 143.8 A ° . Trigonal crystals grown in ammonium sulfate and glycerol at pH 8.5 belong to space group P321/P312, with unit-cell parameters a = b = 158.2, c = 126.4 A ° .

Celine Henry - One of the best experts on this subject based on the ideXlab platform.

  • Genome and polypeptides characterization of Tellina Virus 1 reveals a fifth genetic cluster in the Birnaviridae family
    Virology, 2008
    Co-Authors: Isabelle Nobiron, Bruno Costa, Celine Henry, Pierre Boudinot, Marie Galloux, Corinne Torhy, Nathalie Lejal, Bernard Delmas
    Abstract:

    We characterized tellina Virus 1 (TV-1), a birnaVirus isolated from the marine bivalve mollusk Tellina tenuis. Genome sequence analysis established that TV-1 is representative of a viral cluster distant from other birnaViruses. The maturation process of the polyprotein encoded by the genomic segment A was delineated with the identification of the N-termini of the viral protease VP4 and the ribonucleoprotein VP3, and the characterization of peptides deriving from the processing of pVP2, the VP2 capsid protein precursor. One of these peptides was shown to possess a membrane-disrupting domain. Like the blotched Snakehead Virus, the polyprotein exhibits a non-structural polypeptide (named [X]) located between pVP2 and VP4. Mutagenesis analysis allowed the identification in VP4 of a catalytic Ser-Lys dyad that does not possess the common Gly-X-Ser signature of the serine hydrolases. The genomic segment B encodes the viral RNA-dependent RNA-polymerase VP1 with the unique sequence motif arrangement identified in other birnaVirus VP1s.

  • blotched Snakehead Virus is a new aquatic birnaVirus that is slightly more related to avibirnaVirus than to aquabirnaVirus
    Journal of Virology, 2003
    Co-Authors: Bruno Costa, Stephanie Soignier, Corinne Thory, Jeanclaude Huet, Christophe Chevalier, Celine Henry, Bernard Delmas
    Abstract:

    By different approaches, we characterized the birnaVirus blotched Snakehead Virus (BSNV). The sequence of genomic segment A revealed the presence of two open reading frames (ORFs): a large ORF with a 3,207-bp-long nucleotide sequence and a 417-nucleotide-long small ORF located within the N-terminal half of the large ORF, but in a different reading frame. The large ORF was found to encode a polyprotein cotranslationally processed by the viral protease VP4 to generate pVP2 (the VP2 precursor), a 71-amino-acid-long peptide ([X]), VP4, and VP3. The two cleavage sites at the [X]-VP4 and VP4-VP3 junctions were identified by N-terminal sequencing. We showed that the processing of pVP2 generated VP2 and several small peptides (amino acids [aa] 418 to 460, 461 to 467, 468 to 474, and 475 to 486). Two of these peptides (aa 418 to 460 and 475 to 486) were positively identified in the viral particles with 10 additional peptides derived from further processing of the peptide aa 418 to 460. The results suggest that VP4 cleaves multiple Pro-X-Ala↓Ala motifs, with the notable exception of the VP4-VP3 junction. Replacement of the members of the predicted VP4 catalytic dyad (Ser-692 and Lys-729) confirmed their indispensability in the polyprotein processing. The genomic segment B sequence revealed a single large ORF encoding a putative polymerase, VP1. Our results demonstrate that BSNV should be considered a new aquatic birnaVirus species, slightly more related to IBDV than to IPNV.

Jaeyong Lee - One of the best experts on this subject based on the ideXlab platform.

  • Crystal structure of the VP4 protease from infectious pancreatic necrosis Virus reveals the acyl-enzyme complex for an intermolecular self-cleavage reaction
    Journal of Biological Chemistry, 2007
    Co-Authors: Jaeyong Lee, Bernard Delmas, Anat R Feldman, Mark Paetzel
    Abstract:

    Infectious pancreatic necrosis Virus (IPNV), an aquatic birnaVirus that infects salmonid fish, encodes a large polyprotein (NH2-pVP2-VP4-VP3-COOH) that is processed through the proteolytic activity of its own protease, VP4, to release the proteins pVP2 and VP3. pVP2 is further processed to give rise to the capsid protein VP2 and three peptides that are incorporated into the virion. Reported here are two crystal structures of the IPNV VP4 protease solved from two different crystal symmetries. The electron density at the active site in the triclinic crystal form, refined to 2.2-A˚ resolution, reveals the acyl-enzyme complex formed with an internalVP4cleavage site. The complex was generated using a truncated enzyme in which the general base lysine was substituted. Inside the complex, the nucleophilic Ser633O_ forms an ester bond with the main-chain carbonyl of the C-terminal residue, Ala716, of a neighboring VP4. The structure of this substrate-VP4 complex allows us to identify the S1, S3, S5, and S6 substrate binding pockets as well as other substrate- VP4 interactions and therefore provides structural insights into the substrate specificity of this enzyme. The structure from the hexagonal crystal form, refined to 2.3-A˚ resolution, reveals the free-binding site of the protease. Three-dimensional alignment with the VP4 of blotched Snakehead Virus, another birnaVirus, shows that the overall structure of VP4 is conserved despite a low level of sequence identity (_19%). The structure determinations of IPNV VP4, the first of an acyl-enzyme complex for a Ser/Lys dyad protease, provide insights into the catalytic mechanism and substrate recognition of this type of protease.

  • Expression, purification and crystallization of a birnaVirus-encoded protease, VP4, from blotched Snakehead Virus (BSNV)
    Acta Crystallographica Section F: Structural Biology and Crystallization Communications, 2006
    Co-Authors: Jaeyong Lee, Bernard Delmas, Anat R Feldman, Mark Paetzel
    Abstract:

    Blotched Snakehead Virus (BSNV) is a member of the Birnaviridae family that requires a virally encoded protease known as VP4 in order to process its polyprotein into viral capsid protein precursors (pVP2 and VP3). VP4 belongs to a family of serine proteases that utilize a serine/lysine catalytic dyad mechanism. A mutant construct of VP4 with a short C-terminal truncation was overexpressed in Escherichia coli and purified to homogeneity for crystallization. Using the sitting-drop vapour-diffusion method at room temperature, protein crystals with two distinct morphologies were observed. Cubic crystals grown in PEG 2000 MME and magnesium acetate at pH 8.5 belong to space group I23, with unit-cell parameters a = b = c = 143.8 A ° . Trigonal crystals grown in ammonium sulfate and glycerol at pH 8.5 belong to space group P321/P312, with unit-cell parameters a = b = 158.2, c = 126.4 A ° .

  • crystallization communications Acta Cryst. (2006). F62, 353–356 doi:10.1107/S1744309106006403 353 Acta Crystallographica Section F Structural Biology
    2006
    Co-Authors: Jaeyong Lee, Anat A R. Feldman, Bernard Delmasb
    Abstract:

    Expression, purification and crystallization of a birnaVirus-encoded protease, VP4, from blotched Snakehead Virus (BSNV