title: Crosslinking of and coupling to viral capsid proteins by tyrosine oxidation.
abstract: Cowpea mosaic virus is composed of 60 identical copies of a two-subunit protein organized in pentameric assemblies around the icosahedral 5-fold symmetry axis. Treatment of the virus with the Ni(II) complex of the tripeptide GGH and a peroxide oxidant, or irradiation in the presence of Ru(bpy)(3)(2+) and persulfate generates covalent crosslinks across the pentameric subunit boundaries, effectively stitching the subunits together. Intersubunit crosslinking was found to occur exclusively at adjacent tyrosine residues (Y52-Y103), as predicted from the X-ray crystal structure of the capsid, and to be more extensive with the photochemical ruthenium system. The Ni/GGH oxidative procedure was also used to make covalent attachments to the virion by trapping with a functionalized disulfide reagent.
authors.affiliation: Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N Torrey Pines Road, La Jolla, CA 92037, USA.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Meunier
authors.forename: Erica
authors.initials: E
authors.lastname: Strable
authors.forename: M G
authors.initials: MG
authors.lastname: Finn
mesh_terms: D036022:Capsid Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D017798:Comovirus / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D003432:Cross-Linking Reagents / Q000737:chemistry*; D018360:Crystallography, X-Ray; D003545:Cysteine / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008958:Models, Molecular; D015394:Molecular Structure; D009154:Mutation / Q000235:genetics; D009532:Nickel / Q000737:chemistry; D010084:Oxidation-Reduction; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D010777:Photochemistry; D010795:Phthalic Acids / Q000737:chemistry; D020836:Protein Structure, Quaternary; D012428:Ruthenium / Q000737:chemistry; D013057:Spectrum Analysis; D013696:Temperature; D014443:Tyrosine / Q000235:genetics / Q000378:metabolism*; D014771:Virion / Q000737:chemistry / Q000378:metabolism
chemical_list: D036022:Capsid Proteins; D003432:Cross-Linking Reagents; D010455:Peptides; D010795:Phthalic Acids; D014443:Tyrosine; D009532:Nickel; D012428:Ruthenium; D003545:Cysteine; C044731:magnesium monoperoxyphthalate