title: New addresses on an addressable virus nanoblock; uniquely reactive Lys residues on cowpea mosaic virus.
abstract: Cowpea mosaic virus (CPMV) is a robust, icosahedrally symmetric platform successfully used for attaching a variety of molecular substrates including proteins, fluorescent labels, and metals. The symmetric distribution and high local concentration of the attached molecules generates novel properties for the 30 nm particles. We report new CPMV reagent particles generated by systematic replacement of surface lysines with arginine residues. The relative reactivity of each lysine on the native particle was determined, and the two most reactive lysine residues were then created as single attachment sites by replacing all other lysines with arginine residues. Structural analysis of gold derivatization not only corroborated the specific reactivity of these unique lysine residues but also demonstrated their dramatically different presentation environment. Combined with site-directed cystine mutations, it is now possible to uniquely double label CPMV, expanding its use as an addressable nanoblock.
authors.affiliation: Department of Molecular Biology, Center for Integrative Molecular Biosciences, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, USA.
authors.forename: Anju
authors.initials: A
authors.lastname: Chatterji
authors.forename: Wendy F
authors.initials: WF
authors.lastname: Ochoa
authors.forename: Melissa
authors.initials: M
authors.lastname: Paine
authors.forename: B R
authors.initials: BR
authors.lastname: Ratna
authors.forename: John E
authors.initials: JE
authors.lastname: Johnson
authors.forename: Tianwei
authors.initials: T
authors.lastname: Lin
mesh_terms: D001120:Arginine / Q000032:analysis / Q000737:chemistry; D017798:Comovirus / Q000737:chemistry* / Q000235:genetics / Q000502:physiology; D006046:Gold / Q000737:chemistry; D008239:Lysine / Q000032:analysis / Q000737:chemistry*; D008954:Models, Biological; D015394:Molecular Structure; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D017434:Protein Structure, Tertiary
chemical_list: D006046:Gold; D001120:Arginine; D008239:Lysine