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Colorful virus-like particles: fluorescent protein packaging by the Q? capsid.

ABSTRACT: Q? virus-like particles encapsulating multiple copies of fluorescent proteins were generated in high yields using a modular system enhanced by specific engineered RNA--protein interactions. The resulting particles were structurally indistinguishable from recombinant Q? alone. The encapsidated proteins were nearly identical in photochemical properties to monomeric analogues, were more stable toward thermal degradation, and were protected from proteolytic cleavage. Residues on the outer capsid surface were chemically derivatized by acylation and azide--alkyne cycloaddition without affecting the fluorescence properties of the packaged proteins. A high-affinity carbohydrate-based ligand of the CD22 receptor was thereby attached, and specific cell labeling by the particles was successfully detected by flow cytometry and confocal laser microscopy.

SUBMITTER: Rhee JK

PROVIDER: S-EPMC3246388 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature

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Colorful virus-like particles: fluorescent protein packaging by the Qβ capsid.

Rhee Jin-Kyu JK Hovlid Marisa M Fiedler Jason D JD Brown Steven D SD Manzenrieder Florian F Kitagishi Hiroaki H Nycholat Corwin C Paulson James C JC Finn M G MG

Biomacromolecules 20111013 11

Qβ virus-like particles encapsulating multiple copies of fluorescent proteins were generated in high yields using a modular system enhanced by specific engineered RNA--protein interactions. The resulting particles were structurally indistinguishable from recombinant Qβ alone. The encapsidated proteins were nearly identical in photochemical properties to monomeric analogues, were more stable toward thermal degradation, and were protected from proteolytic cleavage. Residues on the outer capsid sur ...[more]

PMID: 21995513

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Colorful virus-like particles: fluorescent protein packaging by the Q? capsid.

Publications

Colorful virus-like particles: fluorescent protein packaging by the Qβ capsid.

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