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Adjustable ellipsoid nanoparticles assembled from re-engineered connectors of the bacteriophage phi29 DNA packaging motor.

ABSTRACT: A 24 x 30 nm ellipsoid nanoparticle containing 84 subunits or 7 dodecamers of the re-engineered core protein of the bacteriophage phi29 DNA packaging motor was constructed. Homogeneous nanoparticles were obtained with simple one-step purification. Electron microscopy and analytical ultracentrifugation were employed to elucidate the structure, shape, size, and mechanism of assembly. The formation of this structure was mediated and stabilized by N-terminal peptide extensions. Reversal of the 84-subunit ellipsoid nanoparticle to its dodecamer subunit was controlled by the cleavage of the extended N-terminal peptide with a protease. The 84 outward-oriented C-termini were conjugated with a streptavidin binding peptide which can be used for the incorporation of markers. This further extends the application of this nanoparticle to pathogen detection and disease diagnosis by signal enhancement.

SUBMITTER: Xiao F

PROVIDER: S-EPMC2731514 | biostudies-other | 2009 Aug

REPOSITORIES: biostudies-other

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Structure of the bacteriophage phi29 DNA packaging motor.

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