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

Department of Biomedical Engineering, College of Engineering and College of Medicine, University of Cincinnati, Cincinnati, Ohio 45221, USA.
ACS Nano (Impact Factor: 12.03). 08/2009; 3(8):2163-70. DOI: 10.1021/nn900187k
Source: PubMed

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.

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