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Enhancement of single-molecule fluorescence signals by colloidal silver nanoparticles in studies of protein translation.

ABSTRACT: Metal-enhanced fluorescence (MEF) increased total photon emission of Cy3- and Cy5-labeled ribosomal initiation complexes near 50 nm silver particles 4- and 5.5-fold, respectively. Fluorescence intensity fluctuations above shot noise, at 0.1-5 Hz, were greater on silver particles. Overall signal-to-noise ratio was similar or slightly improved near the particles. Proximity to silver particles did not compromise ribosome function, as measured by codon-dependent binding of fluorescent tRNA, dynamics of fluorescence resonance energy transfer between adjacent tRNAs in the ribosome, and tRNA translocation induced by elongation factor G.

SUBMITTER: Bharill S

PROVIDER: S-EPMC3049198 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature

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Enhancement of single-molecule fluorescence signals by colloidal silver nanoparticles in studies of protein translation.

Bharill Shashank S Chen Chunlai C Stevens Benjamin B Kaur Jaskiran J Smilansky Zeev Z Mandecki Wlodek W Gryczynski Ignacy I Gryczynski Zygmunt Z Cooperman Barry S BS Goldman Yale E YE

ACS nano 20101216 1

Metal-enhanced fluorescence (MEF) increased total photon emission of Cy3- and Cy5-labeled ribosomal initiation complexes near 50 nm silver particles 4- and 5.5-fold, respectively. Fluorescence intensity fluctuations above shot noise, at 0.1-5 Hz, were greater on silver particles. Overall signal-to-noise ratio was similar or slightly improved near the particles. Proximity to silver particles did not compromise ribosome function, as measured by codon-dependent binding of fluorescent tRNA, dynamics ...[more]

PMID: 21158483

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