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Functional characterization and atomic force microscopy of a DNA repair protein conjugated to a quantum dot.

ABSTRACT: Quantum dots (QDs) possess highly desirable optical properties that make them ideal fluorescent labels for studying the dynamic behavior of proteins. However, a lack of characterization methods for reliably determining protein-quantum dot conjugate stoichiometry and functionality has impeded their widespread use in single-molecule studies. We used atomic force microscopic (AFM) imaging to demonstrate the 1:1 formation of UvrB-QD conjugates based on an antibody-sandwich method. We show that an agarose gel-based electrophoresis mobility shift assay and AFM can be used to evaluate the DNA binding function of UvrB-QD conjugates. Importantly, we demonstrate that quantum dots can serve as a molecular marker to unambiguously identify the presence of a labeled protein in AFM images.

SUBMITTER: Wang H

PROVIDER: S-EPMC3941028 | biostudies-literature | 2008 Jun

REPOSITORIES: biostudies-literature

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Functional characterization and atomic force microscopy of a DNA repair protein conjugated to a quantum dot.

Wang Hong H Tessmer Ingrid I Croteau Deborah L DL Erie Dorothy A DA Van Houten Bennett B

Nano letters 20080430 6

Quantum dots (QDs) possess highly desirable optical properties that make them ideal fluorescent labels for studying the dynamic behavior of proteins. However, a lack of characterization methods for reliably determining protein-quantum dot conjugate stoichiometry and functionality has impeded their widespread use in single-molecule studies. We used atomic force microscopic (AFM) imaging to demonstrate the 1:1 formation of UvrB-QD conjugates based on an antibody-sandwich method. We show that an ag ...[more]

PMID: 18444686

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