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Updated: Jun 13, 2025
An Optimized Single-Molecule Pull-Down Assay for Quantification of Protein Phosphorylation
Published on: June 6, 2022
Electrokinetic Detection of Single-Molecule Phosphorylation
1Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, United States.
Abstract:
Current single-molecule fluorescence experiments lack direct sensitivity to molecular phosphorylation states. We show that electrokinetic properties measured with an anti-Brownian trap resolve the number of phosphorylated sites on individual biomolecules and can monitor phosphorylation cycles with single kinase turnovers. As an application, we directly visualize the rate-limiting step in the kinase catalytic cycle.
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