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Free-solution, label-free protein-protein interactions characterized by dynamic light scattering.

ABSTRACT: We report a free-solution, label-free method for quantitative characterization of macromolecular interactions using dynamic light scattering, a temperature controlled plate reader, and a multiwell concentration gradient. This nondestructive technique enabled determination of stoichiometry of binding, equilibrium dissociation constant, and thermodynamic parameters, as well as the impact of temperature, buffer salinity, and a small-molecule inhibitor. The low volume capability of dynamic light scattering reduced the required sample to 426 pmol/experiment, with detection limits for 150-kDa proteins anticipated to be in the low femtomole range.

SUBMITTER: Hanlon AD

PROVIDER: S-EPMC2808485 | biostudies-literature | 2010 Jan

REPOSITORIES: biostudies-literature

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Free-solution, label-free protein-protein interactions characterized by dynamic light scattering.

Hanlon Amy D AD Larkin Michael I MI Reddick Ryan M RM

Biophysical journal 20100101 2

We report a free-solution, label-free method for quantitative characterization of macromolecular interactions using dynamic light scattering, a temperature controlled plate reader, and a multiwell concentration gradient. This nondestructive technique enabled determination of stoichiometry of binding, equilibrium dissociation constant, and thermodynamic parameters, as well as the impact of temperature, buffer salinity, and a small-molecule inhibitor. The low volume capability of dynamic light sca ...[more]

PMID: 20338851

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