On the determination of deoxyribonucleic acid-protein interaction parameters using the nitrocellulose filter-binding assay

Abstract
The effects of filter efficiency on DNA-protein binding data obtained by the popular nitrocellulose filter-binding assay are examined. Graphical procedures for determining the efficiency parameter .epsilon. (for the efficiency of retention of DNA on the filter, per bound protein molecule) are established. Filter efficiency modified formulas for determining thermodynamic binding parameters are derived for 4 simple prototypes of DNA-protein binding systems. The effects of experimental error on discrimination between models are considered. Finally, conceptual errors often made in calculating binding stoichiometry from filter-binding experiments are discussed and a general protocol for the analysis of filter-binding data is suggested.