Measuring Protein‐Protein Interactions by Equilibrium Sedimentation

Abstract This commentary unit provides a basic introduction to the principles and practice of sedimentaiton equilibrium analytical ultracentrifugation for the study of reversible protein interactions. Equilibrium sedimentation is one of the most effective methods for the detection and characterization of protein interactions and can be applied to the measurement of self association, heterologous association, binding stoichiometry, and the determination of association constants. The unit includes an extensive discussion of the instrumentation required to carry out equilibrium analytical ultracentrifugation and to perform data analysis. A strategic planning section gives the reader several experimental scenarios and conditions for using equilibrium sedimentation.