TABLE OF CONTENTS The sedimentation equilibrium (SE) technique has been in use for nearly 80 years. [1] As a result, the literature describing applications of the technique is vast. Excellent reviews have been published during the past decade [2] [6] and earlier work is also a valuable resource. [7] [10] The analysis of macromolecule ligand interactions developed over the same period and is the subject of a similarly large literature. Here, we will present results representative of recent work in our laboratories that demonstrate the promise and the challenges inherent in SE analysis of protein nucleic acid interactions and will briefly discuss advances that are likely to prove valuable in future studies. We have used the methods described here in studies of sequencespecific and non-specific DNA interactions of transcription factors, DNA repair proteins and components of the DNA-replication machinery. In addition, these approaches are likely to be useful for the analysis of interactions that modulate chromatin structure and the protein RNA interactions of ribosome assembly, tRNA charging and mRNA maturation. We hope that this review will be useful to workers in all these fields.
At SE a system of macromolecules will have a radial distribution of concentrations described by Equation (1).
Here, the summation is over all species, i; c( r) is the observed concentration at radial position r, c i ,0 the concentration of the ith species at the reference position r 0 (typically close to...
