A simple and rapid procedure for the large scale purification of the recA protein of Escherichia coli.

A simple and rapid three-step procedure for the large scale purification of the recA protein of Escherichia coli is described. The method depends primarily on a single chromatographic step which is highly specific for recA protein: elution by ATP from single-stranded DNA cellulose. With this procedure, gram quantities of recA protein, greater than 99% pure, can be reproducibility prepared for biochemical and biophysical analysis.