Affinity chromatography of a regulatory enzyme based on specific interaction with the effector

A crude extract of yeast was chromatographed on a column of Sepharose containing covalently bound L-tyrosine. The tyrosine-sensitive 3-deoxy-D-arabino-heptulosonate-7-phosphate (DAHP) synthetase was retarded by the column relative to the bulk of the protein and was purified about 100-fold. In contrast, the phenylalanine-sensitive enzyme was not retarded. No retardation was found on an unsubstituted Sepharose column. The purification presumably …