Synthesis of a disulfide affinity adsorbent for purification of estrogen receptor

Synthesis of an estrogen affinity adsorbent containing a disulfide linkage between the steroid and stationary matrix permitted facile purification of high affinity estrogen binding proteins. Following affinity chromatography of either antibody directed against estrone 17-carboxymethyloxime - bovine serum albumin or immature calf uterine cytoplasmic estrogen receptor proteins, the specifically bound mercaptoethanol. Crude antibody and uterine cytosol was 10(-3) to 10(-2)M cystamine (S-S) to block SH-containing proteins, in order to protect the adsorbent against protein-mediated S-S in equilibrium SH exchange. Cystamine was found to markedly stabilize crude cytosol receptor protein by 200-300% compared with preparations obtained under ordinary conditions. Disulfide affinity adsorbents are versatile in that they can be used either under conventional conditions of specific protein recovery, or with 2-mercaptoethanol which removes the ligand and bound protein from the stationary matrix quantitatively.