Localization of the sulfur‐cyanolysis site of serum albumin to subdomain 3‐ab

Abstract The results of kinetic experiments measuring the effects of a variety of ligands on the sulfur‐cyanolysis reaction catalyzed by serum albumin point to the conclusion that the active site for cyanolysis is on subdomain 3‐AB. Relationships among the inhibition by short‐chain fatty acids, the activation by p ‐nitrophenyl acetate, and the influence of bilirubin and L‐tryptophan on these effects indicate that the cyanolysis active site and the known primary binding site for indoles are both near, but on opposite sides of, tyrosine‐409 of bovine albumin (tyrosine‐411 of human albumin).