The Purification and Properties of the Aspartate Aminotransferase and Aromatic‐Amino‐Acid Aminotransferase from Escherichia coli

Abstract

A simple and convenient procedure is described for the isolation in good yield of two amionotransferases from various strains of Escherichia coli. On the basis of thier substrate specificities on of the enzymes has been classified as an aromatic amino acid aminotransferase and the other as an aspartate aminotransferate. But both act on a wide range of substrates Pyridioxal phosphate is bound more strongly to the aspartate aminotransferate than to the aromatic amino transferase which cannot be fully re-activated afer removal of the prosthetic group. Both enzymes are composed of two subunits which appear to be identical.