Preparative purification of adenosine deaminase from human erythrocytes by affinity chromatography

The purification of adenosine deaminase from human erythrocytes is reported. By means of classical procedures and by using affinity chromatography as the last step, the enzyme is purified 760,000-fold with a yield of 32%. The affinity resin is composed of purine riboside (nebularine) linked to Sepharose CL6B. Since the compound has no leaving group at the C-6 position the affinity gel is stable and the chromatography can be repeated several times (up to fifteen times in eight months). Purine riboside was chosen because its potency as a reversible inhibitor of adenosine deaminase is greater than that of inosine (a low-affinity inhibitor), but lower than that of erythro-9-(2-hydroxy-3-nonyl)adenine (a high-affinity inhibitor).