3.5.3.2 | 4°C, 10 mM Tris-HCl buffer, pH 8, 10 mM 2-mercaptoethanol, 1.0 mM MnCl2, 70% saturated ammonium sulfate, crystalline enzyme can be stored for at least 2 months without serious loss in activity, without added Mn2+ or 2-mercaptoethanol activity rapidly lost with a half-life of about 3 days |