2.5.1.61 DTT stabilizes 2.5.1.61 enzyme is most stable in 0.3 M LiBr, 0.1 M 2-mercaptoethanol, 30% glycerol, 0.15 M Tris chloride, pH 8.0 to 9.0, or 0.3 M (NH4)2SO4 2.5.1.61 phosphate stabilizes