1.5.1.30 2 12 about 80% activity retained after 24 h incubation at pH 2.0-3.5, 90 to less than 100% at pH 4.0-5.5 and pH 8.0-12.0, 100% at pH 6.0-7.5, pH 4.0-6.0 citrate-phosphate buffer, pH 6.0-7.5 potassium-phosphate buffer, pH 7.5-8.5 Tris-HCl buffer, pH 8.5-10.0 glycine-NaOH buffer 699057 1.5.1.30 6 8.5 - 392304