1.1.1.274	-70°C, 20 mM Tris-HCl, pH 7.5, over 6 months, no loss of activity	
1.1.1.274	4°C, pH 6.5-7.5, at least 2 months, no loss of activity	
1.1.1.274	4°C, purified enzyme, 400 mM potassium phoshate buffer, pH 7.0, several weeks without appreciable loss of activity