1.1.1.87	-20°C, ammonium sulfate precipitate, partially purified, stable	
1.1.1.87	-20°C, stable as ammonium sulfate precipitate	
1.1.1.87	0°C, pH 7.2, rapid loss of activity	
1.1.1.87	0°C, potassium phosphate 20 mM, pH 7.2, 4-5 hours