1.13.12.4	0°C, crystalline suspension at 2-10 mg per ml for at least 6 months without loss of activity in the dark	
1.13.12.4	4°C, 1 M sodium acetate buffer, pH 5.7, in the dark	
1.13.12.4	4°C, 80% saturated ammonium sulfate in the dark	
1.13.12.4	4°C, crystalline suspension in 1 M sodium acetate buffer, pH 5.4, in the dark	
1.13.12.4	5°C, crystalline suspension in ammonium sulfate, several months, no loss of activity