SOURCE. Human pancreas.
3X crystallized. Lyophilized from a solution containing NaCl, CaCl2 and tris buffer pH 7.5 at 25° C. Each 0.1 mg contains about 50% salts.
Store at 5° C. Stable 9-12 months at 5° C.
900-950 units per mg of protein.
One unit will liberate 1 µM of reducing groups equivalent to maltose per minute at pH 6.9 and 37° C. Substrate is soluble starch.
Crystallized by our modification of the method of Levitzki et al. (29).