A purification of Helix pomatia alpha amylase involving a novel affinity-binding procedure.

Shellfish glycogen was cross-linked by treatement with cyanogen bromide followed by 1,6-diaminohexane. The resulting, insoluble product efficiently adsorbed Helix pomatia alpha amylase [(1 linked to 4)-alpha-D-glucan glucanohydrolase] from crude solutions of the enzyme at 0 degrees, but only poorly at higher temperatures. A method was developed for the purification of Helix pomatia alpha amylase involving formation of an enzyme-adsorbent complex in the cold and recovery of the alpha amylase by suspending the washed complex in buffer at 37 degrees. After chromatography of the desorbed alpha amylase on a column of Bio-Gel P-60, the enzyme was homogenous as judged by poly(acrylamide)-gel electrophoresis. An overall purification of 360-fold was achieved with a recovery of 35%.