Purification and properties ofα-amylase from chicken (Gallus Gallus L.) pancreas

Summary

Amylase from chicken pancreas was purified by an affinity method involving filtering a crude extract from pancreas through a Sepharose-wheat albumin column and eluting the retained enzyme with maltose. The purified amylase showed two active bands upon polyacrylamide electrophoresis in an alkaline buffer system and only one band in an acidic buffer system. The enzyme is a Ca²⁺—glycoprotein which behaves as a typicalα-amylase. It consists of a single polypeptide chain with molecular weight 53,000 and contains 5.3 moles of reducing sugars per mole of protein. Optimal conditions of pH and temperature for the enzymic activity are 7.5 and 37°C. The enzyme is irreversibly inactivated by removal of Ca²⁺ by exhaustive dialysis and is activated by the presence in the assay mixture of Cl⁻; other halides are less effective than Cl⁻ in activating the enzyme.