Ostrich α-amylase: Purification and characterization of the pancreatic isoenzymes

Abstract

• 1.

  1. Four ostrich pancreatic α-amylase isoenzymes were isolated by isoelectric focusing, following affinity chromatography on cyclohepta-amylose-Sepharose 4B.

• 2.

  2. Amino acid compositions of the four isoenzymes are very similar with only one charged amino acid (Arg) being significantly different.

• 3.

  3. The molecular weights, as determined by SDS-PAGE and amino acid composition, are nearly identical (52–53 kDa) for all four isoenzymes.

• 4.

  4. The four α-amylase isoenzymes appear to be kinetically distinct enzymes with a requirement for calcium.

• 5.

  5. Ostrich α-amylase isoenzymes appear to be non-glycosylated and contain one free thiol group.