Human amylase isoenzymes separated on concanavalin A--Sepharose

Abstract

Human salivary amylase and pancreatic amylase were purified and characterized. These amylases gave two bands and one band, respectively, each staining for both protein and sugar, after electrophoresis on sodium dodecyl sulfate--polyacrylamide gel. The relative molecular mass (Mr) or pancreatic amylase was calculated to be 60 000; for the two components (A and B) of salivary amylase the Mr were 61 000 and 64 000. The two salivary amylases were separated by chromatography on concanavalin A--Sepharose; only component B bound to concanavalin A. The carbohydrate content of pancreatic amylase was 1.61 +/- 1.02% (SD), and of salivary amylases A and B 2. 18 +/- 0.71% and 8.77 +/- 2.28%, respectively. The salivary and pancreatic amylases had completely identical antigenicities against antibody to either. On isoelectric focusing, pancreatic amylase showed one peak at pH 7.0, salivary amylase A showed a major peak at pH 6.4 WITH A TRACE OF MATERIAL At pH 5.9, and salivary amylase B a major peak at pH 5.9 and one minor peak at pH 6.4. Serum amylase was separated into two major peaks with isoelectric points (pl) of 6.4 and 7.0, respectively, and one minor peak, with a pl of 5.9. Only a small part of the serum amylase with a pl of 5.9 combined with concanavalin A; the two other serum amylases did not.