Isoelectric focusing of milk-clotting enzymes

Abstract

Summary: Isoelectric focusing in thin-layer polyacrylamide gel has been applied successfully to the characterization and identification of calf rennet and its substitutes. The use of acidic pH gradients (pH range 2·5–6) allows the identification of calf and microbial rennets and bovine and pig pepsins.A new, very rapid and sensitive zymogram technique has been developed by overlaying the gel with a highly porous, transparent cellulose acetate film impregnated with casein.