Hydrolytic enzymes in bovine skeletal muscle. I. Starch gel electrophoretic separation and properties of soluble esterases.

Abstract

Water-soluble esterases of certain bovine skeletal muscles were separated by horizontal zone electrophoresis in starch gel in a discontinuous ouffer system. Eighteen bands of esterase activity were detected by the use of α-naphthyl acetate and α-naphthyl butyrate as substrates. Other substrates and various inhibitors were used to characterize the separated enzymes. A group of presumed isozymic esterases (three bands), which hydrolyzed α-naphthyl butyrate but not any other substrate tested, was sensitive to organophosphates, was heat labile, and was classified as aliesterase or, more specifically, as butyrylesterase. Another group of presumed isozymic esterases (four bands) hydrolyzed only α-naphthyl acetate and indoxyl acetates, was heat stable and resistant to organophosphates, and was tentatively classified as arylesterase or cathepsin. Eleven heat-labile esterase bands hydrolyzed both α-naphthyl acetate and α-naphthyl butyrate, were sensitive to organophosphates, and were classified as nonspecific aliesterases.