Studies on Dog Saliva III. Observations on Enzymes Acting on Ester Bonds and Glycosyl Compounds

Abstract

Hydrolases acting on ester bonds and glycosyl compounds were studied in the supernatant and sediment fraction of centrifuged dog saliva. When comparing the values obtained to those of man the most interesting deviations were: (1) the lack of a-amylase in dog saliva. (2) the low activity in dog saliva towards 6-bromo-2-naphthyl-α-D-glucoside and glucuronide, (3) the low activity towards 1-naphthyl phosphate at the acidic pH in dog saliva, and (4) the lack of enzymes hydrolyzing 6-bromo-2-naphthyl sulphate in the dog saliva supernatant fraction. The enzymes of centrifuged dog saliva and its sediment were fractionated with Sephadex G-200 and DEAE-cellulose columns. DEAE-cellulose chromatography brought out three enzyme peaks with phosphomonoester hydrolase activity, one of which was active at a wide pH range, one at the acidic side and one at the alkaline side. Two enzyme peaks hydrolyzing 6-bromo-2-naphthyl sulphate were obtained with DEAE-cellulose chromatography from the sediment fraction of dog saliva. The hydrolysis of carboxylic acid esters was observed in several enzyme peaks both from the supernatant and sediment fractions. The chromatographic results resembled those obtained with man.