Specificity of Disaccharide-splitting Enzymes

Abstract

DISAGREEMENT exists concerning the substrates which maltases of different sources can hydrolyze. According to the view advanced by Leibowitz¹, there occur in Nature two types of maltase, a gluco-maltase and a glucosido-maltase respectively. The gluco-maltase which occurs in malt and in moulds splits maltose but is inert towards alpha-glucosides and sucrose ; the glucosido-maltase which occurs in yeast splits alpha-glucosides as well as maltose. Different investigators² have applied the two maltase classification over a wide range of maltases from various sources. Weidenhagen³, however, has denied the validity of this view, and claims that in sufficient enzyme concentrations, even malt and taka-diastase hydrolyze alpha-methyl-glucoside. All maltases in Nature are said therefore to be glucosido-maltases ; they are considered to be identical with the glucosucrase among the sucrases, and to split alpha-glucosides and sucrose as well as maltose.