A new type of enzyme, an exo-splitting α-1,3 glucanase from non-induced cultures of Aspergillus nidulans

Abstract

1. 1.|A new type of enzyme has been isolated and characterized as an exo-splitting α-1,3 glucanase; this enzyme is produced by Aspergillus nidulans. 2. 2.|It is not necessary to induce the enzyme; both the substrate (α-1,3 glucan) and α-1,3 glucanase are isolated from the same organism. 3. 3.|The enzyme degrades α-1,3 glucan to glucose but is inactive on glucan with mixed α-1,3 and α-1,4 linkages (nigeran). 4. 4.|The enzyme has the following properties: K m (g/ml) is 1.6·10 −3, the pH optimum lies between 5 and 6.2; the temperature optimum lies at 50°; it is shown to be an exo-enzyme; its activity is not inhibited by Mg 2+, Zn 2+, Cu 2+, EDTA or glucose.