Characterization of an endo-1,3(4)-β-d-glucanase gene from Cellvibrio mixtus

Abstract

An endo-1,3(4)-β-d-glucanase gene (cwd2) of Cellvibrio mixtus encoding laminarinase activity was cloned on a 3.9-kb Pst I fragment. The Cwd2 enzyme, extracted from recombinant Escherichia coli, degraded both β-1,3 glucans and β-1,3-1,4 mixed-linkage glucans, was entohydrolytic and so conformed to the enzyme class 3.2.1.6. The pH and temperature optima of the enzyme were approximately 7 and 40°C respectively. The Mr of specifically labelled Cwd2 was approximately 34 000. This gene was quite distinct from two other C. mixtus β-1,3 glucanases previously described. © 1993.