AFFINITY PURIFICATION AND CHARACTERIZATION OF A BETA-1,3-GLUCANASE FROM CELERY

beta-1,3-glucanase was purified in a single column step from crude root extracts of celery, Apium graveolens L. using a novel affinity chromatography procedure. The beta-1,3-glucanase was bound to an insoluble anhydroglucose substrate (pachyman) and then eluted by the addition of a soluble substrate (laminarin). The celery enzyme has an isoelectric point of 4.1, an estimated molecular mass of 35 kDa, maximum endo-beta-l,3-glucanase activity at pH 5.2 and a turnover rate of similar to 2800 nmol substrate/nmol enzyme/min with laminarin as substrate. The purified enzyme partially hydrolyzed isolated cell walls of the celery wilt pathogen, Fusarium oxysporum Schlect f. sp. apii (R. Nels. and Sherb.) Snyd. and Hans.; its activity was substantially increased by the addition of crude root extract containing chitinase. Chitinase activity on the fungal cell walls was not enhanced by supplementing crude root extract with additional purified beta-1,3-glucanase.