The possible function of the glucan sheath of Botrytis cinerea: effects onthe distribution of enzyme activities

The effect of a beta -1,3-glucanase (Glucanex) on cultures of Botrytis cine rea was examined. The enzyme released reducing sugars from the mycelium and from the glucan secreted into the culture medium. The morphology of the my celium was changed in the presence of Glucanex. The measured activity of gu aiacol peroxidase, laccase, and catalase was increased when the mycelium wa s treated with Glucanex. Culture of the mycelium in the presence of Glucane x resulted in an increase in catalast: activity. We suggest that the glucan plays a role in protecting the fungus from host response and may assist in the initial stages of host infection. (C) 2001 Published by Elsevier Scien ce B.V. on behalf of the Federation of European Microbiological Societies.