Induction and carbon source control of extracellular beta-glucosidase production in Acremonium persicinum

The effect of carbon source on the production of a single extracellular bet a-glucosidase by Acremonium persicinum was investigated using fast protein liquid chromatography. The enzyme was detected in the medium during growth of the fungus on a wide range of beta-glucans, particularly those containin g a high proportion of (I --> 6)-beta-linkages. While growth of A. persicin um on gentibiose, cellobiose and laminari-oligosaccharides moderately incre ased beta-glucosidase production, growth on sophorose provoked IO-fold grea ter levels of this enzyme in the culture medium. Levels of the beta-glucosi dase were minimal in the presence of even low concentrations of glucose, su crose, fructose or galactose. The results are consistent with the extracell ular A. persicinum beta-glucosidase being an inducible enzyme, subject to c arbon source control by readily metabolizable sugars, with sophorose possib ly directly inducing its synthesis.