Formation and Location of 1,4-β-Glucanases and 1,4-β-Glucosidases from Penicillium janthinellum

Abstract

Formation and location of 1,4-β-glucanases and 1,4-β-glucosidases were studied in cultures of Penicillium janthinellum grown on Avicel, sodium carboxymethyl cellulose, cellobiose, glucose, mannose, and maltose. Endo-1,4-β-glucanases were found to be cell free, and their formation was induced by cellobiose. 1,4-β-Glucosidases, on the other hand, were formed constitutively and were primarily cell free, but with a small amount strongly associated with the cell wall. Low 1,4-β-glucosidase activities of periplasmic or intracellular origin were also found. A rotational viscosimetric method was developed to measure the total endo-1,4-β-glucanase activity of the culture (broth and solids). By this method, it was possible to determine the endo-1,4-β-glucanase activity not only in the supernatant of the culture but also on the surface of the mycelium or absorbed on residual Avicel. During a 70-liter batch cultivation of P. janthinellum , the adsorption of endo-1,4-β-glucanases by residual and newly added 10% Avicel was measured. The adsorption of soluble protein and endo-1,4-β-glucanases by Avicel was found to be largely independent of the pH value but dependent on temperature.