Induction of cellulose in Schizophyllum commune: thiocellobiose as a new inducer

Abstract

Several mono-, di-, tetra- and polysaccharides were screened for their ability to induce cellulase production by the tetrapolar hymenocyte S. commune. Of 21 carbohydrates screened, 4 (thiocellobiose, carboxymethylcellulose, cellobiose and xylan) induced all 3 enzymes tested (carboxymethylcellulase, .beta.-glucosidase and xylanase). The inducing effect increased with rising concentrations of the inducers up to a certain value, beyond which there was either a leveling off or a decrease of the enzymatic activities. The most powerful inducer, thiocellobiose, showed the highest activity at 0.5 mM. Cellobiose, carboxymethylcellulose and xylan showed their highest activities at 1 mM and 1%, respectively. Sophorose did not enhance enzyme production. The enzymatic activities were monitored over a period of 24 h. Thiocellobiose elicited a response immediately after incubation but with all other inducers there was a latency period before their effect could be measured. High-performance liquid chromatography showed no hydrolysis of thiocellobiose when incubated in the presence of S. commune extracellular enzymes.