@article{mbs:/content/journal/micro/10.1099/00221287-136-7-1321, author = "Strauss, Josef and Kubicek, Christian P.", title = "β-Glucosidase and cellulase formation by a Trichoderma reesei mutant defective in constitutive β-glucosidase formation", journal= "Microbiology", year = "1990", volume = "136", number = "7", pages = "1321-1326", doi = "https://doi.org/10.1099/00221287-136-7-1321", url = "https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-136-7-1321", publisher = "Microbiology Society", issn = "1465-2080", type = "Journal Article", abstract = "A mutant of Trichoderma reesei QM 9414 - T. reesei M8 - was isolated after γ-irradiation. It did not form β-glucosidase during growth on glycerol or glucose, but secreted β-glucosidase upon growth on cellobiose. The mutant was also able to grow on cellulose and secrete β-glucosidase, but with a longer lag. β-Glucosidase activity could be induced in the mutant in a replacement medium by cellobiose and β-methyl d-glucoside. Mycelia lacking β-glucosidase were able to take up both these inducers immediately, indicating the presence of a constitutive permease. The mutant produced cellulases upon growth on lactose and - after a lag - on cellulose. Mycelia of T. reesei M8 pregrown on glycerol or cellobiose could be induced by sophorose to produce cellobiohydrolase I in a replacement system. The findings show that (i) cellobiose and other β-linked disaccharides can be taken up by T. reesei without prior hydrolysis, and (ii) that cellobiose most probably induces β-glucosidase formation during growth on cellulose.", }