title: Induction of Cellulase by Gentiobiose and Its Sulfur-Containing Analog in Penicillium purpurogenum.
abstract: Cellulase induction by beta-glucodisaccharides was investigated by using non-cellulase-induced mycelia of Penicillium purpurogenum P-26, a highly-cellulase-producing fungus. Gentiobiose induced significant amounts of cellulase compared with cellobiose when nojirimycin was added to the induction medium to inhibit extracellular beta-glucosidase activity. Thiogentiobiose (6-S-beta-d-glucopyranosyl-6-thio-d-glucose), a sulfur-containing analog of gentiobiose, was more effective for cellulase induction than gentiobiose even in the absence of nojirimycin. Thiogentiobiose appeared to be a gratuitous inducer since it was not metabolized during cellulase induction. Gentiobiose was formed from cellobiose by the intracellular beta-glucosidase of P. purpurogenum. These findings indicate that gentiobiose is an active inducer of cellulase for this fungus and may possibly be formed by intracellular beta-glucosidase from cellobiose.
authors.affiliation: Department of Agricultural Biochemistry, Faculty of Agriculture, Hokkaido University, Sapporo 060, and Fermentation Research Institute, Agency of Industrial Science and Technology, Tsukuba, Ibaraki 305, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kurasawa
authors.forename: M
authors.initials: M
authors.lastname: Yachi
authors.forename: M
authors.initials: M
authors.lastname: Suto
authors.forename: Y
authors.initials: Y
authors.lastname: Kamagata
authors.forename: S
authors.initials: S
authors.lastname: Takao
authors.forename: F
authors.initials: F
authors.lastname: Tomita