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Mandels, Mary (Quartermaster Research and Engineering Center, Natick, Mass.), Fredrick W. Parrish, and Elwyn T. Reese . Sophorose as an inducer of cellulase in Trichoderma viride . J. Bacteriol. 83: 400–408. 1962.—The impurity in glucose responsible for cellulase induction in Trichoderma viride QM 6a has been isolated and characterized as sophorose (2-O-β- d -glucopyranosyl- d -glucose). It is present at 0.0058% in reagent grade glucose. Sophorose is a very powerful inducer of cellulase for Trichoderma viride , being 2500 times as active as cellobiose. Modifications of sophorose, such as reduction or glycoside formation, destroy its inducing ability. The high activity of sophorose as an inducer is specific for T. viride .

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ABSTRACT, .I lie soluble poly-0-D-glucan from oats has been subjected to degradation by two different types of cnzylues. "Cellulase" converts the polysaccharide to a trisaccharide, 4-0-0-~-Iaminaribiosyl-D-glucose, and two tetrasaccharides, 3'-0-~-~-ce~~obiosyl-~-ce~lobiose and 4'-0-P-Dlaminaribiosyl-D-cellobiose." Uegradatio~l by the second enzyme, "laminarinase", produces a trisaccharide, 3-O-P-~-cellobiosyl-~-&cose, and a tetrasaccharide, 3-O-p-D-~ell0tri0syl-Dgl~~cose.t These products, which account for 75-85% of the polymer in each experiment, have bee11 characterized by cl~emical methods. The data show that the glucan is composed almost entirely of two types of s t r u c t~~r a l sequences: one is a tetrameric unit in which a single P-(1 + 3) lii?l;age alternates with two P-(1 + 4) linl;ages, and the other, a pentameric unit in which a s~ngle 0-(1 + 3) linkage alternates with three consec~itive P-(1 + 4) 1inl;ages.The soluble pol!-P-D-glucan from barley has been shown by enzymolysis with the "celli~-lase" to be closely related in detailed structure to the oat polymer.Steric aspects of the enzymic degradations are discussed.

A comparison was made of exo-α-glucanases with α-glucosidases, and of exo-β1 → 3-glucanases with β-glucosidases to establish criteria for their characterization. Dimers, trimers, and tetramers of glucose are substrates for both exo-glucanases and glucosidases. Exo-glucanases act more rapidly on the longer oligomers, glucosidases on the shorter. Exo-glucanases act with inversion of configuration, glucosidases with retention. Other differences are found in transfer activity, in degree of specificity, and in susceptibility to various inhibitors.