Mary Mandels

Measurement of saccharifying cellulase

This article sets forth a simple cellulase assay procedure. Cellulose is variable in nature, insoluble and resistant to enzymatic attack. As a result there have been a bevy of bewildering cellulase assays published that yielded irrational results. Certain protocols focused on the rapidity of the assay while ignoring that only the most readily susceptible cellulose regions were being hydrolyzed. Other assays simplified the system by using modified soluble substrates and yielded results that bore no relationship to the real world hydrolysis of insoluble cellulose. In this study Mandels, Andreotti and Roche utilized a common substrate, Whatman filter paper. Hydrolysis of a 50 mg sample of the paper was followed to roughly 4% degradation, which circumvented the problems of attack of only the most susceptible zones. This common hydrolysis target range also resulted in some balance with regard to the interaction of the several cellulase components. The method was subsequently widely adopted.Douglas E Eveleigh

A thioglucosidase in fungi

Abstract A β-thioglucosidase capable of hydrolyzing mustard oil glucosides is of rare occurrence in fungi. Aspergillus sydowi QM 31c is a good source of the enzyme. The fungal enzyme resembles mustard seed myrosinase. Both enzymes degrade sinigrin producing glucose, KHSO4, and allyl isothiocyanate. They attack only the mustard oil thioglucosides, and are inactive on thioglucosides not having this configuration. The fungal enzyme is relatively more active on sinalbin and glucotropaeolin than is myrosinase. The fungal enzyme is less resistant to heat, acids, alkalies, and chemical inhibitors than is the mustard enzyme.

Rolling with the Times: Production and Applications of Trichoderma reesei CELLULASE

A review on Trichoderma reese as the best available source of extracellular cellulase. (Refs. 56).

β-(1→3) Glucanases from plant callus cultures☆

Abstract Enzymes capable of hydrolyzng β-(1→3) glucan (laminarin) have been found in callus cultures of bean (Phaseolus), lettuce (Lactuca), carrot (Daucus) and pepper (Capsicum). Laminaribiose is the major product. Lichenin and oat glucan were not attacked by these laminarinases.