Traditionally, cellulase (endo-1,4-b-glucanase) has been assayed using reducing-sugar procedures with cellulose, soluble cellulose derivatives (e.g. CM-cellulose) or mixed-linkage b-glucan as substrates. More recently, soluble, dyed polysaccharides and dyed and cross-linked polysaccharides (insoluble, gelatinous) have found widespread use. None of these substrates or assay procedures readily lends themselves to automation. To satisfy this need, a range of end-blocked nitrophenyl-cello-oligosaccharides have been produced and evaluated in the assay of cellulase. The assay procedures may or may not include an ancilliary b-glucosidase. Substrates include 2-chloro-4-nitrophenyl-4,6-O-benzylidine- b-D-cellobioside, -cellotrioside and -cellotetraoside, and the ancilliary enzyme used is a recombinant thermostable b-glucosidase. A schematic representation of the assay is shown below.
McCleary B.V., Mangan D.P. -Patent pending.
