Glycosidases cellulase

In contrast to cellulases, the hemicellulases encompass a much broader suite of activities. In addition to analogue versions of endo-, exo-, and glycosidase cellulase activities, multiple debranching activities are needed to handle the high complexity of the heterogeneous hemicelluloses (Table 33.3). The varied backbone composition of hemicelluloses also adds complexity. Xylans, xyloglucans, man-nans, and numerous other minor polysaccharide chains form the backbone for different hemicelluloses. 

Glycosidases (cellulases and amylases from As-pergillus niger) in combination with proteinases are recommended for removal of shells from shrimp. The shells are loosened and then washed off in a stream of water. 

Hydrolases Glycosidase (cellulase, amylase, chitinase, hyaluronidase), lipase, peptidase, protease Polysaccharides, polyesters, polyamides, polycarbonates, poly( amino acid)s... 

Kobayashi and coworkers proposed a mechanism for the enzymatic polymerization of 3-D-cellobiosyl fluoride with cellulase following the general accepted mechanism for glycosidase-catalyzed synthesis of glycosides. 

Table 10-3. Production of thermoactive cellulases (exoglucanase, B-glycosidase), xylanases (endoxylanase) and chitinase by some representatives of extreme thermophilic and hyperthermophilic Archaea and Bacteria. 

The following companies offer screening set/kits for quick enzyme selection (Table 20-2). While some companies include only industrial scale enzymes, others contain enzymes only available at lab quantities. Diversa Co. offers an enzyme subscription program for lipases, esterases, nitrilases, cellulases, glycosidases, phosphatases, and transaminases (aminotransferases). 

Recent crystal structure studies confirm the presence of two fixed and opposed active-site carboxyl groups in nearly all glycosidases, including /3-galactosidase 77 cellulases 4 of families 6,7,9,10, and 45 56 80-88 xylanases 89-93 alpha-amylases 94-100 beta-amylase 101-102 and glucoamylase.1031048 Hev-amine, a chitinase from Hevea braziliensis. is exceptional in lacking a cat-... 

Fig. 2.8. Scaffold formation/disruption assays based on supramolecular self-assemblies. In this scheme, a cyanine is helicogenic. Molecular self-assembly of cyanine upon linear chiral polymer such as CMA, CMC, or HA results in a conformation transition of the polymer to adopt a super-helix structure. Scaffold disrupting glycosidases (hyaluronidase, amylase, cellulase) trigger fluorescence attenuation by disruption of the helical scaffold...

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