Mighty's World Health Site

CBHs cellobiohydrolases exoglucanases

• How to Reverse Diabetes Naturally
• Human Anatomy And Physiology Study Course
• PCOS and Insulin Resistance - What You Need to Know About

Like endoglucanases, the CBHs are highly active on amorphous and swollen celluloses, but degrade crystalline cellulose and cello-oligosaccharides rather poorly (Wood and Bhat, 1988). These enzymes are specific for P-1,4 linkages of the cellulose chain, but are inactive on cellobiose, CM- and hydroxyethyl-celluloses. In general, CBHs attack cellulose chains from the non-reducing end and release cellobiose (Wood et al., 1988). Recent kinetic studies and high-resolution structural data confirmed that there are two classes of CBHs (Barr et al., 1996). The class one enzymes (e.g. CBH I from T. reesei and two exoglucanases E4 and E6 from T. fusca) hydrolyse the cellulose chain preferentially from the reducing end, while class two CBHs (e.g. CBH II from T. reesei and E3 from T. fusca) release cellobiose specifically from the non-reducing end (Barr et al., 1996; Teeri, 1997).