Carbohydrates, classification cellulose

Tomme P, Warren AJ, Miller Jr. RC, KUburn DG, GUkes NR (1995) Cellulose-binding domains classification and properties. In Saddler JN, Penner MH (eds) Enzymatic degradation of insoluble carbohydrates. American Chemical Society, Washington, DC, pl42 Irwin D, Walker L, Spezio M, Wilson D (1993) Biotech Bioengin 42 1002... 

Many glycosidases which attack insoluble or partly soluble polysaccharides have a modular construction, in which catalytic domains and carbohydrate binding modules (CBMs) are produced in the same polypeptide. Although there may be occasional exceptions, the main function of these domains appears to be to increase the local concentration of enzyme by loosely absorbing the enzyme to the substrate. CBMs have been classified into families on the basis of amino acid sequence, like the catalytic domains and are on CAZy, the continuously updated website in summer 2007 there were 49 families. Early work had concentrated on the cellulose binding domains (CBDs) previous classifications had referred to CBM (or CBD) Types and used Roman numerals and, to concur with this usage, CBM Families 1-13 are the same as CBM Types 1-XIII. 

A recent classification (1 ) describes the pectic polysaccharides as those polymers found in covalent association with galactu-ronosyl-containing polysaccharides. The hemicelluloses are those carbohydrate polymers which are noncovalently associated with cellulose. Diverse categories of pectic polysaccharides occur not only among plant sources, but among tissues in a given source. 

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