DOMON-like type 9 carbohydrate binding module of xylanases
Family 9 carbohydrate-binding modules (CBM9) play a role in the microbial degradation of cellulose and hemicellulose (materials found in plants). The domain has previously been called cellulose-binding domain. The polysaccharide binding sites of CBMs with available 3D structure have been found to be either flat surfaces with interactions formed by predominantly aromatic residues (tryptophan and tyrosine), or extended shallow grooves. The CBM9 domain frequently occurs in tandem repeats; members found in this subfamily typically co-occur with glycosyl hydrolase family 10 domains and are annotated as endo-1,4-beta-xylanases. CBM9 from Thermotoga maritima xylanase 10A is reported to have specificity for polysaccharide reducing ends.