Carbohydrate Binding Module 6 (CBM6); appended to glycoside hydrolase (GH) domains, including GH5 (cellulase). This family includes carbohydrate binding module 6 (CBM6) domains that are appended to several glycoside hydrolase (GH) domains, including GH5 (cellulase) and GH16, as well as to coagulation factor 5/8 carbohydrate-binding domains. CBM6s are non-catalytic carbohydrate binding domains that facilitate the strong binding of the GH catalytic modules with their dedicated, insoluble substrates. The CBM6s are appended to GHs that display a diversity of substrate specificities. For some members of this family information is available about the specific substrates of the appended GH domains. It includes the CBM domains of various enzymes involved in cell wall degradation including, an extracellular beta-1,3-glucanase from Lysobacter enzymogenes encoded by the gluC gene (its catalytic domain belongs to the GH16 family), the tandem CBM domains of Pseudomonas sp. PE2 beta-1,3(4)-glucanase A (its catalytic domain also belongs to GH16), and a family 6 CBM from Cellvibrio mixtus Endoglucanase 5A (CmCBM6) which binds to the beta1,4-beta1,3-mixed linked glucans lichenan, and barley beta-glucan, cello-oligosaccharides, insoluble forms of cellulose, the beta1,3-glucan laminarin, and xylooligosaccharides, and the CBM6 of Fibrobacter succinogenes S85 XynD xylanase, appended to a GH10 domain, and Cellvibrio japonicas Cel5G appended to a GH5 (cellulase) domain. GH5 (cellulase) family includes enzymes with several known activities such as endoglucanase, beta-mannanase, and xylanase, which are involved in the degradation of cellulose and xylans. GH16 family includes enzymes with lichenase, xyloglucan endotransglycosylase (XET), and beta-agarase activities. CBM6 is an unusual CBM as it represents a chimera of two distinct binding sites with different modes of binding: binding site I within the loop regions and binding site II on the concave face of the beta-sandwich fold. For CmCBM6 it has been shown that these two binding sites have different ligand specificities.

Alginate lyase. This family contains several bacterial alginate lyase proteins. Alginate is a family of 1-4-linked copolymers of beta -D-mannuronic acid (M) and alpha -L-guluronic acid (G). It is produced by brown algae and by some bacteria belonging to the genera Azotobacter and Pseudomonas. Alginate lyases catalyze the depolymerization of alginates by beta -elimination, generating a molecule containing 4-deoxy-L-erythro-hex-4-enepyranosyluronate at the nonreducing end. This family adopts an all alpha fold.

Carbohydrate Binding Module 6 (CBM6); appended mainly to glycoside hydrolase (GH) family 16 alpha- and beta agarases. This family includes carbohydrate binding module 6 (CBM6) domains that are appended mainly to glycoside hydrolase (GH) family 16 agarases. These CBM6s are non-catalytic carbohydrate binding domains that facilitate the activity of alpha- and beta-agarase catalytic modules which are involved in the hydrolysis of 1,4-beta-D-galactosidic linkages. These CBM6s bind specifically to the non-reducing end of agarose chains, recognizing only the first repeat of the disaccharide, and directing the appended catalytic modules to areas of the plant cell wall attacked by beta-agarases. CBM6 is an unusual CBM as it represents a chimera of two distinct binding sites with different modes of binding: binding site I within the loop regions and binding site II on the concave face of the beta-sandwich fold. This family includes three tandem CBM6s from the Saccharophagus degradans agarase Aga86E, and three tandem CBM6s from Vibrio sp. strain PO-303 AgaA; in both these proteins these are appended to a GH16 domain. Vibrio AgaA also contains a Big-2-like protein-protein interaction domain. This family also includes two tandem CBM6s from an endo-type beta-agarase from a deep-sea Microbulbifer-like isolate, which are appended to a GH16 domain, and two of three CBM6s of Alteromonas agarilytica AgaA alpha-agarase, which are appended to a GH96 domain.