Carbohydrate Binding Module 6 (CBM6) and CBM35_like superfamily
Carbohydrate binding module family 6 (CBM6, family 6 CBM), also known as cellulose binding domain family VI (CBD VI), and related CBMs (CBM35 and CBM36). These are non-catalytic carbohydrate binding domains found in a range of enzymes that display activities against a diverse range of carbohydrate targets, including mannan, xylan, beta-glucans, cellulose, agarose, and arabinans. These domains facilitate the strong binding of the appended catalytic modules to their dedicated, insoluble substrates. Many of these CBMs are associated with glycoside hydrolase (GH) domains. 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. CBM36s are calcium-dependent xylan binding domains. CBM35s display conserved specificity through extensive sequence similarity, but divergent function through their appended catalytic modules. This alignment model also contains the C-terminal domains of bacterial insecticidal toxins, where they may be involved in determining insect specificity through carbohydrate binding functionality.
Jiyao W et al.(2023). "The conserved domain database in 2023.",