This carbohydrate binding domain is found at the N-terminal end of Glycoside hydrolase family 9 (GH9) from Acetivibrio thermocellus (Swiss:A3DD30). This protein contains GH9 and GH44 as catalytic modules (Pfam:PF00759 and Pfam:PF12891). It also presents a family 30 carbohydrate binding domain (CBM30), which displays affinity for beta-1,4-glucopolymers and plays a pivotal role in the function of of GH9, a typical processive endoglucanase. This domain adopts a beta-sandwich fold with two five-stranded beta-sheets [1].

1: Xyloglucan is recognized by carbohydrate-binding modules that interact with beta-glucan chains. Najmudin S, Guerreiro CI, Carvalho AL, Prates JA, Correia MA, Alves VD, Ferreira LM, Romao MJ, Gilbert HJ, Bolam DN, Fontes CM; J Biol Chem. 2006;281:8815-8828. PMID:16314409