Has endoglucanase activity on substrates containing beta-1,4 glycosidic bonds, like in carboxymethylcellulose (CMC), hydroxyethylcellulose (HEC) and beta-glucan. Involved in the degradation of complex natural cellulosic substrates (By similarity). Endohydrolysis of (1->4)-beta-D-glucosidic linkages in cellulose, lichenin and cereal beta-D-glucans. Has a modular structure: an endo-beta-1,4-glucanase catalytic module at the N-terminus, a linker rich in serines and threonines, and a C-terminal carbohydrate-binding module (CBM). The genes for catalytic modules and CBMs seem to have evolved separately and have been linked by gene fusion. Belongs to the glycosyl hydrolase 61 family.