Secreted manganese dependent endoglucanase that acts by cleaving the beta-1,4-glucose linkage (PubMed:26173955). Exhibits high activity toward carboxymethyl-cellulose (CMC), barley glucan, and glucomannan (PubMed:26173955). Displays low activity on larminarin and xyloglucan but does not hydrolyze hemicellulose substrates such as birchwood xylan, arabinoxylan, and arabinan (PubMed:26173955). Endohydrolysis of (1->4)-beta-D-glucosidic linkages in cellulose, lichenin and cereal beta-D-glucans. Optimum pH is 4.5-6.0. Optimum temperature is 50-60 degrees Celsius. Displays a synergistic action with cellobiase resulting in an increase of the saccharification of NaOH-pretreated barley straw, promising a further use of this enzyme in biomass saccharification purpose (PubMed:26173955). Belongs to the glycosyl hydrolase 5 (cellulase A) family.