Phospho-beta-D-glucosidase that seems to be involved in the degradation of glucomannan. Is also capable of hydrolyzing aryl-phospho-beta-D-glucosides, although very weakly, and plays only a minor role, if any, in the degradation of these substrates in vivo. 6-phospho-beta-D-glucosyl-(1->4)-D-glucose + H2O = D-glucose + D-glucose 6-phosphate Expressed at only a very low level in exponential-phase cells and germinating spores, but is expressed at a higher levels upon entry into the stationary phase of growth. Up-regulated by konjac glucomannan and by cellobiose and mannobiose, the possible degradation products of glucomannan. Repressed by glucose via the carbon catabolite repression system. Also repressed by GmuR. Is not induced by aryl-beta-D-glucosides such as arbutin or salicin. Belongs to the glycosyl hydrolase 1 family.