Cellulose consists of polymer chains of -1,4, linked glucose units and its enzymatic degradation .
is initiated by endo--1,4-glucanase (EC 3.1.2.4), which breaks cellulose chains into smaller units, and cellobiohydrolase (EC 3.1.2.91), which cleaves the dimer cellobiose (two -1,4 linked glucose units) from the reducing ‘ends’ of the molecules.