Lichenase (EC 3.2.1.73), also known as licheninase or 1,3-1,4 ꞵ-D-glucanase, is an enzyme that hydrolyzes the β-1,4 glycosidic bond next to the β-1,3 bond in the polysaccharides lichenin and β-glucan. These polysaccharides are found in the cell walls of lichens and grains, respectively. In Bacillus species, lichenase is produced by the licA gene. Lichenase is a hydrolase, which means it uses water to cleave bonds. Specifically, lichenase is a glycosidase, or an enzyme that hydrolyzes O- and S-glycosyl compounds.