Glycoside hydrolase, family 16, active site <p>O-Glycosyl hydrolases <db_xref db="EC" dbkey="3.2.1."/> are a widespread group of enzymes that hydrolyse the glycosidic bond between two or more carbohydrates, or between a carbohydrate and a non-carbohydrate moiety. A classification system for glycosyl hydrolases, based on sequence similarity, has led to the definition of 85 different families [<cite idref="PUB00004870"/>, <cite idref="PUB00005266"/>]. This classification is available on the CAZy (CArbohydrate-Active EnZymes) web site.</p><p>Glycoside hydrolase family 16 <db_xref db="CAZY" dbkey="GH16"/> comprises enzymes with a number of known activities; lichenase (<db_xref db="EC" dbkey="3.2.1.73"/>); xyloglucan xyloglucosyltransferase (<db_xref db="EC" dbkey="2.4.1.207"/>); agarase (<db_xref db="EC" dbkey="3.2.1.81"/>); kappa-carrageenase (<db_xref db="EC" dbkey="3.2.1.83"/>); endo-beta-1,3-glucanase (<db_xref db="EC" dbkey="3.2.1.39"/>); endo-beta-1,3-1,4-glucanase (<db_xref db="EC" dbkey="3.2.1.6"/>); endo-beta-galactosidase (<db_xref db="EC" dbkey="3.2.1.103"/>). Two closely clustered and conserved glutamates, which are part of this signature, have been shown to be involved in the catalytic activity of <taxon tax_id="1402">Bacillus licheniformis</taxon>.</p>