Beta-L-arabinofuranosidase, GH127. One member of this family, from Bidobacterium longicum, UniProtKB:E8MGH8, has been characterized as an unusual beta-L-arabinofuranosidase enzyme, EC:3.2.1.185. It rleases l-arabinose from the l-arabinofuranose (Araf)-beta1,2-Araf disaccharide and also transglycosylates 1-alkanols with retention of the anomeric configuration. Terminal beta-l-arabinofuranosyl residues have been found in arabinogalactan proteins from a mumber of different plantt species. beta-l-Arabinofuranosyl linkages with 1-4 arabinofuranosides are also found in the sugar chains of extensin and solanaceous lectins, hydroxyproline (Hyp)2-rich glycoproteins that are widely observed in plant cell wall fractions. The critical residue for catalytic activity is Glu-338, in a ET/SCAS sequence context.
Type I dockerin repeat domain. Bacterial cohesin domains bind to a complementary protein domain named dockerin, and this interaction is required for the formation of the cellulosome, a cellulose-degrading complex. The cellulosome consists of scaffoldin, a noncatalytic scaffolding polypeptide, that comprises repeating cohesion modules and a single carbohydrate-binding module (CBM). Specific calcium-dependent interactions between cohesins and dockerins appear to be essential for cellulosome assembly. This subfamily represents type I dockerins, which are responsible for anchoring a variety of enzymatic domains to the complex.
Domain of Unknown Function (DUF1080). This family has structural similarity to an endo-1,3-1,4-beta glucanase belonging to glycoside hydrolase family 16. However, the structure surrounding the active site differs from that of the endo-1,3-1,4-beta glucanase.