Hydrolysis of cellobiose from the reducing end of xyloglucans consisting of a (1→4)-β-linked glucan carrying α-D-xylosyl groups on O-6 of the glucose residues. To be a substrate, the first residue must be unsubstituted, the second residue may bear a xylosyl group, whether further glycosylated or not, and the third residue, which becomes the new terminus by the action of the enzyme, is preferably xylosylated, but this xylose residue must not be further substituted.
oligoxyloglucan reducing-end cellobiohydrolase
The enzyme is found in the fungus Geotrichum sp. M128. The substrate is a hemicellulose found in plant cell walls.
Yaoi, K. and Mitsuishi, Y. Purification, characterization, cloning, and expression of a novel xyloglucan-specific glycosidase, oligoxyloglucan reducing end-specific cellobiohydrolase. J. Biol. Chem.277 (2002) 48276–48281. [DOI] [PMID: 12374797]