CATH Classification

Domain Context

CATH Clusters

Superfamily Endo-1,4-beta-glucanase f. Domain 2
Functional Family

Enzyme Information

3.2.1.176
Cellulose 1,4-beta-cellobiosidase (reducing end).
based on mapping to UniProt P0C2S5
Hydrolysis of (1->4)-beta-D-glucosidic linkages in cellulose and similar substrates, releasing cellobiose from the reducing ends of the chains.
-!- Some exocellulases, most of which belong to the glycoside hydrolase family 48 (GH48), act at the reducing ends of cellulose and similar substrates. -!- The CelS enzyme from Clostridium thermocellum is the most abundant subunit of the cellulosome formed by the organism. -!- It liberates cellobiose units from the reducing end by hydrolysis of the glycosidic bond, employing an inverting reaction mechanism. -!- Different from EC 3.2.1.91, which attacks cellulose from the non- reducing end.

UniProtKB Entries (1)

P0C2S5
GUNS_CLOTM
Hungateiclostridium thermocellum
Cellulose 1,4-beta-cellobiosidase (reducing end) CelS

PDB Structure

PDB 1L1Y
External Links
Method X-RAY DIFFRACTION
Organism Escherichia
Primary Citation
The crystal structure and catalytic mechanism of cellobiohydrolase CelS, the major enzymatic component of the Clostridium thermocellum Cellulosome.
Guimaraes, B.G., Souchon, H., Lytle, B.L., David Wu, J.H., Alzari, P.M.
J.Mol.Biol.