1UWW: X-Ray Crystal Structure Of A Non-Crystalline Cellulose Specific Carbohydrate-Binding Module: Cbm28

Natural cellulose exists as a composite of different forms, which have historically been broadly characterized as "crystalline" or "amorphous". The recognition of both of these forms of cellulose by the carbohydrate-binding modules (CBM) of microbial glycoside hydrolases is central to natural and efficient biotechnological conversion of plant cell wall biomass. There is increasing evidence that, at least some, individual binding modules target distinct and different regions of non-crystalline "amorphous" cellulose. Competition experiments show that CBM28 modules do not compete with CBM17 modules when binding to non-crystalline cellulose. The structure of the BspCBM28 (http://afmb.cnrs-mrs.fr/CAZY/) module from the Bacillus sp. 1139 family GH5 endoglucanase, comprising a 191 amino acid protein, has therefore been determined at 1.4A resolution using single isomorphous replacement with anomalous scattering methods. The structure reveals a "beta-jelly roll" topology, with high degree of similarity to the structure of CBM17 domains. Sequence and structural conservation strongly suggests that these two families of domains have evolved through gene duplication and subsequent divergence. The ligand-binding site "topographies" of CBMs from families 28, 17 and 4 begins to shed light on the differential recognition of non-crystalline cellulose by multi-modular plant cell wall-degrading enzymes.
PDB ID: 1UWWDownload
MMDB ID: 27999
PDB Deposition Date: 2004/2/12
Updated in MMDB: 2012/10
Experimental Method:
x-ray diffraction
Resolution: 1.4  Å
Source Organism:
Similar Structures:
Biological Unit for 1UWW: dimeric; determined by author and by software (PQS)
Molecular Components in 1UWW
Label Count Molecule
Proteins (2 molecules)
Molecule annotation
Chemicals (6 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB