2J72: Alpha-Glucan Recognition By A Family 41 Carbohydrate- Binding Module From Thermotoga Maritima Pullulanase Pula

Starch recognition by carbohydrate-binding modules (CBMs) is important for the activity of starch-degrading enzymes. The N-terminal family 41 CBM, TmCBM41 (from pullulanase PulA secreted by Thermotoga maritima) was shown to have alpha-glucan binding activity with specificity for alpha-1,4-glucans but was able to tolerate the alpha-1,6-linkages found roughly every three or four glucose units in pullulan. Using X-ray crystallography, the structures were solved for TmCBM41 in an uncomplexed form and in complex with maltotetraose and 6(3)-alpha-D-glucosyl-maltotriose (GM3). Ligand binding was facilitated by stacking interactions between the alpha-faces of the glucose residues and two tryptophan side-chains in the two main subsites of the carbohydrate-binding site. Overall, this mode of starch binding is quite well conserved by other starch-binding modules. The structure in complex with GM3 revealed a third binding subsite with the flexibility to accommodate an alpha-1,4- or an alpha-1,6-linked glucose.
PDB ID: 2J72Download
MMDB ID: 64240
PDB Deposition Date: 2006/10/5
Updated in MMDB: 2012/10
Experimental Method:
x-ray diffraction
Resolution: 1.49  Å
Source Organism:
Similar Structures:
Biological Unit for 2J72: dimeric; determined by author and by software (PQS)
Molecular Components in 2J72
Label Count Molecule
Proteins (2 molecules)
Pullulanase(Gene symbol: TM1845)
Molecule annotation
Chemicals (8 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB