2zew
Family 16 Cabohydrate Binding Domain Module 1
OverviewOverview
Enzymes that hydrolyze complex polysaccharides into simple sugars are modular in architecture and consist of single or multiple catalytic domains fused to targeting modules called carbohydrate binding modules (CBMs). CBMs bind to their ligands with high affinity, and increase the efficiency of the catalytic components by targeting the enzymes to its substrate. Here, we utilized a multi-disciplinary approach to characterize each of the two family 16 carbohydrate binding domain component of the highly active mannanase from the thermophile T. polysaccharolyticum. These represent the first crystal structures of family 16 CBMs. Calorimetric analysis show that while these CBMs demonstrate high specificity towards ss-1,4 linked sugars, they can engage both cello- and manno-polysaccharides. In order to elucidate the molecular basis for this specificity and selectivity, we have determined high resolution crystal structures of each of the two carbohydrate binding modules, as well as of binary complexes of CBM16-1 bound to either mannopentaose or cellopentaose. These results provide detailed molecular insights into ligand recognition and yield a framework for rational engineering experiments designed to expand the natural repertoire of these targeting modules.
About this StructureAbout this Structure
2ZEW is a Single protein structure of sequence from Thermoanaerobacterium polysaccharolyticum. Full crystallographic information is available from OCA.
ReferenceReference
Molecular basis for the selectivity and specificity of ligand recognition by the family 16 carbohydrate binding modules from thermoanaerobacterium polysaccharolyticum manA., Bae B, Ohene-Adjei S, Kocherginskaya S, Mackie RI, Spies MA, Cann IK, Nair SK, J Biol Chem. 2007 Nov 29;. PMID:18025086 Page seeded by OCA on Thu May 22 22:34:31 2008