2WW2: Structure Of The Family Gh92 Inverting Mannosidase Bt2199 From Bacteroides Thetaiotaomicron Vpi-5482

Citation:
Abstract
Colonic bacteria, exemplified by Bacteroides thetaiotaomicron, play a key role in maintaining human health by harnessing large families of glycoside hydrolases (GHs) to exploit dietary polysaccharides and host glycans as nutrients. Such GH family expansion is exemplified by the 23 family GH92 glycosidases encoded by the B. thetaiotaomicron genome. Here we show that these are alpha-mannosidases that act via a single displacement mechanism to utilize host N-glycans. The three-dimensional structure of two GH92 mannosidases defines a family of two-domain proteins in which the catalytic center is located at the domain interface, providing acid (glutamate) and base (aspartate) assistance to hydrolysis in a Ca(2+)-dependent manner. The three-dimensional structures of the GH92s in complex with inhibitors provide insight into the specificity, mechanism and conformational itinerary of catalysis. Ca(2+) plays a key catalytic role in helping distort the mannoside away from its ground-state (4)C(1) chair conformation toward the transition state.
PDB ID: 2WW2Download
MMDB ID: 79039
PDB Deposition Date: 2009/10/21
Updated in MMDB: 2009/12
Experimental Method:
x-ray diffraction
Resolution: 1.9  Å
Source Organism:
Similar Structures:
Biological Unit for 2WW2: trimeric; determined by author and by software (PISA)
Molecular Components in 2WW2
Label Count Molecule
Proteins (3 molecules)
3
Alpha-1,2-mannosidase
Molecule annotation
Chemicals (20 molecules)
1
1
2
4
3
14
4
1
* Click molecule labels to explore molecular sequence information.

Citing MMDB
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