spacer
spacer

PDBsum entry 3vil

Go to PDB code: 
protein ligands metals links
Hydrolase PDB id
3vil
Jmol
Contents
Protein chain
472 a.a.
Ligands
SA0
SA9
EDO
Metals
_CL ×2
_NA
Waters ×669
PDB id:
3vil
Name: Hydrolase
Title: Crystal structure of beta-glucosidase from termite neotermes koshunensis in complex with salicin
Structure: Beta-glucosidase. Chain: a. Engineered: yes. Mutation: yes
Source: Neotermes koshunensis. Organism_taxid: 60586. Gene: nkbg. Expressed in: escherichia coli. Expression_system_taxid: 562.
Resolution:
1.15Å     R-factor:   0.129     R-free:   0.154
Authors: W.Y.Jeng,C.I.Liu,A.H.J.Wang
Key ref: W.Y.Jeng et al. (2012). High-resolution structures of Neotermes koshunensis β-glucosidase mutants provide insights into the catalytic mechanism and the synthesis of glucoconjugates. Acta Crystallogr D Biol Crystallogr, 68, 829-838. PubMed id: 22751668
Date:
03-Oct-11     Release date:   04-Jul-12    
PROCHECK
Go to PROCHECK summary
 Headers
 References

Protein chain
Pfam   ArchSchema ?
Q8T0W7  (Q8T0W7_9NEOP) -  Beta-glucosidase
Seq:
Struc:
498 a.a.
472 a.a.*
Key:    PfamA domain  Secondary structure  CATH domain
* PDB and UniProt seqs differ at 1 residue position (black cross)

 Enzyme reactions 
   Enzyme class: E.C.3.2.1.21  - Beta-glucosidase.
[IntEnz]   [ExPASy]   [KEGG]   [BRENDA]
      Reaction: Hydrolysis of terminal, non-reducing beta-D-glucose residues with release of beta-D-glucose.
 Gene Ontology (GO) functional annotation 
  GO annot!
  Biological process     metabolic process   2 terms 
  Biochemical function     hydrolase activity     4 terms  

 

 
Acta Crystallogr D Biol Crystallogr 68:829-838 (2012)
PubMed id: 22751668  
 
 
High-resolution structures of Neotermes koshunensis β-glucosidase mutants provide insights into the catalytic mechanism and the synthesis of glucoconjugates.
W.Y.Jeng, N.C.Wang, C.T.Lin, W.J.Chang, C.I.Liu, A.H.Wang.
 
  ABSTRACT  
 
NkBgl, a β-glucosidase from Neotermes koshunensis, is a β-retaining glycosyl hydrolase family 1 enzyme that cleaves β-glucosidic linkages in disaccharide or glucose-substituted molecules. β-Glucosidases have been widely used in several applications. For example, mutagenesis of the attacking nucleophile in β-glucosidase has been conducted to convert it into a glycosynthase for the synthesis of oligosaccharides. Here, several high-resolution structures of wild-type or mutated NkBgl in complex with different ligand molecules are reported. In the wild-type NkBgl structures it was found that glucose-like glucosidase inhibitors bind to the glycone-binding pocket, allowing the buffer molecule HEPES to remain in the aglycone-binding pocket. In the crystal structures of NkBgl E193A, E193S and E193D mutants Glu193 not only acts as the catalytic acid/base but also plays an important role in controlling substrate entry and product release. Furthermore, in crystal structures of the NkBgl E193D mutant it was found that new glucoconjugates were generated by the conjugation of glucose (hydrolyzed product) and HEPES/EPPS/opipramol (buffer components). Based on the wild-type and E193D-mutant structures of NkBgl, the glucosidic bond of cellobiose or salicin was hydrolyzed and a new bond was subsequently formed between glucose and HEPES/EPPS/opipramol to generate new glucopyranosidic products through the transglycosylation reaction in the NkBgl E193D mutant. This finding highlights an innovative way to further improve β-glucosidases for the enzymatic synthesis of oligosaccharides.