4JIE

Structural analysis and insights into glycon specificity of the rice GH1 Os7BGlu26 beta-D-mannosidase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.45 Å
  • R-Value Free: 0.195 
  • R-Value Work: 0.153 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural analysis and insights into the glycon specificity of the rice GH1 Os7BGlu26 beta-D-mannosidase

Tankrathok, A.Iglesias-Fernandez, J.Luang, S.Robinson, R.C.Kimura, A.Rovira, C.Hrmova, M.Ketudat Cairns, J.R.

(2013) Acta Crystallogr.,Sect.D 69: 2124-2135

  • DOI: 10.1107/S0907444913020568
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Rice Os7BGlu26 is a GH1 family glycoside hydrolase with a threefold higher kcat/Km value for 4-nitrophenyl β-D-mannoside (4NPMan) compared with 4-nitrophenyl β-D-glucoside (4NPGlc). To investigate its selectivity for β-D-mannoside and β-D-glucoside s ...

    Rice Os7BGlu26 is a GH1 family glycoside hydrolase with a threefold higher kcat/Km value for 4-nitrophenyl β-D-mannoside (4NPMan) compared with 4-nitrophenyl β-D-glucoside (4NPGlc). To investigate its selectivity for β-D-mannoside and β-D-glucoside substrates, the structures of apo Os7BGlu26 at a resolution of 2.20 Å and of Os7BGlu26 with mannose at a resolution of 2.45 Å were elucidated from isomorphous crystals in space group P212121. The (β/α)8-barrel structure is similar to other GH1 family structures, but with a narrower active-site cleft. The Os7BGlu26 structure with D-mannose corresponds to a product complex, with β-D-mannose in the (1)S5 skew-boat conformation. Docking of the (1)S3, (1)S5, (2)SO and (3)S1 pyranose-ring conformations of 4NPMan and 4NPGlc substrates into the active site of Os7BGlu26 indicated that the lowest energies were in the (1)S5 and (1)S3 skew-boat conformations. Comparison of these docked conformers with other rice GH1 structures revealed differences in the residues interacting with the catalytic acid/base between enzymes with and without β-D-mannosidase activity. The mutation of Tyr134 to Trp in Os7BGlu26 resulted in similar kcat/Km values for 4NPMan and 4NPGlc, while mutation of Tyr134 to Phe resulted in a 37-fold higher kcat/Km for 4NPMan than 4NPGlc. Mutation of Cys182 to Thr decreased both the activity and the selectivity for β-D-mannoside. It was concluded that interactions with the catalytic acid/base play a significant role in glycon selection.


    Organizational Affiliation

    School of Biochemistry, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Beta-mannosidase/beta-glucosidase
A
503Oryza sativa subsp. indicaMutation(s): 0 
Find proteins for A2YPH1 (Oryza sativa subsp. indica)
Go to UniProtKB:  A2YPH1
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
EPE
Query on EPE

Download SDF File 
Download CCD File 
A
4-(2-HYDROXYETHYL)-1-PIPERAZINE ETHANESULFONIC ACID
HEPES
C8 H18 N2 O4 S
JKMHFZQWWAIEOD-UHFFFAOYSA-N
 Ligand Interaction
GOL
Query on GOL

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Download CCD File 
A
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
BMA
Query on BMA

Download SDF File 
Download CCD File 
A
BETA-D-MANNOSE
C6 H12 O6
WQZGKKKJIJFFOK-RWOPYEJCSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.45 Å
  • R-Value Free: 0.195 
  • R-Value Work: 0.153 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 68.010α = 90.00
b = 73.624β = 90.00
c = 133.984γ = 90.00
Software Package:
Software NamePurpose
MOLREPphasing
HKL-2000data scaling
ADSCdata collection
REFMACrefinement
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-10-09
    Type: Initial release
  • Version 1.1: 2014-04-23
    Type: Database references