4AD0

Structure of the GH99 endo-alpha-mannosidase from Bacteriodes thetaiotaomicron in complex with BIS-TRIS-Propane


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.09 Å
  • R-Value Free: 0.237 
  • R-Value Work: 0.181 
  • R-Value Observed: 0.184 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Structural and Mechanistic Insight Into N-Glycan Processing by Endo-Alpha-Mannosidase.

Thompson, A.J.Williams, R.J.Hakki, Z.Alonzi, D.S.Wennekes, T.Gloster, T.M.Songsrirote, K.Thomas-Oates, J.E.Wrodnigg, T.M.Spreitz, J.Stutz, A.E.Butters, T.D.Williams, S.J.Davies, G.J.

(2012) Proc Natl Acad Sci U S A 109: 781

  • DOI: 10.1073/pnas.1111482109
  • Primary Citation of Related Structures:  
    4ACY, 4ACZ, 4AD0, 4AD1, 4AD2, 4AD3, 4AD4, 4AD5

  • PubMed Abstract: 
  • N-linked glycans play key roles in protein folding, stability, and function. Biosynthetic modification of N-linked glycans, within the endoplasmic reticulum, features sequential trimming and readornment steps. One unusual enzyme, endo-α-mannosidase, cleaves mannoside linkages internally within an N-linked glycan chain, short circuiting the classical N-glycan biosynthetic pathway ...

    N-linked glycans play key roles in protein folding, stability, and function. Biosynthetic modification of N-linked glycans, within the endoplasmic reticulum, features sequential trimming and readornment steps. One unusual enzyme, endo-α-mannosidase, cleaves mannoside linkages internally within an N-linked glycan chain, short circuiting the classical N-glycan biosynthetic pathway. Here, using two bacterial orthologs, we present the first structural and mechanistic dissection of endo-α-mannosidase. Structures solved at resolutions 1.7-2.1 Å reveal a (β/α)(8) barrel fold in which the catalytic center is present in a long substrate-binding groove, consistent with cleavage within the N-glycan chain. Enzymatic cleavage of authentic Glc(1/3)Man(9)GlcNAc(2) yields Glc(1/3)-Man. Using the bespoke substrate α-Glc-1,3-α-Man fluoride, the enzyme was shown to act with retention of anomeric configuration. Complexes with the established endo-α-mannosidase inhibitor α-Glc-1,3-deoxymannonojirimycin and a newly developed inhibitor, α-Glc-1,3-isofagomine, and with the reducing-end product α-1,2-mannobiose structurally define the -2 to +2 subsites of the enzyme. These structural and mechanistic data provide a foundation upon which to develop new enzyme inhibitors targeting the hijacking of N-glycan synthesis in viral disease and cancer.


    Organizational Affiliation

    Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
ENDO-ALPHA-MANNOSIDASEA, B, C, D382Bacteroides thetaiotaomicron VPI-5482Mutation(s): 0 
Gene Names: BT_3862
EC: 3.2.1.130
UniProt
Find proteins for Q8A109 (Bacteroides thetaiotaomicron (strain ATCC 29148 / DSM 2079 / JCM 5827 / CCUG 10774 / NCTC 10582 / VPI-5482 / E50))
Explore Q8A109 
Go to UniProtKB:  Q8A109
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ8A109
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
B3P
Query on B3P

Download Ideal Coordinates CCD File 
E [auth A],
G [auth B],
I [auth C],
K [auth D]
2-[3-(2-HYDROXY-1,1-DIHYDROXYMETHYL-ETHYLAMINO)-PROPYLAMINO]-2-HYDROXYMETHYL-PROPANE-1,3-DIOL
C11 H26 N2 O6
HHKZCCWKTZRCCL-UHFFFAOYSA-N
 Ligand Interaction
GOL
Query on GOL

Download Ideal Coordinates CCD File 
F [auth A],
H [auth B],
J [auth C],
L [auth D]
GLYCEROL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.09 Å
  • R-Value Free: 0.237 
  • R-Value Work: 0.181 
  • R-Value Observed: 0.184 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 65.993α = 90
b = 168.428β = 117.08
c = 72.433γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
HKL-2000data reduction
SCALEPACKdata scaling
MOLREPphasing

Structure Validation

View Full Validation Report



Entry History 

Revision History  (Full details and data files)

  • Version 1.0: 2012-02-01
    Type: Initial release
  • Version 1.1: 2012-02-29
    Changes: Other