6RQK

Crystal structure of GH125 1,6-alpha-mannosidase from Clostridium perfringens in complex with mannoimidazole

• PDB DOI: https://doi.org/10.2210/pdb6RQK/pdb

• Classification: HYDROLASE
• Organism(s): Clostridium perfringens str. 13
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2019-05-16 Released: 2019-08-28 
• Deposition Author(s): Males, A., Davies, G.J.
• Funding Organization(s): Biotechnology and Biological Sciences Research Council

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.85 Å
• R-Value Free: 0.239 
• R-Value Work: 0.196 
• R-Value Observed: 0.198 

Literature

Distortion of mannoimidazole supports a B2,5boat transition state for the family GH125 alpha-1,6-mannosidase from Clostridium perfringens.

Males, A., Speciale, G., Williams, S.J., Davies, G.J.

(2019) Org Biomol Chem 17: 7863-7869

• PubMed: 31407758 
• DOI: https://doi.org/10.1039/c9ob01161g
• Primary Citation of Related Structures:  
  6RQK


• PubMed Abstract: 
  

  Enzyme transition-state mimics can act as powerful inhibitors and allow structural studies that report on the conformation of the transition-state. Here, mannoimidazole, a mimic of the transition state of mannosidase catalyzed hydrolysis of mannosides, is shown to bind in a B2,5 conformation on the Clostridium perfringens GH125 α-1,6-mannosidase, providing additional evidence of a OS2-B2,5-1S5 conformational itinerary for enzymes of this family.

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Organizational Affiliation: 

York Structural Biology Laboratory, Department of Chemistry, The University of York, YO10 5DD York, UK. [e-mail].

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Biological Assembly 2  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 2 assigned by authors.

Macromolecule Content

• Total Structure Weight: 102.52 kDa 
• Atom Count: 7,177 
• Modelled Residue Count: 849 
• Deposited Residue Count: 870 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Alpha-1,6-mannosidase	A, B	435	Clostridium perfringens str. 13	Mutation(s): 0  Gene Names: CPE0426
UniProt
Find proteins for Q8XNB2 (Clostridium perfringens (strain 13 / Type A)) Explore Q8XNB2  Go to UniProtKB:  Q8XNB2

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
MVL (Subject of Investigation/LOI)	C [auth A], D [auth A], E [auth B], F [auth B]	(5R,6R,7S,8R)-5-(HYDROXYMETHYL)-5,6,7,8-TETRAHYDROIMIDAZO[1,2-A]PYRIDINE-6,7,8-TRIOL C8 H12 N2 O4 RZRDQZQPTISYKY-JWXFUTCRSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
MVL	Binding MOAD:  6RQK	Kd: 1.60e+6 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.85 Å
• R-Value Free: 0.239 
• R-Value Work: 0.196 
• R-Value Observed: 0.198 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 55.479	α = 90
b = 43.048	β = 91.64
c = 169.616	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
xia2	data reduction
Aimless	data scaling
MOLREP	phasing

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2019-08-28 
Deposition Author(s): Males, A., Davies, G.J.

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Funding Organization	Location	Grant Number
Biotechnology and Biological Sciences Research Council	United Kingdom	BB/M011151/1

Revision History  

• Version 1.0: 2019-08-28
  Type: Initial release
  
• Version 1.1: 2019-09-11
  Changes: Data collection, Database references
• Version 1.2: 2024-01-24
  Changes: Data collection, Database references, Refinement description