6IX2

Structure of the A214C/A250I mutant of an epoxide hydrolase from Aspergillus usamii E001 (AuEH2) at 1.48 Angstroms resolution

• PDB DOI: https://doi.org/10.2210/pdb6IX2/pdb

• Classification: HYDROLASE
• Organism(s): Aspergillus usamii
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): Yes 


• Deposited: 2018-12-09 Released: 2019-12-11 
• Deposition Author(s): Hu, D., Hu, B.C., Hou, X.D., Rao, Y.J., Wu, M.C.
• Funding Organization(s): National Natural Science Foundation of China

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.48 Å
• R-Value Free: 0.178 
• R-Value Work: 0.159 
• R-Value Observed: 0.160 

Literature

Structure-Guided Regulation in the Enantioselectivity of an Epoxide Hydrolase to Produce Enantiomeric Monosubstituted Epoxides and Vicinal Diols via Kinetic Resolution.

Hu, D., Hu, B.C., Hou, X.D., Zhang, D., Lei, Y.Q., Rao, Y.J., Wu, M.C.

(2022) Org Lett 24: 1757-1761

• PubMed: 35229602 
• DOI: https://doi.org/10.1021/acs.orglett.1c04348
• Primary Citation of Related Structures:  
  6IX2


• PubMed Abstract: 
  

  Structure-guided microtuning of an Aspergillus usamii epoxide hydrolase was executed. One mutant, A214C/A250I, displayed a 12.6-fold enhanced enantiomeric ratio ( E = 202) toward rac -styrene oxide, achieving its nearly perfect kinetic resolution at 0.8 M in pure water or 1.6 M in n -hexanol/water. Several other beneficial mutants also displayed significantly improved E values, offering promising biocatalysts to access 19 structurally diverse chiral monosubstituted epoxides (97.1 - ≥ 99% ee _s ) and vicinal diols (56.2-98.0% ee _p ) with high yields.

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Organizational Affiliation: 

Wuxi School of Medicine, Jiangnan University, Wuxi 214122, P.R. China.

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly Evidence: native gel electrophoresis

Macromolecule Content

• Total Structure Weight: 97.23 kDa 
• Atom Count: 7,239 
• Modelled Residue Count: 765 
• Deposited Residue Count: 862 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Microsomal epoxide hyddrolase	A, B	431	Aspergillus usamii	Mutation(s): 2  Gene Names: EH2 EC: 3.3.2.9
UniProt
Find proteins for T2B4K5 (Aspergillus usamii) Explore T2B4K5  Go to UniProtKB:  T2B4K5

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
GOL	C [auth A]	GLYCEROL C3 H8 O3 PEDCQBHIVMGVHV-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.48 Å
• R-Value Free: 0.178 
• R-Value Work: 0.159 
• R-Value Observed: 0.160 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 57.365	α = 90
b = 51.922	β = 90.97
c = 133.488	γ = 90

Software Package:

Software Name	Purpose
PHENIX	refinement
HKL-3000	data scaling
HKL-3000	data reduction
AMPLE	phasing
PDB_EXTRACT	data extraction

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2019-12-11 
Deposition Author(s): Hu, D., Hu, B.C., Hou, X.D., Rao, Y.J., Wu, M.C.

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Funding Organization	Location	Grant Number
National Natural Science Foundation of China	China	21676117

Revision History  

• Version 1.0: 2019-12-11
  Type: Initial release
  
• Version 1.1: 2022-11-02
  Changes: Database references
• Version 1.2: 2023-11-29
  Changes: Data collection, Refinement description