4U1A

Crystal structure of human peroxisomal delta3,delta2, enoyl-CoA isomerase helix-10 deletion mutant (ISOB-ECI2)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.85 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.176 
  • R-Value Observed: 0.179 

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

Human Delta (3) , Delta (2) -enoyl-CoA isomerase, type 2: a structural enzymology study on the catalytic role of its ACBP domain and helix-10.

Onwukwe, G.U.Kursula, P.Koski, M.K.Schmitz, W.Wierenga, R.K.

(2015) FEBS J 282: 746-768

  • DOI: https://doi.org/10.1111/febs.13179
  • Primary Citation of Related Structures:  
    4U18, 4U19, 4U1A

  • PubMed Abstract: 

    The catalytic domain of the trimeric human Δ(3),Δ(2)-enoyl-CoA isomerase, type 2 (HsECI2), has the typical crotonase fold. In the active site of this fold two main chain NH groups form an oxyanion hole for binding the thioester oxygen of the 3E- or 3Z-enoyl-CoA substrate molecules. A catalytic glutamate is essential for the proton transfer between the substrate C2 and C4 atoms for forming the product 2E-enoyl-CoA, which is a key intermediate in the β-oxidation pathway. The active site is covered by the C-terminal helix-10. In HsECI2, the isomerase domain is extended at its N terminus by an acyl-CoA binding protein (ACBP) domain. Small angle X-ray scattering analysis of HsECI2 shows that the ACBP domain protrudes out of the central isomerase trimer. X-ray crystallography of the isomerase domain trimer identifies the active site geometry. A tunnel, shaped by loop-2 and extending from the catalytic site to bulk solvent, suggests a likely mode of binding of the fatty acyl chains. Calorimetry data show that the separately expressed ACBP and isomerase domains bind tightly to fatty acyl-CoA molecules. The truncated isomerase variant (without ACBP domain) has significant enoyl-CoA isomerase activity; however, the full-length isomerase is more efficient. Structural enzymological studies of helix-10 variants show the importance of this helix for efficient catalysis. Its hydrophobic side chains, together with residues from loop-2 and loop-4, complete a hydrophobic cluster that covers the active site, thereby fixing the thioester moiety in a mode of binding competent for efficient catalysis.


  • Organizational Affiliation

    Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Finland.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Enoyl-CoA delta isomerase 2
A, B, C
270Homo sapiensMutation(s): 0 
Gene Names: ECI2DRS1HCA88PECI
EC: 5.3.3.8
UniProt & NIH Common Fund Data Resources
Find proteins for O75521 (Homo sapiens)
Explore O75521 
Go to UniProtKB:  O75521
PHAROS:  O75521
GTEx:  ENSG00000198721 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupO75521
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.85 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.176 
  • R-Value Observed: 0.179 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 74.44α = 90
b = 95.34β = 90
c = 129.97γ = 90
Software Package:
Software NamePurpose
REFMACrefinement

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Biostruct-XGermanyN283570

Revision History  (Full details and data files)

  • Version 1.0: 2014-12-24
    Type: Initial release
  • Version 1.1: 2014-12-31
    Changes: Database references
  • Version 1.2: 2015-01-14
    Changes: Database references
  • Version 1.3: 2015-02-25
    Changes: Database references
  • Version 1.4: 2024-05-08
    Changes: Data collection, Database references, Refinement description