8QDQ

Vitis vinifera dimeric 13S-lipoxygenase LOXA in the closed conformation


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.235 
  • R-Value Work: 0.199 
  • R-Value Observed: 0.201 

wwPDB Validation   3D Report Full Report


This is version 1.0 of the entry. See complete history


Literature

Vitis vinifera lipoxygenase LoxA is an allosteric dimer activated by lipidic surfaces.

Pilati, S.Wild, K.Gumiero, A.Holdermann, I.Hackmann, Y.Dalla Serra, M.Guella, G.Moser, C.Sinning, I.

(2024) J Mol Biol : 168821-168821

  • DOI: https://doi.org/10.1016/j.jmb.2024.168821
  • Primary Citation of Related Structures:  
    8QDQ, 8QDR

  • PubMed Abstract: 

    Lipoxygenases catalyze the peroxidation of poly-unsaturated fatty acid chains either free or esterified in membrane lipids. Vitis vinifera LoxA is transcriptionally induced at ripening onset and localizes at the inner chloroplastic membrane where it is responsible for galactolipid regiospecific mono- and di-peroxidation. Here we present a kinetic and structural characterization of LoxA. Our X-ray structures reveal a constitutive dimer with detergent induced conformational changes affecting substrate binding and catalysis. In a closed conformation, a LID domain prevents substrate access to the catalytic site by steric hindrance. Detergent addition above the CMC destabilizes the LID and opens the dimer with both catalytic sites accessible from the same surface framed by the PLAT domains. As a consequence, detergent molecules occupy allosteric sites in the PLAT/catalytic domain interfaces. These structural changes are mirrored by increased enzymatic activity and positive cooperativity when the substrate is provided in micelles. The ability to interact with micelles is lost upon dimer destabilization by site-directed mutagenesis as assessed by tryptophan fluorescence. Our data allow to propose a model for protein activation at the membrane, classifying LoxA as an interfacial enzyme acting on fatty acid chains directly from the membrane similar to mammalian 15-LOX and 5-LOX.


  • Organizational Affiliation

    Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38098 San Michele all'Adige, Italy.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Lipoxygenase
A, B
863Vitis viniferaMutation(s): 0 
Gene Names: VIT_06s0004g01510
EC: 1.13.11
UniProt
Find proteins for D7SLA9 (Vitis vinifera)
Explore D7SLA9 
Go to UniProtKB:  D7SLA9
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupD7SLA9
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.235 
  • R-Value Work: 0.199 
  • R-Value Observed: 0.201 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 85.767α = 90
b = 110.647β = 90.235
c = 91.173γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
Aimlessdata scaling
XDSdata reduction
PHENIXphasing

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
German Research Foundation (DFG)Germany--

Revision History  (Full details and data files)

  • Version 1.0: 2024-10-30
    Type: Initial release