4ZN0

Structure of the NADPH-dependent thioredoxin reductase from Methanosarcina mazei


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.60 Å
  • R-Value Free: 0.241 
  • R-Value Work: 0.217 
  • R-Value Observed: 0.218 

Starting Model: experimental
View more details

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Crystal Structure of the Apo-Form of NADPH-Dependent Thioredoxin Reductase from a Methane-Producing Archaeon.

Buey, R.M.Schmitz, R.A.Buchanan, B.B.Balsera, M.

(2018) Antioxidants (Basel) 7

  • DOI: https://doi.org/10.3390/antiox7110166
  • Primary Citation of Related Structures:  
    4ZN0

  • PubMed Abstract: 

    The redox regulation of proteins via reversible dithiol/disulfide exchange reactions involves the thioredoxin system, which is composed of a reductant, a thioredoxin reductase (TR), and thioredoxin (Trx). In the pyridine nucleotide-dependent Trx reduction pathway, reducing equivalents, typically from reduced nicotinamide adenine dinucleotide phosphate (NADPH), are transferred from NADPH-TR (NTR) to Trx and, in turn, to target proteins, thus resulting in the reversible modification of the structural and functional properties of the targets. NTR enzymes contain three functional sites: an NADPH binding pocket, a non-covalently bound flavin cofactor, and a redox-active disulfide in the form of CxxC. With the aim of increasing our knowledge of the thioredoxin system in archaea, we here report the high-resolution crystal structure of NTR from the methane-generating organism Methanosarcina mazei strain Gö1 (MmNTR) at 2.6 Å resolution. Based on the crystals presently described, MmNTR assumes an overall fold that is nearly identical to the archetypal fold of authentic NTRs; however, surprisingly, we observed no electron density for flavin adenine dinucleotide (FAD) despite the well-defined and conserved FAD-binding cavity in the folded module. Remarkably, the dimers of the apo-protein within the crystal were different from those observed by small angle X-ray scattering (SAXS) for the holo-protein, suggesting that the binding of the flavin cofactor does not require major protein structural rearrangements. Rather, binding results in the stabilization of essential parts of the structure, such as those involved in dimer stabilization. Altogether, this structure represents the example of an apo-form of an NTR that yields important insight into the effects of the cofactor on protein folding.


  • Organizational Affiliation

    Metabolic Engineering Group. Dpto. Microbiología y Genética. Universidad de Salamanca, 37007 Salamanca, Spain. ruben.martinez@usal.es.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Thioredoxin reductase
A, B, C, D
311Methanosarcina mazei Go1Mutation(s): 0 
Gene Names: MM_2353
EC: 1.8.1.9
UniProt
Find proteins for Q8PUI1 (Methanosarcina mazei (strain ATCC BAA-159 / DSM 3647 / Goe1 / Go1 / JCM 11833 / OCM 88))
Explore Q8PUI1 
Go to UniProtKB:  Q8PUI1
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ8PUI1
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.60 Å
  • R-Value Free: 0.241 
  • R-Value Work: 0.217 
  • R-Value Observed: 0.218 
  • Space Group: C 2 2 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 117.144α = 90
b = 182.5β = 90
c = 152.046γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
XDSdata reduction
XSCALEdata scaling
PHASERphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2016-06-29
    Type: Initial release
  • Version 1.1: 2019-04-24
    Changes: Data collection, Database references
  • Version 1.2: 2024-01-10
    Changes: Data collection, Database references, Refinement description