3TCO

Crystallographic and spectroscopic characterization of Sulfolobus solfataricus TrxA1 provide insights into the determinants of thioredoxin fold stability


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.222 
  • R-Value Work: 0.189 
  • R-Value Observed: 0.189 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Crystallographic and spectroscopic characterizations of Sulfolobus solfataricus TrxA1 provide insights into the determinants of thioredoxin fold stability.

Esposito, L.Ruggiero, A.Masullo, M.Ruocco, M.R.Lamberti, A.Arcari, P.Zagari, A.Vitagliano, L.

(2012) J Struct Biol 177: 506-512

  • DOI: 10.1016/j.jsb.2011.10.014
  • Primary Citation of Related Structures:  
    3TCO

  • PubMed Abstract: 
  • Structural characterizations of thioredoxins (Trxs) are important for their involvement in severe pathologies and for their stable scaffold. Here we report a combined structural and spectroscopic characterization of a Trx isolated from the hypertherm ...

    Structural characterizations of thioredoxins (Trxs) are important for their involvement in severe pathologies and for their stable scaffold. Here we report a combined structural and spectroscopic characterization of a Trx isolated from the hyperthermophilic archaeon Sulfolobus solfataricus (SsTrxA1). Thermal denaturation unveils that SsTrxA1 is endowed with a remarkable stability in the explored temperature range 50-105°C. The structure of the oxidized form of SsTrxA1 determined at 1.9Å resolution presents a number of peculiar features. Although the protein was crystallized in a slightly acid medium (pH 6.5) as many as ten intramolecular/intermolecular carboxyl-carboxylate interactions involving glutamic and aspartic acid side chains are found in three independent SsTrxA1 molecules present in the asymmetric unit. Surprisingly for a hyperthermostable protein, the structure of SsTrxA1 is characterized by the presence (a) of a very limited number of intramolecular salt bridges and (b) of a cavity nearby Cys52, a residue that is frequently a phenylananine in other members of the family. Chemical denaturation investigations carried out on SsTrxA1 and SsTrxA2 show that both proteins present a significant stability against guanidine hydrochloride, thus indicating that ionic interactions play a minor role in their stabilization. Compared to Trxs from mesophilic sources, SsTrxA1 displays a longer α-helix 1 and a shorter loop connecting this α-helix with β-strand 2. As these features are shared with Trxs isolated from thermophilic sources, the shortening of this loop may be a general strategy adopted to stabilize this fold. This feature may be exploited for the design of hyperthermostable Trx scaffolds.


    Organizational Affiliation

    Istituto di Biostrutture e Bioimmagini, CNR, Via Mezzocannone 16, I-80134 Napoli, Italy.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Thioredoxin (TrxA-1)A, B, C109Saccharolobus solfataricusMutation(s): 0 
Gene Names: trxA-1SSO0368
Find proteins for Q980E5 (Saccharolobus solfataricus (strain ATCC 35092 / DSM 1617 / JCM 11322 / P2))
Explore Q980E5 
Go to UniProtKB:  Q980E5
Protein Feature View
 ( Mouse scroll to zoom / Hold left click to move )
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
EDO
Query on EDO

Download CCD File 
A, B, C
1,2-ETHANEDIOL
C2 H6 O2
LYCAIKOWRPUZTN-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.222 
  • R-Value Work: 0.189 
  • R-Value Observed: 0.189 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 51.76α = 90
b = 75.09β = 112.64
c = 55.35γ = 90
Software Package:
Software NamePurpose
CrystalCleardata collection
PHASESphasing
CNSrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-11-30
    Type: Initial release
  • Version 1.1: 2012-03-07
    Changes: Database references