3CYI

Crystal Structure of Human Sulfiredoxin (Srx) in Complex with ATP:Mg2+


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.80 Å
  • R-Value Free: 0.231 
  • R-Value Work: 0.201 
  • R-Value Observed: 0.202 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Reduction of Cysteine Sulfinic Acid in Peroxiredoxin by Sulfiredoxin Proceeds Directly through a Sulfinic Phosphoryl Ester Intermediate.

Jonsson, T.J.Murray, M.S.Johnson, L.C.Lowther, W.T.

(2008) J Biol Chem 283: 23846-23851

  • DOI: 10.1074/jbc.M803244200
  • Primary Citation of Related Structures:  
    3CYI

  • PubMed Abstract: 
  • Sulfiredoxin (Srx) catalyzes a novel enzymatic reaction, the reduction of protein cysteine sulfinic acid, Cys-SO(2)(-). This reaction is unique to the typical 2-Cys peroxiredoxins (Prx) and plays a role in peroxide-mediated signaling by regulating the activity of Prxs ...

    Sulfiredoxin (Srx) catalyzes a novel enzymatic reaction, the reduction of protein cysteine sulfinic acid, Cys-SO(2)(-). This reaction is unique to the typical 2-Cys peroxiredoxins (Prx) and plays a role in peroxide-mediated signaling by regulating the activity of Prxs. Two mechanistic schemes have been proposed that differ regarding the first step of the reaction. This step involves either the direct transfer of the gamma-phosphate of ATP to the Prx molecule or through Srx acting as a phosphorylated intermediary. In an effort to clarify this step of the Srx reaction, we have determined the 1.8A resolution crystal structure of Srx in complex with ATP and Mg(2+). This structure reveals the role of the Mg(2+) ion to position the gamma-phosphate toward solvent, thus preventing an in-line attack by the catalytic residue Cys-99 of Srx. A model of the quaternary complex is consistent with this proposal. Furthermore, phosphorylation studies on several site-directed mutants of Srx and Prx, including the Prx-Asp mimic of the Prx-SO(2)(-) species, support a mechanism where phosphorylation of Prx-SO(2)(-) is the first chemical step.


    Organizational Affiliation

    Center for Structural Biology and Department of Biochemistry, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Sulfiredoxin-1A110Homo sapiensMutation(s): 1 
Gene Names: SRXN1C20orf139SRXSRX1
EC: 1.8.98.2
Find proteins for Q9BYN0 (Homo sapiens)
Explore Q9BYN0 
Go to UniProtKB:  Q9BYN0
NIH Common Fund Data Resources
PHAROS:  Q9BYN0
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ATP
Query on ATP

Download Ideal Coordinates CCD File 
C [auth A]ADENOSINE-5'-TRIPHOSPHATE
C10 H16 N5 O13 P3
ZKHQWZAMYRWXGA-KQYNXXCUSA-N
 Ligand Interaction
MG
Query on MG

Download Ideal Coordinates CCD File 
B [auth A]MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.80 Å
  • R-Value Free: 0.231 
  • R-Value Work: 0.201 
  • R-Value Observed: 0.202 
  • Space Group: P 32 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 68.53α = 90
b = 68.53β = 90
c = 51.09γ = 120
Software Package:
Software NamePurpose
REFMACrefinement
ADSCdata collection
HKL-2000data reduction
HKL-2000data scaling
PHASESphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2008-07-01
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2018-01-24
    Changes: Structure summary