2ADQ

Human Manganese Superoxide Dismutase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.240 
  • R-Value Work: 0.217 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Crystal structure of nitrated human manganese superoxide dismutase: mechanism of inactivation.

Quint, P.Reutzel, R.Mikulski, R.McKenna, R.Silverman, D.N.

(2006) FREE RADIC.BIOL.MED. 40: 453-458

  • DOI: 10.1016/j.freeradbiomed.2005.08.045
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • A cellular consequence of the reaction of superoxide and nitric oxide is enhanced peroxynitrite levels. Reaction of peroxynitrite with manganese superoxide dismutase (MnSOD) causes nitration of the active-site residue Tyr34 and nearly complete inhibi ...

    A cellular consequence of the reaction of superoxide and nitric oxide is enhanced peroxynitrite levels. Reaction of peroxynitrite with manganese superoxide dismutase (MnSOD) causes nitration of the active-site residue Tyr34 and nearly complete inhibition of catalysis. We report the crystal structures at 2.4 A resolution of human MnSOD nitrated by peroxynitrite and the unmodified MnSOD. A comparison of these structures showed no significant conformational changes of active-site residues or solvent displacement. The side chain of 3-nitrotyrosine 34 had a single conformation that extended toward the manganese with O1 of the nitro group within hydrogen-bonding distance (3.1 A) of Nepsilon2 of the second-shell ligand Gln143. Also, nitration of Tyr34 caused a weakening, as evidenced by the lengthening, of a hydrogen bond between its phenolic OH and Gln143, part of an extensive hydrogen-bond network in the active site. Inhibition of catalysis can be attributed to a steric effect of 3-nitrotyrosine 34 that impedes substrate access and binding, and alteration of the hydrogen-bond network that supports proton transfer in catalysis. It is also possible that an electrostatic effect of the nitro group has altered the finely tuned redox potential necessary for efficient catalysis, although the redox potential of nitrated MnSOD has not been measured.


    Organizational Affiliation

    Department of Pharmacology and Therapeutics, College of Medicine, University of Florida, Gainesville, FL 32610-0245, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Superoxide dismutase [Mn]
B
198Homo sapiensMutation(s): 0 
Gene Names: SOD2
EC: 1.15.1.1
Find proteins for P04179 (Homo sapiens)
Go to Gene View: SOD2
Go to UniProtKB:  P04179
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
K
Query on K

Download SDF File 
Download CCD File 
B
POTASSIUM ION
K
NPYPAHLBTDXSSS-UHFFFAOYSA-N
 Ligand Interaction
MN
Query on MN

Download SDF File 
Download CCD File 
B
MANGANESE (II) ION
Mn
WAEMQWOKJMHJLA-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.240 
  • R-Value Work: 0.217 
  • Space Group: P 61 2 2
Unit Cell:
Length (Å)Angle (°)
a = 81.159α = 90.00
b = 81.159β = 90.00
c = 242.165γ = 120.00
Software Package:
Software NamePurpose
CNSrefinement
DENZOdata reduction
CNSphasing
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-07-04
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2011-11-16
    Type: Atomic model