1PM9

CRYSTAL STRUCTURE OF HUMAN MNSOD H30N, Y166F MUTANT


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Free: 0.239 
  • R-Value Work: 0.215 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Amino acid substitution at the dimeric interface of human manganese superoxide dismutase

Hearn, A.S.Fan, L.Lepock, J.R.Luba, J.P.Greenleaf, W.B.Cabelli, D.E.Tainer, J.A.Nick, H.S.Silverman, D.N.

(2004) J.Biol.Chem. 279: 5861-5866

  • DOI: 10.1074/jbc.M311310200
  • Primary Citation of Related Structures:  1PL4

  • PubMed Abstract: 
  • The side chains of His30 and Tyr166 from adjacent subunits in the homotetramer human manganese superoxide dismutase (Mn-SOD) form a hydrogen bond across the dimer interface and participate in a hydrogen-bonded network that extends to the active site. ...

    The side chains of His30 and Tyr166 from adjacent subunits in the homotetramer human manganese superoxide dismutase (Mn-SOD) form a hydrogen bond across the dimer interface and participate in a hydrogen-bonded network that extends to the active site. Compared with wild-type Mn-SOD, the site-specific mutants H30N, Y166F, and the corresponding double mutant showed 10-fold decreases in steady-state constants for catalysis measured by pulse radiolysis. The observation of no additional effect upon the second mutation is an example of cooperatively interacting residues. A similar effect was observed in the thermal stability of these enzymes; the double mutant did not reduce the major unfolding transition to an extent greater than either single mutant. The crystal structures of these site-specific mutants each have unique conformational changes, but each has lost the hydrogen bond across the dimer interface, which results in a decrease in catalysis. These same mutations caused an enhancement of the dissociation of the product-inhibited complex. That is, His30 and Tyr166 in wild-type Mn-SOD act to prolong the lifetime of the inhibited complex. This would have a selective advantage in blocking a cellular overproduction of toxic H2O2.


    Organizational Affiliation

    Departments of Pharmacology and Neuroscience, University of Florida, Gainesville, Florida 32610-0267, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Superoxide dismutase [Mn], mitochondrial
A, B
198Homo sapiensGene 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 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MN3
Query on MN3

Download SDF File 
Download CCD File 
A, B
MANGANESE (III) ION
Mn
MMIPFLVOWGHZQD-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Free: 0.239 
  • R-Value Work: 0.215 
  • Space Group: P 21 21 2
Unit Cell:
Length (Å)Angle (°)
a = 71.580α = 90.00
b = 76.460β = 90.00
c = 66.610γ = 90.00
Software Package:
Software NamePurpose
DENZOdata reduction
MOLREPphasing
SCALEPACKdata scaling
CNSrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2003-06-10 
  • Released Date: 2003-12-16 
  • Deposition Author(s): Fan, L., Tainer, J.A.

Revision History 

  • Version 1.0: 2003-12-16
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Derived calculations, Version format compliance