1EY5

STRUCTURE OF S. NUCLEASE STABILIZING MUTANT T33V


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Free: 0.266 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Increasing the thermostability of staphylococcal nuclease: implications for the origin of protein thermostability.

Chen, J.Lu, Z.Sakon, J.Stites, W.E.

(2000) J.Mol.Biol. 303: 125-130

  • DOI: 10.1006/jmbi.2000.4140
  • Primary Citation of Related Structures:  1EY0, 1EY4, 1EY6, 1EY7, 1EY8, 1EY9, 1EYA, 1EYC, 1EYD, 1EZ6, 1EZ8

  • PubMed Abstract: 
  • Seven hyper-stable multiple mutants have been constructed in staphylococcal nuclease by various combinations of eight different stabilizing single mutants. The stabilities of these multiple mutants determined by guanidine hydrochloride denaturation w ...

    Seven hyper-stable multiple mutants have been constructed in staphylococcal nuclease by various combinations of eight different stabilizing single mutants. The stabilities of these multiple mutants determined by guanidine hydrochloride denaturation were 3.4 to 5.6 kcal/mol higher than that of the wild-type. Their thermal denaturation midpoint temperatures were 12.6 to 22.9 deg. C higher than that of the wild-type. These are among the greatest increases in protein stability and thermal denaturation midpoint temperature relative to the wild-type yet attained. There has been great interest in understanding how proteins found in thermophilic organisms are stabilized. One frequently cited theory is that the packing of hydrophobic side-chains is improved in the cores of proteins isolated from thermophiles when compared to proteins from mesophiles. The crystal structures of four single and five multiple stabilizing mutants of staphylococcal nuclease were solved to high resolution. No large overall structural change was found, with most changes localized around the sites of mutation. Rearrangements were observed in the packing of side-chains in the major hydrophobic core, although none of the mutations was in the core. It is surprising that detailed structural analysis showed that packing had improved, with the volume of the mutant protein's hydrophobic cores decreasing as protein stability increased. Further, the number of van der Waals interactions in the entire protein showed an experimentally significant increase correlated with increasing stability. These results indicate that optimization of packing follows as a natural consequence of increased protein thermostability and that good packing is not necessarily the proximate cause of high stability. Another popular theory is that thermostable proteins have more electrostatic and hydrogen bonding interactions and these are responsible for the high stabilities. The mutants here show that increased numbers of electrostatic and hydrogen bonding interactions are not obligatory for large increases in protein stability.


    Related Citations: 
    • Contributions of the Polar, Uncharged Amino Acids to the Stability of Staphylococcal Nuclease: Evidence for Mutational Effects on the Free Energy of the Denatured State.
      Green, S.M.,Meeker, A.K.,Shortle, D.
      (1992) Biochemistry 31: 5717


    Organizational Affiliation

    Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701-1201, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
STAPHYLOCOCCAL NUCLEASE
A
149Staphylococcus aureusGene Names: nuc
EC: 3.1.31.1
Find proteins for P00644 (Staphylococcus aureus)
Go to UniProtKB:  P00644
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Free: 0.266 
  • Space Group: P 41
Unit Cell:
Length (Å)Angle (°)
a = 48.083α = 90.00
b = 48.083β = 90.00
c = 63.673γ = 90.00
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
SHELXmodel building
SHELXphasing
SHELXL-97refinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2000-10-18
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance