2FXY

Solution structure of 55-72 segment of staphylococcal nuclease


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 80 
  • Conformers Submitted: 15 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Two peptide fragments G55-I72 and K97-A109 from staphylococcal nuclease exhibit different behaviors in conformational preferences for helix formation

Wang, M.Shan, L.Wang, J.F.

(2006) Biopolymers 83: 268-279

  • DOI: 10.1002/bip.20558
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Two synthetic peptides, SNasealpha1 and SNasealpha2, corresponding to residues G55-I72 and K97-A109, respectively, of staphylococcal nuclease (SNase), are adopted for detecting the role of helix alpha1 (E57-A69) and helix alpha2 (M98-Q106) in the ini ...

    Two synthetic peptides, SNasealpha1 and SNasealpha2, corresponding to residues G55-I72 and K97-A109, respectively, of staphylococcal nuclease (SNase), are adopted for detecting the role of helix alpha1 (E57-A69) and helix alpha2 (M98-Q106) in the initiation of folding of SNase. The helix-forming tendencies of the two SNase peptide fragments are investigated using circular dichroism (CD) and two-dimensional (2D) nuclear magnetic resonance (NMR) methods in water and 40% trifluoroethanol (TFE) solutions. The coil-helix conformational transitions of the two peptides in the TFE-H2O mixture are different from each other. SNasealpha1 adopts a low population of localized helical conformation in water, and shows a gradual transition to helical conformation with increasing concentrations of TFE. SNasealpha2 is essentially unstructured in water, but undergoes a cooperative transition to a predominantly helical conformation at high TFE concentrations. Using the NMR data obtained in the presence of 40% TFE, an ensemble of alpha-helical structures has been calculated for both peptides in the absence of tertiary interactions. Analysis of all the experimental data available indicates that formation of ordered alpha-helical structures in the segments E57-A69 and M98-Q106 of SNase may require nonlocal interactions through transient contact with hydrophobic residues in other parts of the protein to stabilize the helical conformations in the folding. The folding of helix alpha1 is supposed to be effective in initiating protein folding. The formation of helix alpha2 depends strongly on the hydrophobic environment created in the protein folding, and is more important in the stabilization of the tertiary conformation of SNase.


    Organizational Affiliation

    National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Beijing 100101, People's Republic of China.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
18-mer peptide from Thermonuclease
A
18Staphylococcus aureusMutation(s): 0 
Gene Names: nuc
Find proteins for Q1WCB7 (Staphylococcus aureus)
Go to UniProtKB:  Q1WCB7
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 80 
  • Conformers Submitted: 15 
  • Selection Criteria: structures with the lowest energy 
  • Olderado: 2FXY Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-12-19
    Type: Initial release
  • Version 1.1: 2008-05-01
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance