2FD9

X-ray Crystal Structure of Chemically Synthesized Crambin-{alpha}carboxamide


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6 Å
  • R-Value Free: 0.234 
  • R-Value Work: 0.216 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Role of a salt bridge in the model protein crambin explored by chemical protein synthesis: X-ray structure of a unique protein analogue, [V15A]crambin-alpha-carboxamide.

Bang, D.Tereshko, V.Kossiakoff, A.A.Kent, S.B.

(2009) Mol Biosyst 5: 750-756

  • DOI: 10.1039/b903610e
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • We have used total chemical synthesis to prepare [V15A]crambin-alpha-carboxamide, a unique protein analogue that eliminates a salt bridge between the delta-guanidinium of the Arg(10) side chain and the alpha-carboxylate of Asn(46) at the C-terminus o ...

    We have used total chemical synthesis to prepare [V15A]crambin-alpha-carboxamide, a unique protein analogue that eliminates a salt bridge between the delta-guanidinium of the Arg(10) side chain and the alpha-carboxylate of Asn(46) at the C-terminus of the polypeptide chain. This salt bridge is thought to be important for the folding and stability of the crambin protein molecule. Folding, with concomitant disulfide bond formation, of the fully reduced [V15A]crambin-alpha-carboxamide polypeptide was less efficient than folding/disulfide formation for the [V15A]crambin polypeptide under a standard set of conditions. To probe the origin of this less efficient folding/disulfide bond formation, we separately crystallized purified synthetic [V15A]crambin-alpha-carboxamide and chemically synthesized [V15A]crambin and solved their X-ray structures. The crystal structure of [V15A]crambin-alpha-carboxamide showed that elimination of the Arg(10)-Asn(46) salt bridge caused disorder of the C-terminal region of the polypeptide chain and affected the overall 'tightness' of the structure of the protein molecule. These studies, enabled by chemical protein synthesis, strongly suggest that in native crambin the Arg(10)-Asn(46) salt bridge contributes to efficient formation of correct disulfide bonds and also to the well-ordered structure of the protein molecule.


    Organizational Affiliation

    Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL 60637, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Crambin
A
46Crambe hispanica subsp. abyssinicaMutation(s): 0 
Gene Names: THI2
Find proteins for P01542 (Crambe hispanica subsp. abyssinica)
Go to UniProtKB:  P01542
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6 Å
  • R-Value Free: 0.234 
  • R-Value Work: 0.216 
  • Space Group: H 3 2
Unit Cell:
Length (Å)Angle (°)
a = 67.581α = 90.00
b = 67.581β = 90.00
c = 39.487γ = 120.00
Software Package:
Software NamePurpose
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-01-16
    Type: Initial release
  • Version 1.1: 2008-05-01
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Advisory, Version format compliance