1BSC

CRYSTAL STRUCTURAL ANALYSIS OF MUTATIONS IN THE HYDROPHOBIC CORES OF BARNASE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Crystal structural analysis of mutations in the hydrophobic cores of barnase.

Buckle, A.M.Henrick, K.Fersht, A.R.

(1993) J.Mol.Biol. 234: 847-860

  • DOI: 10.1006/jmbi.1993.1630
  • Primary Citation of Related Structures:  1BNI, 1BNJ, 1BSA, 1BSB, 1BSD, 1BSE

  • PubMed Abstract: 
  • We have solved and analysed the crystal structures of five mutants in the hydrophobic core of barnase to investigate the structural basis for the contribution of hydrophobic residues and side-chain packing to the stability of globular proteins. In ca ...

    We have solved and analysed the crystal structures of five mutants in the hydrophobic core of barnase to investigate the structural basis for the contribution of hydrophobic residues and side-chain packing to the stability of globular proteins. In case ease, an amino acid side-chain has been replaced with one of smaller volume. The overall structures of four Ile-->Val mutants (residues 51, 76, 88 and 96) and one Leu-->Val mutant (residue 89) are all isomorphous with the wild-type structure. The magnitude and nature of structural shifts in the three hydrophobic core regions of barnase depend on the local environment of the substitution site, but have some features in common. (1) Side-chain atoms move to a greater extent than do main-chain atoms. (2) Repacking at the substitution site is achieved by either a rigid body shift of side-chain atoms (for Ile-->Val76 and Ile-->Val96 mutants), or by a combination of a side-chain shift and rotation (for Ile-->Val51 and Ile-->Val88 mutants). The mutated residue moves to the greatest extent, and generally in the direction of the created cavity (the largest atomic shift is 0.9 A, for Ile-->Val51). The space left behind from such shifts is not seen to be filled by neighbouring side-chains. (3) Where a cavity remains after mutation, it does not contain any solvent molecules. (4) There is no correlation between the extent of structural movements and the atomic temperature factors of atoms that have moved. (5) Structural movements are not large enough to disrupt hydrogen bonding. Valine 88, in the Ile-->Val88 mutant, is disordered and the electron density suggests several side-chain conformations. The reduction in the volumes of the cavities introduced upon mutation, due to collapse of the surrounding structure, ranges from 11% (Ile-->Val96) to 90% (Ile-->Val51).


    Related Citations: 
    • Molecular Structures of a New Family of Ribonucleases
      Mauguen, Y.,Hartley, R.W.,Dodson, E.J.,Dodson, G.G.,Bricogne, G.,Chothia, C.,Jack, A.
      (1982) Nature 297: 162
    • The Folding of an Enzyme. II. Substructure of Barnase and the Contribution of Different Interactions to Protein Stability
      Serrano, L.,Kellis Junior, J.T.,Cann, P.,Matouschek, A.,Fersht, A.R.
      (1992) J.Mol.Biol. 224: 783


    Organizational Affiliation

    Centre for Protein Engineering, Medical Research Council Centre, Cambridge, U.K.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
BARNASE
A, B, C
110Bacillus amyloliquefaciensEC: 3.1.27.-
Find proteins for P00648 (Bacillus amyloliquefaciens)
Go to UniProtKB:  P00648
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • Space Group: P 32
Unit Cell:
Length (Å)Angle (°)
a = 58.710α = 90.00
b = 58.710β = 90.00
c = 81.550γ = 120.00
Software Package:
Software NamePurpose
PROLSQrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1994-01-31
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2017-11-29
    Type: Derived calculations, Other