7PTI

STRUCTURAL EFFECTS INDUCED BY REMOVAL OF A DISULFIDE BRIDGE. THE X-RAY STRUCTURE OF THE C30A(SLASH)C51A MUTANT OF BASIC PANCREATIC TRYPSIN INHIBITOR AT 1.6 ANGSTROMS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6 Å

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural effects induced by removal of a disulfide-bridge: the X-ray structure of the C30A/C51A mutant of basic pancreatic trypsin inhibitor at 1.6 A.

Eigenbrot, C.Randal, M.Kossiakoff, A.A.

(1990) Protein Eng. 3: 591-598


  • PubMed Abstract: 
  • The X-ray structure of a variant of basic pancreatic trypsin inhibitor (BPTI) has been analyzed to determine the structural accommodation resulting from removal of a disulfide cross-link in a protein. The disulfide removed, Cys30-Cys51, has been impl ...

    The X-ray structure of a variant of basic pancreatic trypsin inhibitor (BPTI) has been analyzed to determine the structural accommodation resulting from removal of a disulfide cross-link in a protein. The disulfide removed, Cys30-Cys51, has been implicated in both the folding pathway of the protein and its overall thermal stability. In the variant studied, C30A/C51A, the disulfide cysteines were replaced by less bulky alanines. The atomic displacements observed for C30A/C51A indicate a set of concerted shifts of two segments of chains, which together significantly diminish a packing defect at the site of the removed cysteine sulfur atoms. The observed structural changes are distributed asymmetrically around the sites of mutation, indicating that the adjacent beta-sheet is more resistant to the perturbation than the alpha-helix on the opposite side of the disulfide bond. The thermal parameters of groups involved in the structural accommodation are not significantly altered. A comparison of the X-ray structures reported for native BPTI determined in three different crystal forms indicates that the magnitude of its conformational variability exceeds that of the structural changes caused by the disulfide removal. This emphasizes the necessity of using isomorphous crystal systems to determine the relatively small effects due to mutation.


    Organizational Affiliation

    Department of Biomolecular Chemistry, Genentech Inc., South San Francisco, CA 94080.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
BOVINE PANCREATIC TRYPSIN INHIBITOR
A
58Bos taurusMutation(s): 0 
Find proteins for P00974 (Bos taurus)
Go to UniProtKB:  P00974
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PO4
Query on PO4

Download SDF File 
Download CCD File 
A
PHOSPHATE ION
O4 P
NBIIXXVUZAFLBC-UHFFFAOYSA-K
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6 Å
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 74.360α = 90.00
b = 23.260β = 90.00
c = 28.880γ = 90.00
Software Package:
Software NamePurpose
PROLSQrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1991-04-15
    Type: Initial release
  • Version 1.1: 2008-03-25
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance