1T8N

CRYSTAL STRUCTURE OF THE P1 THR BPTI MUTANT- BOVINE CHYMOTRYPSIN COMPLEX


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.75 Å
  • R-Value Free: 0.214 
  • R-Value Work: 0.200 
  • R-Value Observed: 0.200 

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

Crystal structures of five bovine chymotrypsin complexes with P1 BPTI variants.

Czapinska, H.Helland, R.Smalas, A.O.Otlewski, J.

(2004) J Mol Biol 344: 1005-1020

  • DOI: https://doi.org/10.1016/j.jmb.2004.09.088
  • Primary Citation of Related Structures:  
    1T7C, 1T8L, 1T8M, 1T8N, 1T8O

  • PubMed Abstract: 

    The bovine chymotrypsin-bovine pancreatic trypsin inhibitor (BPTI) interaction belongs to extensively studied models of protein-protein recognition. The accommodation of the inhibitor P1 residue in the S1 binding site of the enzyme forms the hot spot of this interaction. Mutations introduced at the P1 position of BPTI result in a more than five orders of magnitude difference of the association constant values with the protease. To elucidate the structural aspects of the discrimination between different P1 residues, crystal structures of five bovine chymotrypsin-P1 BPTI variant complexes have been determined at pH 7.8 to a resolution below 2 A. The set includes polar (Thr), ionizable (Glu, His), medium-sized aliphatic (Met) and large aromatic (Trp) P1 residues and complements our earlier studies of the interaction of different P1 side-chains with the S1 pocket of chymotrypsin. The structures have been compared to the complexes of proteases with similar and dissimilar P1 preferences, including Streptomyces griseus proteases B and E, human neutrophil elastase, crab collagenase, bovine trypsin and human thrombin. The S1 sites of these enzymes share a common general shape of significant rigidity. Large and branched P1 residues adapt in their complexes similar conformations regardless of the polarity and size differences between their S1 pockets. Conversely, long and flexible residues such as P1 Met are present in the disordered form and display a conformational diversity despite similar inhibitory properties with respect to most enzymes studied. Thus, the S1 specificity profiles of the serine proteases appear to result from the precise complementarity of the P1-S1 interface and minor conformational adjustments occurring upon the inhibitor binding.


  • Organizational Affiliation

    Laboratory of Protein Engineering, Institute of Biochemistry and Molecular Biology, University of Wroclaw, Tamka 2, 50-137 Wroclaw, Poland.


Macromolecules
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Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Chymotrypsin A
A, C
245Bos taurusMutation(s): 0 
EC: 3.4.21.1
UniProt
Find proteins for P00766 (Bos taurus)
Explore P00766 
Go to UniProtKB:  P00766
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP00766
Sequence Annotations
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Pancreatic trypsin inhibitor
B, D
58Bos taurusMutation(s): 2 
UniProt
Find proteins for P00974 (Bos taurus)
Explore P00974 
Go to UniProtKB:  P00974
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP00974
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.75 Å
  • R-Value Free: 0.214 
  • R-Value Work: 0.200 
  • R-Value Observed: 0.200 
  • Space Group: P 61
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 99.96α = 90
b = 99.96β = 90
c = 205.36γ = 120
Software Package:
Software NamePurpose
CNSrefinement
DENZOdata reduction
CCP4data scaling
CNSphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2005-03-08
    Type: Initial release
  • Version 1.1: 2008-04-30
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2021-10-27
    Changes: Database references, Derived calculations
  • Version 1.4: 2023-08-23
    Changes: Data collection, Refinement description