1JV8

NMR Structure of BPTI Mutant G37A


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 50 
  • Conformers Submitted: 23 
  • Selection Criteria: structures with the least restraint violations 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

A highly destabilizing mutation, G37A, of the bovine pancreatic trypsin inhibitor retains the average native conformation but greatly increases local flexibility

Battiste, J.L.Li, R.Woodward, C.

(2002) Biochemistry 41: 2237-2245

  • Primary Citation of Related Structures:  1JV9

  • PubMed Abstract: 
  • A point mutation, G37A, on the surface of bovine pancreatic trypsin inhibitor (BPTI) destabilizes the protein by approximately 5 kcal/mol, which is very high for addition of one methyl group. In wild-type (WT) BPTI, Gly 37 HN is in an unusual NH-arom ...

    A point mutation, G37A, on the surface of bovine pancreatic trypsin inhibitor (BPTI) destabilizes the protein by approximately 5 kcal/mol, which is very high for addition of one methyl group. In wild-type (WT) BPTI, Gly 37 HN is in an unusual NH-aromatic-NH network of interactions with the ring of Tyr 35 and the side chain HN of Asn 44. G37A was designed to disrupt this interaction, since the phi and psi backbone angles of G37 are not favorable for an amino acid containing a beta-carbon. Investigations of the structure and dynamics by NMR methods show that G37A retains the average WT structure. The NH-aromatic-NH interactions remain intact, as indicated by NOEs and the large upfield ring current shift (approximately 4 ppm) of A37 HN. The NMR structure, confirmed by molecular modeling calculations, requires phi and psi backbone angles that are highly destabilizing when alanine is in position 37. Although the average structure is essentially unchanged, the dynamics are altered dramatically. Many residues in the region of the mutation have increased flexibility, as probed by aromatic ring flip rates and native state hydrogen exchange. We conclude that a large fraction of the destabilization arises from maintaining A37 in a high-energy conformation. This suggests that disruption of the NH-aromatic-NH network is energetically very costly, and may involve other cooperatively linked interactions. The results illustrate the importance of the Gly-Gly sequence at positions 36 and 37 and the 37 HN-35 aromatic interaction to the stability, folding, and dynamics of the BPTI.


    Related Citations: 
    • Native-like Interactions Favored in the Unfolded Bovine Pancreatic Trypsin Inhibitor Have Different Roles in Folding.
      Li, R.,Battiste, J.L.,Woodward, C.
      (2002) Biochemistry 41: 2246


    Organizational Affiliation

    Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, 1479 Gortner Avenue, St. Paul, Minnesota 55108, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
TRYPSIN INHIBITOR
A
58Bos taurusN/A
Find proteins for P00974 (Bos taurus)
Go to UniProtKB:  P00974
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 50 
  • Conformers Submitted: 23 
  • Selection Criteria: structures with the least restraint violations 
  • Olderado: 1JV8 Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2001-09-12
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance