2LQX

NMR spatial structure of the trypsin inhibitor BWI-2c from the buckwheat seeds


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: target function 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Buckwheat trypsin inhibitor with helical hairpin structure belongs to a new family of plant defence peptides.

Oparin, P.B.Mineev, K.S.Dunaevsky, Y.E.Arseniev, A.S.Belozersky, M.A.Grishin, E.V.Egorov, T.A.Vassilevski, A.A.

(2012) Biochem.J. 446: 69-77

  • DOI: 10.1042/BJ20120548

  • PubMed Abstract: 
  • A new peptide trypsin inhibitor named BWI-2c was obtained from buckwheat (Fagopyrum esculentum) seeds by sequential affinity, ion exchange and reversed-phase chromatography. The peptide was sequenced and found to contain 41 amino acid residues, with ...

    A new peptide trypsin inhibitor named BWI-2c was obtained from buckwheat (Fagopyrum esculentum) seeds by sequential affinity, ion exchange and reversed-phase chromatography. The peptide was sequenced and found to contain 41 amino acid residues, with four cysteine residues involved in two intramolecular disulfide bonds. Recombinant BWI-2c identical to the natural peptide was produced in Escherichia coli in a form of a cleavable fusion with thioredoxin. The 3D (three-dimensional) structure of the peptide in solution was determined by NMR spectroscopy, revealing two antiparallel α-helices stapled by disulfide bonds. Together with VhTI, a trypsin inhibitor from veronica (Veronica hederifolia), BWI-2c represents a new family of protease inhibitors with an unusual α-helical hairpin fold. The linker sequence between the helices represents the so-called trypsin inhibitory loop responsible for direct binding to the active site of the enzyme that cleaves BWI-2c at the functionally important residue Arg(19). The inhibition constant was determined for BWI-2c against trypsin (1.7×10(-1)0 M), and the peptide was tested on other enzymes, including those from various insect digestive systems, revealing high selectivity to trypsin-like proteases. Structural similarity shared by BWI-2c, VhTI and several other plant defence peptides leads to the acknowledgement of a new widespread family of plant peptides termed α-hairpinins.


    Organizational Affiliation

    M. M. Shemyakin and Yu. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Trypsin inhibitor BWI-2c
A
41N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: target function 
  • Olderado: 2LQX Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-05-30
    Type: Initial release
  • Version 1.1: 2012-08-08
    Type: Database references