5XW9

Crystal Structure of Porcine pancreatic trypsin with tripeptide inhibitor, PRY, at pH 7


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.194 
  • R-Value Work: 0.165 
  • R-Value Observed: 0.166 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Tripeptides derived from reactive centre loop of potato type II protease inhibitors preferentially inhibit midgut proteases of Helicoverpa armigera.

Saikhedkar, N.S.Joshi, R.S.Bhoite, A.S.Mohandasan, R.Yadav, A.K.Fernandes, M.Kulkarni, K.A.Giri, A.P.

(2018) Insect Biochem Mol Biol 95: 17-25

  • DOI: https://doi.org/10.1016/j.ibmb.2018.02.001
  • Primary Citation of Related Structures:  
    5XW8, 5XW9, 5XWA, 5XWJ, 5XWL

  • PubMed Abstract: 

    Potato type II protease inhibitors (Pin-II PIs) impede the growth of lepidopteran insects by inhibiting serine protease-like enzymes in the larval gut. The three amino acid reactive centre loop (RCL) of these proteinaceous inhibitors is crucial for protease binding and is conserved across the Pin-II family. However, the molecular mechanism and inhibitory potential of the RCL tripeptides in isolation of the native protein has remained elusive. In this study, six peptides corresponding to the RCLs of the predominant Pin-II PIs were identified, synthesized and evaluated for in vitro and in vivo inhibitory activity against serine proteases of the polyphagous insect, Helicoverpa armigera. RCL peptides with sequences PRN, PRY and TRE were found to be potent inhibitors that adversely affected the growth and development of H. armigera. The binding mechanism and differential affinity of the RCL peptides with serine proteases was delineated by crystal structures of complexes of the RCL peptides with trypsin. Residues P1 and P2 of the inhibitors play a crucial role in the interaction and specificity of these inhibitors. Important features of RCL peptides like higher inhibition of insect proteases, enhanced efficacy at alkaline gut pH, longer retention and high stability in insect gut make them suitable molecules for the development of sustainable pest management strategies for crop protection.


  • Organizational Affiliation

    Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411 008, India.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Trypsin133Sus scrofaMutation(s): 0 
EC: 3.4.21.4
UniProt
Find proteins for P00761 (Sus scrofa)
Explore P00761 
Go to UniProtKB:  P00761
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP00761
Sequence Annotations
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Trypsin98Sus scrofaMutation(s): 0 
EC: 3.4.21.4
UniProt
Find proteins for P00761 (Sus scrofa)
Explore P00761 
Go to UniProtKB:  P00761
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP00761
Sequence Annotations
Expand
  • Reference Sequence

Find similar proteins by:  Sequence   |   3D Structure  

Entity ID: 3
MoleculeChains Sequence LengthOrganismDetailsImage
Acetylated-Pro-Arg-Tyr Inhibitor4Capsicum annuumMutation(s): 0 
Sequence Annotations
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
CA
Query on CA

Download Ideal Coordinates CCD File 
D [auth A]CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.194 
  • R-Value Work: 0.165 
  • R-Value Observed: 0.166 
  • Space Group: P 61 2 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 82.665α = 90
b = 82.665β = 90
c = 134.674γ = 120
Software Package:
Software NamePurpose
PHENIXrefinement
XDSdata reduction
SCALAdata scaling
PHASERphasing

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
CSIRIndiaBSC0120

Revision History  (Full details and data files)

  • Version 1.0: 2018-03-28
    Type: Initial release
  • Version 1.1: 2018-04-11
    Changes: Data collection, Database references
  • Version 1.2: 2023-11-22
    Changes: Advisory, Data collection, Database references, Derived calculations, Refinement description