1JQG

Crystal Structure of the Carboxypeptidase A from Helicoverpa Armigera


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.5 Å
  • R-Value Free: 0.238 
  • R-Value Work: 0.180 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal structure of a novel mid-gut procarboxypeptidase from the cotton pest Helicoverpa armigera.

Estebanez-Perpina, E.Bayes, A.Vendrell, J.Jongsma, M.A.Bown, D.P.Gatehouse, J.A.Huber, R.Bode, W.Aviles, F.X.Reverter, D.

(2001) J.Mol.Biol. 313: 629-638

  • DOI: 10.1006/jmbi.2001.5076

  • PubMed Abstract: 
  • The cotton bollworm Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) is one of the most serious insect pests in Australia, India and China. The larva causes substantial economical losses to legume, fibre, cereal oilseed and vegetable crops. Thi ...

    The cotton bollworm Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) is one of the most serious insect pests in Australia, India and China. The larva causes substantial economical losses to legume, fibre, cereal oilseed and vegetable crops. This pest has proven to be difficult to control by conventional means, mainly due to the development of pesticide resistance. We present here the 2.5 A crystal structure from the novel procarboxypeptidase (PCPAHa) found in the gut extracts from H. armigera larvae, the first one reported for an insect. This metalloprotease is synthesized as a zymogen of 46.6 kDa which, upon in vitro activation with Lys-C endoproteinase, yields a pro-segment of 91 residues and an active carboxypeptidase moiety of 318 residues. Both regions show a three-dimensional structure quite similar to the corresponding structures in mammalian digestive carboxypeptidases, the most relevant structural differences being located in the loops between conserved secondary structure elements, including the primary activation site. This activation site contains the motif (Ala)(5)Lys at the C terminus of the helix connecting the pro- and the carboxypeptidase domains. A remarkable feature of PCPAHa is the occurrence of the same (Ala)(6)Lys near the C terminus of the active enzyme. The presence of Ser255 in PCPAHa instead of Ile and Asp found in the pancreatic A and B forms, respectively, enlarges the S1' specificity pocket and influences the substrate preferences of the enzyme. The C-terminal tail of the leech carboxypeptidase inhibitor has been modelled into the PCPAHa active site to explore the substrate preferences and the enzymatic mechanism of this enzyme.


    Related Citations: 
    • Midgut carboxypeptidase from Helicoverpa armigera (Lepidoptera: Noctuidae) larvae: enzyme characterisation, cDNA cloning and expression.
      Bown, D.P.,Wilkinson, H.S.,Gatehouse, J.A.
      (1998) Insect Biochem.Mol.Biol. 28: 739


    Organizational Affiliation

    Abteilung für Strukturforschung, Max-Planck-Institut für Biochemie, Am Klopferspitz 18a, D-82152 Planegg-Martinsried, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
carboxypeptidase A
A
433Helicoverpa armigeraEC: 3.4.17.1
Find proteins for O97389 (Helicoverpa armigera)
Go to UniProtKB:  O97389
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download SDF File 
Download CCD File 
A
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.5 Å
  • R-Value Free: 0.238 
  • R-Value Work: 0.180 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 48.030α = 90.00
b = 86.390β = 100.70
c = 50.550γ = 90.00
Software Package:
Software NamePurpose
X-PLORrefinement
DENZOdata reduction
AMoREphasing
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2002-08-07
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance