1PPE

THE REFINED 2.0 ANGSTROMS X-RAY CRYSTAL STRUCTURE OF THE COMPLEX FORMED BETWEEN BOVINE BETA-TRYPSIN AND CMTI-I, A TRYPSIN INHIBITOR FROM SQUASH SEEDS (CUCURBITA MAXIMA): TOPOLOGICAL SIMILARITY OF THE SQUASH SEED INHIBITORS WITH THE CARBOXYPEPTIDASE A INHIBITOR FROM POTATOES


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Work: 0.151 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

The refined 2.0 A X-ray crystal structure of the complex formed between bovine beta-trypsin and CMTI-I, a trypsin inhibitor from squash seeds (Cucurbita maxima). Topological similarity of the squash seed inhibitors with the carboxypeptidase A inhibitor from potatoes

Bode, W.Greyling, H.J.Huber, R.Otlewski, J.Wilusz, T.

(1989) FEBS Lett. 242: 285-292


  • PubMed Abstract: 
  • The stoichiometric complex formed between bovine beta-trypsin and the Cucurbita maxima trypsin inhibitor I (CMTI-I) was crystallized and its X-ray crystal structure determined using Patterson search techniques. Its structure has been crystallographic ...

    The stoichiometric complex formed between bovine beta-trypsin and the Cucurbita maxima trypsin inhibitor I (CMTI-I) was crystallized and its X-ray crystal structure determined using Patterson search techniques. Its structure has been crystallographically refined to a final R value of 0.152 (6.0-2.0 A). CMTI-I is of ellipsoidal shape; it lacks helices or beta-sheets, but consists of turns and connecting short polypeptide stretches. The disulfide pairing is CYS-3I-20I, Cys-10I-22I and Cys-16I-28I. According to the polypeptide fold and disulfide connectivity its structure resembles that of the carboxypeptidase A inhibitor from potatoes. Thirteen of the 29 inhibitor residues are in direct contact with trypsin; most of them are in the primary binding segment Val-2I (P4)-Glu-9I (P4') which contains the reactive site bond Arg-5I-Ile-6I and is in a conformation observed also for other serine proteinase inhibitors.


    Related Citations: 
    • The Squash Family of Serine Proteinase Inhibitors. Amino Acid Sequences and Association Equilibrium Constants of Inhibitors from Squash, Summer Squash, Zucchini, and Cucumber Seeds
      Wieczorek, M.,Otlewski, J.,Cook, J.,Parks, K.,Leluk, J.,Wilimowska-Pelc, A.,Polanowski, A.,Wilusz, T.,Laskowski Junior, M.
      (1985) Biochem.Biophys.Res.Commun. 126: 646
    • Nuclear Magnetic Resonance Solution and X-Ray Structures of Squash Trypsin Inhibitor Exhibit the Same Conformation of the Proteinase Binding Loop
      Holak, T.A.,Bode, W.,Huber, R.,Otlewski, J.,Wilusz, T.
      (1989) J.Mol.Biol. 210: 649
    • Ligand Binding: Proteinase-Protein Inhibitor Interactions
      Bode, W.,Huber, R.
      (1991) Curr.Opin.Struct.Biol. 1: 45
    • Amino-Acid Sequence of Two Trypsin Isoinhibitors, Itd I and Itd III from Squash Seeds (Cucurbita Maxima)
      Wilusz, T.,Wieczorek, M.,Polanowski, A.,Denton, A.,Cook, J.,Laskowski Junior, M.
      (1983) Hoppe-Seyler's Z.Physiol.Chem. 364: 93
    • The Refined Crystal Structure of Bovine Beta-Trypsin at 1.8 Angstroms Resolution. Crystallographic Refinement, Calcium Binding Site, Benzamidine Binding Site and Active Site at Ph 7.0
      Bode, W.,Schwager, P.
      (1975) J.Mol.Biol. 98: 693


    Organizational Affiliation

    Max-Planck-Institut für Biochemie, Martinsried, FRG.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
TRYPSIN
E
223Bos taurusEC: 3.4.21.4
Find proteins for P00760 (Bos taurus)
Go to UniProtKB:  P00760
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
TRYPSIN INHIBITOR CMTI-I
I
29Cucurbita maximaN/A
Find proteins for P01074 (Cucurbita maxima)
Go to UniProtKB:  P01074
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Work: 0.151 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 59.280α = 90.00
b = 55.470β = 90.00
c = 74.590γ = 90.00
Software Package:
Software NamePurpose
EREFrefinement
SQUASHphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 1991-10-24 
  • Released Date: 1994-01-31 
  • Deposition Author(s): Bode, W., Huber, R.

Revision History 

  • Version 1.0: 1994-01-31
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance