1B0C

EVIDENCE OF A COMMON DECAMER IN THREE CRYSTAL STRUCTURES OF BPTI, CRYSTALLIZED FROM THIOCYANATE, CHLORIDE OR SULFATE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.223 
  • R-Value Work: 0.198 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

The BPTI decamer observed in acidic pH crystal forms pre-exists as a stable species in solution.

Hamiaux, C.Perez, J.Prange, T.Veesler, S.Ries-Kautt, M.Vachette, P.

(2000) J.Mol.Biol. 297: 697-712

  • DOI: 10.1006/jmbi.2000.3584
  • Primary Citation of Related Structures:  1BZ5

  • PubMed Abstract: 
  • Bovine pancreatic trypsin inhibitor (BPTI) crystallizes under acidic pH conditions in the presence of thiocyanate, chloride and sulfate ions, yielding three different polymorphs in P2(1), P6(4)22 and P6(3)22 space groups, respectively. In all three c ...

    Bovine pancreatic trypsin inhibitor (BPTI) crystallizes under acidic pH conditions in the presence of thiocyanate, chloride and sulfate ions, yielding three different polymorphs in P2(1), P6(4)22 and P6(3)22 space groups, respectively. In all three crystal forms, the same decamer is found in the packing (ten BPTI molecules organized through two perpendicular 2-fold and 5-fold axes as a well-defined and compact object) in contrast to the monomeric crystal forms observed at basic pH conditions. The crystallization of BPTI under acidic conditions (pH 4.5) was investigated by small angle X-ray scattering with both under- and supersaturated BPTI solutions. Data showed the oligomerization of BPTI molecules under all investigated conditions. Accordingly, various mixtures of discrete oligomers (n=1 to 10) were considered. Calculated scattering curves were obtained using models based on the crystallographic structures, and the experimental patterns were analyzed as a linear combination of the model curves using a non-linear curve fitting procedure. The results, confirmed by gel filtration experiments, unambiguously demonstrate the co-existence of two different BPTI particles in solution: a monomer and a decamer, with no evidence of any other intermediates. Moreover, using both approaches, the fraction of decamers was found to increase with increasing salt concentration, even beyond the solubility curve. We therefore propose that at acidic pH, BPTI crystallizes following a two step process: decamers are first built in under- and supersaturated solutions, upon which crystal growth proceeds by decamer stacking. Indeed, those BPTI crystals should best be described as "BPTI decamer" crystals.


    Related Citations: 
    • Decamers Observed in the Crystals of Bovine Panreatic Trypsin Inhibitor
      Lubkowski, J.,Wlodawer, A.
      (1999) Acta Crystallogr.,Sect.D 55: 335
    • The Decameric Structure of Bovine Pancreatic Trypsin Inhibitor (Bpti) Crystallized from Thiocyanate at 2.7A Resolution
      Hamiaux, C.,Prange, T.,Ries-Kautt, M.,Ducruix, A.,Lafont, S.,Astier, J.P.,Veesler, S.
      (1999) Acta Crystallogr.,Sect.D 55: 103


    Organizational Affiliation

    LURE (CNRS-CEA-MENRT), Centre Universitaire Paris-Sud, Bât 209 D, B. P. 34, Orsay Cedex, 91898, France. hamiaux@lure.u-psud.fr




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PROTEIN (PANCREATIC TRYPSIN INHIBITOR)
A, B, C, D, E
58Bos taurusN/A
Find proteins for P00974 (Bos taurus)
Go to UniProtKB:  P00974
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.223 
  • R-Value Work: 0.198 
  • Space Group: P 64 2 2
Unit Cell:
Length (Å)Angle (°)
a = 95.470α = 90.00
b = 95.470β = 90.00
c = 159.690γ = 120.00
Software Package:
Software NamePurpose
ROTAVATAdata reduction
Agrovatadata scaling
ROTAVATAdata scaling
X-PLORrefinement
MOSFLMdata reduction
Agrovatadata reduction
AMoREphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1998-11-11
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2017-10-04
    Type: Refinement description