1NP8

18-k C-terminally trunucated small subunit of calpain


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.239 
  • R-Value Work: 0.196 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

A second binding site revealed by C-terminal truncation of calpain small subunit, a penta-EF-hand protein

Leinala, E.K.Arthur, J.S.Grochulski, P.Davies, P.L.Elce, J.S.Jia, Z.

(2003) PROTEINS: STRUCT.,FUNCT.,GENET. 53: 649-655

  • DOI: 10.1002/prot.10453

  • PubMed Abstract: 
  • The subunits in calpain and in the related penta-EF-hand (PEF) proteins are bound through contacts between the unpaired EF-hand 5 from each subunit. To study subunit binding further, a tetra-EF-hand 18 kDa N- and C-terminally truncated form of the ca ...

    The subunits in calpain and in the related penta-EF-hand (PEF) proteins are bound through contacts between the unpaired EF-hand 5 from each subunit. To study subunit binding further, a tetra-EF-hand 18 kDa N- and C-terminally truncated form of the calpain small subunit was prepared (18k). This protein does not combine with the calpain large subunit to form active calpain, but forms homodimers in solution, as shown by ultracentrifugation. The X-ray structure of the 18k protein in the presence of cadmium was solved to a resolution of 2.0 A. The structure of the monomer is almost identical to the known structure of the calpain small subunit, but the 18k protein forms an oligomer in the crystal by the use of two binding sites. One of these sites is an artefact arising from the C-terminal truncation, but the other is a naturally occurring site that is fully exposed to water in intact purified calpain. The characteristics of this site suggest that it may be important in binding other protein modulators involved in the regulation of calpain and of PEF proteins.


    Organizational Affiliation

    Department of Biochemistry, Queen's University, Kingston, Ontario, Canada.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Calcium-dependent protease, small subunit
A, B
159Rattus norvegicusGene Names: Capns1 (Capn4, Css1)
Find proteins for Q64537 (Rattus norvegicus)
Go to UniProtKB:  Q64537
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CD
Query on CD

Download SDF File 
Download CCD File 
A, B
CADMIUM ION
Cd
WLZRMCYVCSSEQC-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.239 
  • R-Value Work: 0.196 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 58.040α = 90.00
b = 67.570β = 90.00
c = 75.070γ = 90.00
Software Package:
Software NamePurpose
DENZOdata reduction
AMoREphasing
CNSrefinement
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-11-18
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance