3PD1

Caspase-3 K242A


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.62 Å
  • R-Value Free: 0.226 
  • R-Value Work: 0.208 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Thermodynamic, enzymatic and structural effects of removing a salt bridge at the base of loop 4 in (pro)caspase-3.

Walters, J.Swartz, P.Mattos, C.Clark, A.C.

(2011) Arch Biochem Biophys 508: 31-38

  • DOI: 10.1016/j.abb.2011.01.011
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • Interactions between loops 2, 2' and 4, known as the loop bundle, stabilize the active site of caspase-3. Loop 4 (L4) is of particular interest due to its location between the active site and the dimer interface. We have disrupted a salt bridge betwe ...

    Interactions between loops 2, 2' and 4, known as the loop bundle, stabilize the active site of caspase-3. Loop 4 (L4) is of particular interest due to its location between the active site and the dimer interface. We have disrupted a salt bridge between K242 and E246 at the base of L4 to determine its role in overall conformational stability and in maintaining the active site environment. Stability measurements show that only the K242A single mutant decreases stability of the dimer, whereas both single mutants and the double mutant demonstrate much lower activity compared to wild-type caspase-3. Structural studies of the caspase-3 variants show the involvement of K242 in hydrophobic interactions that stabilize helix 5, near the dimer interface, and the role of E246 appears to be to neutralize the positive charge of K242 within the hydrophobic cluster. Overall, the results suggest E246 and K242 are important in procaspase-3 for their interaction with neighboring residues, not with one another. Conversely, formation of the K242-E246 salt bridge in caspase-3 is needed for an accurate, stable conformation of loop L4 and proper active site formation in the mature enzyme.


    Organizational Affiliation

    Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC 27695-7622, USA.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Caspase-3A250Homo sapiensMutation(s): 1 
Gene Names: CASP3CPP32
EC: 3.4.22.56
Find proteins for P42574 (Homo sapiens)
Explore P42574 
Go to UniProtKB:  P42574
NIH Common Fund Data Resources
PHAROS  P42574
Protein Feature View
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  • Reference Sequence
  • Find similar proteins by: Sequence   |   Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Inhibitor Ac-DEVD-CMKB6N/AMutation(s): 0 
Protein Feature View
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  • Reference Sequence
Small Molecules
Biologically Interesting Molecules 1 Unique
IDChainsNameType/Class2D Diagram3D Interactions
PRD_000238 (0DD)
Query on PRD_000238
BAc-Asp-Glu-Val-Asp-CMKP /  Inhibitor

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Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.62 Å
  • R-Value Free: 0.226 
  • R-Value Work: 0.208 
  • Space Group: I 2 2 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 68.67α = 90
b = 84.53β = 90
c = 96.17γ = 90
Software Package:
Software NamePurpose
HKL-2000data collection
CNSrefinement
HKL-2000data reduction
HKL-2000data scaling
CNSphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-02-23
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2011-11-16
    Changes: Atomic model
  • Version 1.3: 2013-02-27
    Changes: Other