Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 22258.05 
• Atom Count: 1483 
• Residue Count: 196 
• Unique protein chains: 1

2RGI

Crystal structure of Ca2+-free S100A2 at 1.6 A resolution

• DOI: 10.2210/pdb2RGI/pdb

• Classification: METAL BINDING PROTEIN
• Organism(s): Homo sapiens
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): 4 


• Deposited: 2007-10-03 Released: 2008-01-29 
• Deposition Author(s): Koch, M., Diez, J., Fritz, G.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.6 Å
• R-Value Free: 0.227 
• R-Value Work: 0.186 

Literature

Crystal structure of Ca2+ -free S100A2 at 1.6-A resolution.

Koch, M., Diez, J., Fritz, G.

(2008) J.Mol.Biol. 378: 931-940

• PubMed: 18394645 
• DOI: 10.1016/j.jmb.2008.03.019


• PubMed Abstract: 
  

S100A2 is an EF hand-containing Ca(2+)-binding protein of the family of S100 proteins. The protein is localized exclusively in the nucleus and is involved in cell cycle regulation. It attracted most interest by its function as a tumor suppressor via p53 interaction. We determined the crystal structure of homodimeric S100A2 in the Ca(2+)-free state at 1.6-A resolution. The structure revealed structural differences between subunits A and B, especially in the conformation of a loop that connects the N- and C-terminal EF hands and represents a part of the target-binding site in S100 proteins. Analysis of the hydrogen bonding network and molecular dynamics calculations indicate that one of the two observed conformations is more stable. The structure revealed Na(+) bound to each N-terminal EF hand of both subunits coordinated by oxygen atoms of the backbone carbonyl and water molecules. Comparison with the structures of Ca(2+)-free S100A3 and S100A6 suggests that Na(+) might occupy the S100-specific EF hand in the Ca(2+)-free state.

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Organizational Affiliation: 

Fachbereich Biologie, Universität Konstanz, Postfach M665, Universitätsstrasse 10, 78457 Konstanz, Germany.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
Protein S100-A2	A, B	98	Homo sapiens	Mutation(s): 4  Gene Names: S100A2 (S100L)
Find proteins for P29034 (Homo sapiens) Go to Gene View: S100A2 Go to UniProtKB:  P29034

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram & Interactions
NA	A, B	SODIUM ION Na FKNQFGJONOIPTF-UHFFFAOYSA-N
IPA	A	ISOPROPYL ALCOHOL 2-PROPANOL C3 H8 O KFZMGEQAYNKOFK-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.6 Å
• R-Value Free: 0.227 
• R-Value Work: 0.186 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length (Å)	Angle (°)
a = 43.516	α = 90.00
b = 57.820	β = 90.00
c = 59.794	γ = 90.00

Software Package:

Software Name	Purpose
XSCALE	data scaling
XDS	data reduction
REFMAC	refinement
PDB_EXTRACT	data extraction
PHASER	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2007-10-03 
• Released Date: 2008-01-29 
• Deposition Author(s): Koch, M., Diez, J., Fritz, G.

Revision History 

• Version 1.0: 2008-01-29
  Type: Initial release
• Version 1.1: 2011-07-13
  Type: Version format compliance