Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Biological Assembly 2  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 2 assigned by authors.

Biological Assembly 3  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 3 generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 34.49 kDa 
• Atom Count: 2558 
• Residue Count: 283 
• Unique protein chains: 1

4BW7

Calmodulin in complex with strontium

• DOI: 10.2210/pdb4BW7/pdb

• Classification: METAL BINDING PROTEIN
• Organism(s): Homo sapiens
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2013-06-30 Released: 2014-01-15 
• Deposition Author(s): Kursula, P.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.81 Å
• R-Value Free: 0.251 
• R-Value Work: 0.205 
• R-Value Observed: 0.208 

Literature

Crystallographic Snapshots of Initial Steps in the Collapse of the Calmodulin Central Helix

Kursula, P.

(2014) Acta Crystallogr D Biol Crystallogr 70: 24

• PubMed: 24419375 
• DOI: 10.1107/S1399004713024437
• Primary Citation of Related Structures:  
  4BW7, 4BW8


• PubMed Abstract: 
  

Calmodulin is one of the most well characterized proteins and a widely used model system for calcium binding and large-scale protein conformational changes. Its long central helix is usually cut in half when a target peptide is bound. Here, two new crystal structures of calmodulin are presented, in which conformations possibly representing the first steps of calmodulin conformational collapse have been trapped. The central helix in the two structures is bent in the middle, causing a significant movement of the N- and C-terminal lobes with respect to one another. In both of the bent structures, a nearby polar side chain is inserted into the helical groove, disrupting backbone hydrogen bonding. The structures give an insight into the details of the factors that may be involved in the distortion of the central helix upon ligand peptide binding.

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Organizational Affiliation: 

Department of Biochemistry and Biocenter Oulu, University of Oulu, Oulu, Finland.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
CALMODULIN	A, C	149	Homo sapiens	Mutation(s): 0  Gene Names: CALM1, CALM, CAM, CAM1
Find proteins for P0DP23 (Homo sapiens) Explore P0DP23  Go to UniProtKB:  P0DP23
NIH Common Fund Data Resources
PHAROS:  P0DP23 GTEx:  ENSG00000198668

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SR	A, C	STRONTIUM ION Sr PWYYWQHXAPXYMF-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.81 Å
• R-Value Free: 0.251 
• R-Value Work: 0.205 
• R-Value Observed: 0.208 
• Space Group: P 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 24.34	α = 88.51
b = 53.94	β = 96.61
c = 59.37	γ = 93.96

Software Package:

Software Name	Purpose
PHENIX	refinement
XDS	data reduction
XSCALE	data scaling
PHASER	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2013-06-30 
• Released Date: 2014-01-15 
Deposition Author(s): Kursula, P.

Revision History 

• Version 1.0: 2014-01-15
  Type: Initial release
  
• Version 1.1: 2014-01-22
  Changes: Database references
• Version 2.0: 2018-01-17
  Changes: Atomic model, Data collection