4AR7

X-ray structure of the cyan fluorescent protein mTurquoise

• PDB DOI: https://doi.org/10.2210/pdb4AR7/pdb

• Classification: FLUORESCENT PROTEIN
• Organism(s): Aequorea victoria
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): Yes 


• Deposited: 2012-04-21 Released: 2012-08-08 
• Deposition Author(s): von Stetten, D., Noirclerc-Savoye, M., Goedhart, J., Gadella, T.W.J., Royant, A.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.23 Å
• R-Value Free: 0.166 
• R-Value Work: 0.143 
• R-Value Observed: 0.144 

Starting Model: experimental

Literature

Structure of a Fluorescent Protein from Aequorea Victoria Bearing the Obligate-Monomer Mutation A206K.

von Stetten, D., Noirclerc-Savoye, M., Goedhart, J., Gadella, T.W.J.J., Royant, A.

(2012) Acta Crystallogr Sect F Struct Biol Cryst Commun 68: 878

• PubMed: 22869113 
• DOI: https://doi.org/10.1107/S1744309112028667
• Primary Citation of Related Structures:  
  4AR7


• PubMed Abstract: 
  

  The green fluorescent protein (GFP) from the jellyfish Aequoria victoria has been shown to dimerize at high concentrations, which could lead to artefacts in imaging experiments. To ensure a truly monomeric state, an A206K mutation has been introduced into most of its widely used variants, with minimal effect on the spectroscopic properties. Here, the first structure of one of these variants, the cyan fluorescent protein mTurquoise, is presented and compared with that of its dimeric version mTurquoise-K206A. No significant structural change is detected in the chromophore cavity, reinforcing the notion that this mutation is spectroscopically silent and validating that the structural analysis performed on dimeric mutants also applies to monomeric versions. Finally, it is explained why cyan versions of GFP containing the Y66W and N146I mutations do not require the A206K mutation to prevent dimerization at high concentrations.

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Organizational Affiliation: 

Structural Biology Group, European Synchrotron Radiation Facility, 6 Rue Jules Horowitz, 38043 Grenoble, France.

Biological Assembly 1  

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

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

Macromolecule Content

• Total Structure Weight: 27.72 kDa 
• Atom Count: 2,039 
• Modelled Residue Count: 225 
• Deposited Residue Count: 243 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
GREEN FLUORESCENT PROTEIN	A	243	Aequorea victoria	Mutation(s): 10
UniProt
Find proteins for P42212 (Aequorea victoria) Explore P42212  Go to UniProtKB:  P42212

Small Molecules

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
SWG	A	L-PEPTIDE LINKING	C16 H16 N4 O4		SER, TRP, GLY

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.23 Å
• R-Value Free: 0.166 
• R-Value Work: 0.143 
• R-Value Observed: 0.144 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 51.452	α = 90
b = 62.558	β = 90
c = 69.543	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
XDS	data reduction
SCALA	data scaling
REFMAC	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2012-08-08 
Deposition Author(s): von Stetten, D., Noirclerc-Savoye, M., Goedhart, J., Gadella, T.W.J., Royant, A.

Revision History  

• Version 1.0: 2012-08-08
  Type: Initial release
  
• Version 1.1: 2012-08-15
  Changes: Database references
• Version 1.2: 2017-12-20
  Changes: Database references
• Version 1.3: 2019-10-23
  Changes: Data collection, Database references, Derived calculations, Other
• Version 1.4: 2023-12-20
  Changes: Data collection, Database references, Derived calculations, Refinement description
• Version 1.5: 2024-10-23
  Changes: Structure summary