Biological Assembly 1  

 3D View: Structure | Electron Density

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

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

Macromolecule Content

• Total Structure Weight: 26.78 kDa 
• Atom Count: 2502 
• Residue Count: 229 
• Unique protein chains: 1

5OXA

Structure of the S205A mutant of the Cyan Fluorescent Protein Cerulean at pH 7.0

• DOI: 10.2210/pdb5OXA/pdb

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


• Deposited: 2017-09-06 Released: 2017-11-29 
• Deposition Author(s): Gotthard, G., von Stetten, D., Clavel, D., Noirclerc-Savoye, M., Royant, A.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.16 Å
• R-Value Free: 0.139 
• R-Value Work: 0.116 
• R-Value Observed: 0.117 

Literature

Chromophore Isomer Stabilization Is Critical to the Efficient Fluorescence of Cyan Fluorescent Proteins.

Gotthard, G., von Stetten, D., Clavel, D., Noirclerc-Savoye, M., Royant, A.

(2017) Biochemistry 56: 6418-6422

• PubMed: 29148725 
• DOI: 10.1021/acs.biochem.7b01088
• Primary Citation of Related Structures:  
  5OX9, 5OX8, 5OXA, 5OXC, 5OXB


• PubMed Abstract: 
  

ECFP, the first usable cyan fluorescent protein (CFP), was obtained by adapting the tyrosine-based chromophore environment in green fluorescent protein to that of a tryptophan-based one. This first-generation CFP was superseded by the popular Cerulean, CyPet, and SCFP3A that were engineered by rational and random mutagenesis, yet the latter CFPs still exhibit suboptimal properties of pH sensitivity and reversible photobleaching behavior. These flaws were serendipitously corrected in the third-generation CFP mTurquoise and its successors without an obvious rationale. We show here that the evolution process had unexpectedly remodeled the chromophore environment in second-generation CFPs so they would accommodate a different isomer, whose formation is favored by acidic pH or light irradiation and which emits fluorescence much less efficiently. Our results illustrate how fluorescent protein engineering based solely on fluorescence efficiency optimization may affect other photophysical or physicochemical parameters and provide novel insights into the rational evolution of fluorescent proteins with a tryptophan-based chromophore.

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Organizational Affiliation: 

Univ. Grenoble Alpes, CNRS, CEA, IBS (Institut de Biologie Structurale), F-38000 Grenoble, France.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Green fluorescent protein	A	237	Aequorea victoria	Mutation(s): 6  Gene Names: GFP
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
B2H	A	L-PEPTIDE LINKING	C17 H20 N4 O4		THR, TRP, GLY

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.16 Å
• R-Value Free: 0.139 
• R-Value Work: 0.116 
• R-Value Observed: 0.117 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 50.96	α = 90
b = 63.32	β = 90
c = 69.33	γ = 90

Software Package:

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

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2017-09-06 
• Released Date: 2017-11-29 
Deposition Author(s): Gotthard, G., von Stetten, D., Clavel, D., Noirclerc-Savoye, M., Royant, A.

Revision History 

• Version 1.0: 2017-11-29
  Type: Initial release
  
• Version 1.1: 2017-12-06
  Changes: Database references
• Version 1.2: 2017-12-20
  Changes: Database references