IrisFP fluorescent protein in its green form, cis conformation

Experimental Data Snapshot

  • Resolution: 1.80 Å
  • R-Value Free: 0.219 
  • R-Value Work: 0.185 
  • R-Value Observed: 0.187 

wwPDB Validation   3D Report Full Report

This is version 3.1 of the entry. See complete history


Structural Characterization of Irisfp, an Optical Highlighter Undergoing Multiple Photo-Induced Transformations.

Adam, V.Lelimousin, M.Boehme, S.Desfonds, G.Nienhaus, K.Field, M.J.Wiedenmann, J.Mcsweeney, S.Nienhaus, G.U.Bourgeois, D.

(2008) Proc Natl Acad Sci U S A 105: 18343

  • DOI: https://doi.org/10.1073/pnas.0805949105
  • Primary Citation of Related Structures:  
    2VVH, 2VVI, 2VVJ

  • PubMed Abstract: 

    Photoactivatable fluorescent proteins (FPs) are powerful fluorescent highlighters in live cell imaging and offer perspectives for optical nanoscopy and the development of biophotonic devices. Two types of photoactivation are currently being distinguished, reversible photoswitching between fluorescent and nonfluorescent forms and irreversible photoconversion. Here, we have combined crystallography and (in crystallo) spectroscopy to characterize the Phe-173-Ser mutant of the tetrameric variant of EosFP, named IrisFP, which incorporates both types of phototransformations. In its green fluorescent state, IrisFP displays reversible photoswitching, which involves cis-trans isomerization of the chromophore. Like its parent protein EosFP, IrisFP also photoconverts irreversibly to a red-emitting state under violet light because of an extension of the conjugated pi-electron system of the chromophore, accompanied by a cleavage of the polypeptide backbone. The red form of IrisFP exhibits a second reversible photoswitching process, which may also involve cis-trans isomerization of the chromophore. Therefore, IrisFP displays altogether 3 distinct photoactivation processes. The possibility to engineer and precisely control multiple phototransformations in photoactivatable FPs offers exciting perspectives for the extension of the fluorescent protein toolkit.

  • Organizational Affiliation

    European Synchrotron Radiation Facility, 6 Rue Jules Horowitz, BP 220, 38043 Grenoble Cedex, France.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Green to red photoconvertible GFP-like protein EosFP
A, B, C, D
226Lobophyllia hemprichiiMutation(s): 3 
Find proteins for Q5S6Z9 (Lobophyllia hemprichii)
Explore Q5S6Z9 
Go to UniProtKB:  Q5S6Z9
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ5S6Z9
Sequence Annotations
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
Query on SO4

Download Ideal Coordinates CCD File 
E [auth A]
F [auth A]
G [auth A]
I [auth A]
J [auth B]
E [auth A],
F [auth A],
G [auth A],
I [auth A],
J [auth B],
K [auth B],
L [auth B],
M [auth B],
O [auth C],
P [auth C],
Q [auth C],
S [auth D],
T [auth D],
U [auth D],
V [auth D]
O4 S
Query on SO3

Download Ideal Coordinates CCD File 
H [auth A],
N [auth B],
R [auth C],
W [auth D]
O3 S
Modified Residues  1 Unique
IDChains TypeFormula2D DiagramParent
Query on 5SQ
A, B, C, D
Experimental Data & Validation

Experimental Data

  • Resolution: 1.80 Å
  • R-Value Free: 0.219 
  • R-Value Work: 0.185 
  • R-Value Observed: 0.187 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 86.34α = 90
b = 96.55β = 90
c = 139.83γ = 90
Software Package:
Software NamePurpose
XDSdata reduction
XSCALEdata scaling

Structure Validation

View Full Validation Report

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2008-11-11
    Type: Initial release
  • Version 1.1: 2011-05-08
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2019-03-06
    Changes: Data collection, Derived calculations, Experimental preparation, Other
  • Version 1.4: 2019-10-23
    Changes: Data collection, Database references, Other
  • Version 2.0: 2021-09-01
    Changes: Advisory, Atomic model, Data collection, Database references, Derived calculations, Non-polymer description, Polymer sequence, Source and taxonomy, Structure summary
  • Version 3.0: 2023-11-15
    Changes: Advisory, Atomic model, Data collection, Derived calculations
  • Version 3.1: 2023-12-13
    Changes: Refinement description