1EMB

GREEN FLUORESCENT PROTEIN (GFP) FROM AEQUOREA VICTORIA, GLN 80 REPLACED WITH ARG


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.13 Å
  • R-Value Free: 0.250 
  • R-Value Work: 0.196 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural basis for dual excitation and photoisomerization of the Aequorea victoria green fluorescent protein.

Brejc, K.Sixma, T.K.Kitts, P.A.Kain, S.R.Tsien, R.Y.Ormo, M.Remington, S.J.

(1997) Proc.Natl.Acad.Sci.USA 94: 2306-2311


  • PubMed Abstract: 
  • The 2.1-A resolution crystal structure of wild-type green fluorescent protein and comparison of it with the recently determined structure of the Ser-65 --> Thr (S65T) mutant explains the dual wavelength absorption and photoisomerization properties of ...

    The 2.1-A resolution crystal structure of wild-type green fluorescent protein and comparison of it with the recently determined structure of the Ser-65 --> Thr (S65T) mutant explains the dual wavelength absorption and photoisomerization properties of the wild-type protein. The two absorption maxima are caused by a change in the ionization state of the chromophore. The equilibrium between these states appears to be governed by a hydrogen bond network that permits proton transfer between the chromophore and neighboring side chains. The predominant neutral form of the fluorophore maximally absorbs at 395 nm. It is maintained by the carboxylate of Glu-222 through electrostatic repulsion and hydrogen bonding via a bound water molecule and Ser-205. The ionized form of the fluorophore, absorbing at 475 nm, is present in a minor fraction of the native protein. Glu-222 donates its charge to the fluorophore by proton abstraction through a hydrogen bond network, involving Ser-205 and bound water. Further stabilization of the ionized state of the fluorophore occurs through a rearrangement of the side chains of Thr-203 and His-148. UV irradiation shifts the ratio of the two absorption maxima by pumping a proton relay from the neutral chromophore's excited state to Glu-222. Loss of the Ser-205-Glu-222 hydrogen bond and isomerization of neutral Glu-222 explains the slow return to the equilibrium dark-adapted state of the chromophore. In the S65T structure, steric hindrance by the extra methyl group stabilizes a hydrogen bonding network, which prevents ionization of Glu-222. Therefore the fluorophore is permanently ionized, causing only a 489-nm excitation peak. This new understanding of proton redistribution in green fluorescent protein should enable engineering of environmentally sensitive fluorescent indicators and UV-triggered fluorescent markers of protein diffusion and trafficking in living cells.


    Related Citations: 
    • Crystal Structure of the Aequorea Victoria Green Fluorescent Protein
      Ormo, M.,Cubitt, A.B.,Kallio, K.,Gross, L.A.,Tsien, R.Y.,Remington, S.J.
      (1996) Science 273: 1392


    Organizational Affiliation

    Netherlands Cancer Institute, Department of Molecular Carcinogenesis, Amsterdam.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
GREEN FLUORESCENT PROTEIN
A
238Aequorea victoriaGene Names: GFP
Find proteins for P42212 (Aequorea victoria)
Go to UniProtKB:  P42212
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
CRO
Query on CRO
A
L-PEPTIDE LINKINGC15 H17 N3 O5THR, TYR, GLY
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.13 Å
  • R-Value Free: 0.250 
  • R-Value Work: 0.196 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 51.900α = 90.00
b = 63.200β = 90.00
c = 68.800γ = 90.00
Software Package:
Software NamePurpose
MOSFLMdata reduction
TNTphasing
CCP4data scaling
TNTrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 1997-01-08 
  • Released Date: 1997-06-16 
  • Deposition Author(s): Brejc, K., Sixma, T.

Revision History 

  • Version 1.0: 1997-06-16
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance