2QLE

GFP/S205V mutant


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.59 Å
  • R-Value Free: 0.256 
  • R-Value Work: 0.176 
  • R-Value Observed: 0.176 

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

An alternative excited-state proton transfer pathway in green fluorescent protein variant S205V.

Shu, X.Leiderman, P.Gepshtein, R.Smith, N.R.Kallio, K.Huppert, D.Remington, S.J.

(2007) Protein Sci 16: 2703-2710

  • DOI: https://doi.org/10.1110/ps.073112007
  • Primary Citation of Related Structures:  
    2QLE

  • PubMed Abstract: 

    Wild-type green fluorescent protein (wt-GFP) has a prominent absorbance band centered at approximately 395 nm, attributed to the neutral chromophore form. The green emission arising upon excitation of this band results from excited-state proton transfer (ESPT) from the chromophore hydroxyl, through a hydrogen-bond network proposed to consist of a water molecule and Ser205, to Glu222. Although evidence for Glu222 as a terminal proton acceptor has already been obtained, no evidence for the participation of Ser205 in the proton transfer process exists. To examine the role of Ser205 in the proton transfer, we mutated Ser205 to valine. However, the derived GFP variant S205V, upon excitation at 400 nm, still produces green fluorescence. Time-resolved emission spectroscopy suggests that ESPT contributes to the green fluorescence, and that the proton transfer takes place approximately 30 times more slowly than in wt-GFP. The crystal structure of S205V reveals rearrangement of Glu222 and Thr203, forming a new hydrogen-bonding network. We propose this network to be an alternative ESPT pathway with distinctive features that explain the significantly slowed rate of proton transfer. In support of this proposal, the double mutant S205V/T203V is shown to be a novel blue fluorescent protein containing a tyrosine-based chromophore, yet is incapable of ESPT. The results have implications for the detailed mechanism of ESPT and the photocycle of wt-GFP, in particular for the structures of spectroscopically identified intermediates in the cycle.


  • Organizational Affiliation

    Institute of Molecular Biology and Department of Physics, University of Oregon, Eugene, Oregon 97403-1229, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Green fluorescent protein
A, B, C, D
236Aequorea victoriaMutation(s): 3 
Gene Names: GFP
UniProt
Find proteins for Q8GHE2 (Azotobacter vinelandii)
Explore Q8GHE2 
Go to UniProtKB:  Q8GHE2
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ8GHE2
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.59 Å
  • R-Value Free: 0.256 
  • R-Value Work: 0.176 
  • R-Value Observed: 0.176 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 54.832α = 90
b = 151.496β = 110.23
c = 59.729γ = 90
Software Package:
Software NamePurpose
HKL-2000data collection
TNTrefinement
HKL-2000data scaling
TNTphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2008-02-12
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2018-06-27
    Changes: Data collection, Database references, Derived calculations, Source and taxonomy, Structure summary
  • Version 1.3: 2023-08-30
    Changes: Data collection, Database references, Derived calculations, Refinement description
  • Version 1.4: 2023-11-15
    Changes: Data collection