1C4F

GREEN FLUORESCENT PROTEIN S65T AT PH 4.6


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.25 Å
  • R-Value Work: 0.193 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Structural and spectral response of green fluorescent protein variants to changes in pH.

Elsliger, M.A.Wachter, R.M.Hanson, G.T.Kallio, K.Remington, S.J.

(1999) Biochemistry 38: 5296-5301

  • DOI: 10.1021/bi9902182
  • Primary Citation of Related Structures:  1EMG

  • PubMed Abstract: 
  • The green fluorescent protein (GFP) from the jellyfish Aequorea victoria has become a useful tool in molecular and cell biology. Recently, it has been found that the fluorescence spectra of most mutants of GFP respond rapidly and reversibly to pH var ...

    The green fluorescent protein (GFP) from the jellyfish Aequorea victoria has become a useful tool in molecular and cell biology. Recently, it has been found that the fluorescence spectra of most mutants of GFP respond rapidly and reversibly to pH variations, making them useful as probes of intracellular pH. To explore the structural basis for the titration behavior of the popular GFP S65T variant, we determined high-resolution crystal structures at pH 8.0 and 4.6. The structures revealed changes in the hydrogen bond pattern with the chromophore, suggesting that the pH sensitivity derives from protonation of the chromophore phenolate. Mutations were designed in yellow fluorescent protein (S65G/V68L/S72A/T203Y) to change the solvent accessibility (H148G) and to modify polar groups (H148Q, E222Q) near the chromophore. pH titrations of these variants indicate that the chromophore pKa can be modulated over a broad range from 6 to 8, allowing for pH determination from pH 5 to pH 9. Finally, mutagenesis was used to raise the pKa from 6.0 (S65T) to 7.8 (S65T/H148D). Unlike other variants, S65T/H148D exhibits two pH-dependent excitation peaks for green fluorescence with a clean isosbestic point. This raises the interesting possibility of using fluorescence at this isosbestic point as an internal reference. Practical real time in vivo applications in cell and developmental biology are proposed.


    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
    • Crystal Structure and Photodynamic Behavior of the Blue Emission Variant Y66H/ Y145F of Green Fluorescent Protein
      Wachter, R.M.,King, B.A.,Heim, R.,Kallio, K.,Tsien, R.Y.,Boxer, S.G.,Remington, S.J.
      (1997) Biochemistry 36: 9759
    • Structural Basis of Spectral Shifts in the Yellow-Emission Variants of Green Fluorescent Protein
      Wachter, R.M.,Elsliger, M.A.,Kallio, K.,Hanson, G.T.,Remington, S.J.
      (1998) Structure 6: 1267


    Organizational Affiliation

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




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: 2.25 Å
  • R-Value Work: 0.193 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 51.934α = 90.00
b = 62.898β = 90.00
c = 69.172γ = 90.00
Software Package:
Software NamePurpose
PROTEINmodel building
CCP4phasing
DENZOdata reduction
TNTrefinement
CCP4model building
SCALEPACKdata scaling
PROTEINphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1999-08-31
    Type: Initial release
  • Version 1.1: 2007-10-16
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2017-10-04
    Type: Advisory