3BXA

Monomeric Far-red Fluorescent Protein mKate Crystallized at pH 4.2


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.75 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.180 
  • R-Value Observed: 0.182 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

A Crystallographic Study of Bright Far-Red Fluorescent Protein mKate Reveals pH-induced cis-trans Isomerization of the Chromophore.

Pletnev, S.Shcherbo, D.Chudakov, D.M.Pletneva, N.Merzlyak, E.M.Wlodawer, A.Dauter, Z.Pletnev, V.

(2008) J Biol Chem 283: 28980-28987

  • DOI: https://doi.org/10.1074/jbc.M800599200
  • Primary Citation of Related Structures:  
    3BX9, 3BXA, 3BXB, 3BXC

  • PubMed Abstract: 

    The far-red fluorescent protein mKate (lambda(ex), 588 nm; lambda(em), 635 nm; chromophore-forming triad Met(63)-Tyr(64)-Gly(65)), originating from wild-type red fluorescent progenitor eqFP578 (sea anemone Entacmaea quadricolor), is monomeric and characterized by the pronounced pH dependence of fluorescence, relatively high brightness, and high photostability. The protein has been crystallized at a pH ranging from 2 to 9 in three space groups, and four structures have been determined by x-ray crystallography at the resolution of 1.75-2.6 A. The pH-dependent fluorescence of mKate has been shown to be due to reversible cis-trans isomerization of the chromophore phenolic ring. In the non-fluorescent state at pH 2.0, the chromophore of mKate is in the trans-isomeric form. The weakly fluorescent state of the protein at pH 4.2 is characterized by a mixture of trans and cis isomers. The chromophore in a highly fluorescent state at pH 7.0/9.0 adopts the cis form. Three key residues, Ser(143), Leu(174), and Arg(197) residing in the vicinity of the chromophore, have been identified as being primarily responsible for the far-red shift in the spectra. A group of residues consisting of Val(93), Arg(122), Glu(155), Arg(157), Asp(159), His(169), Ile(171), Asn(173), Val(192), Tyr(194), and Val(216), are most likely responsible for the observed monomeric state of the protein in solution.


  • Organizational Affiliation

    Macromolecular Crystallography Laboratory, NCI, National Institutes of Health, Argonne, Illinois 60439, USA. svp@ncifcrf.gov


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Far-red fluorescent protein mKate
A, B
243Entacmaea quadricolorMutation(s): 0 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
CIT
Query on CIT

Download Ideal Coordinates CCD File 
C [auth B]CITRIC ACID
C6 H8 O7
KRKNYBCHXYNGOX-UHFFFAOYSA-N
Modified Residues  1 Unique
IDChains TypeFormula2D DiagramParent
NRQ
Query on NRQ
A, B
L-PEPTIDE LINKINGC16 H17 N3 O4 SMET, TYR, GLY
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.75 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.180 
  • R-Value Observed: 0.182 
  • Space Group: I 4
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 98.181α = 90
b = 98.181β = 90
c = 106.452γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
REFMACrefinement
PDB_EXTRACTdata extraction
SERGUIdata collection
HKL-2000data reduction
HKL-2000data scaling
MOLREPphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2008-07-22
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Derived calculations, Version format compliance
  • Version 1.2: 2017-10-25
    Changes: Refinement description