2ZMW

Crystal Structure of Monomeric Kusabira-Orange (MKO), Orange-Emitting GFP-like Protein, at pH 6.0


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.232 
  • R-Value Work: 0.197 
  • R-Value Observed: 0.197 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Structural Characterization of a Thiazoline-Containing Chromophore in an Orange Fluorescent Protein, Monomeric Kusabira Orange

Kikuchi, A.Fukumura, E.Karasawa, S.Mizuno, H.Miyawaki, A.Shiro, Y.

(2008) Biochemistry 47: 11573-11580

  • DOI: 10.1021/bi800727v
  • Primary Citation of Related Structures:  
    2ZMU, 2ZMW

  • PubMed Abstract: 
  • Monomeric Kusabira Orange (mKO) is a green fluorescent protein (GFP)-like protein that emits orange light at a peak of 559 nm. We analyzed its X-ray structure at 1.65 A and found a novel three-ring chromophore that developed autocatalytically from a Cys65-Tyr66-Glu67 tripeptide in which the side chain of Cys65 formed the third 2-hydroxy-3-thiazoline ring ...

    Monomeric Kusabira Orange (mKO) is a green fluorescent protein (GFP)-like protein that emits orange light at a peak of 559 nm. We analyzed its X-ray structure at 1.65 A and found a novel three-ring chromophore that developed autocatalytically from a Cys65-Tyr66-Glu67 tripeptide in which the side chain of Cys65 formed the third 2-hydroxy-3-thiazoline ring. As a result, the chromophore contained the CNCOH group at the 2-position of the imidazolinone moiety such that the conjugated pi-electron system of the chromophore was more extended than that of GFP but less extended than that of the Discosoma sp. red fluorescent protein (DsRed). Since a sulfur atom has potent nucleophilic character, the third 3-thiazoline ring is rapidly and completely cyclized. Furthermore, our structure reveals the presence of a pi-pi stacking interaction between His197 and the chromophore as well as a pi-cation interaction between Arg69 and the chromophore. These structural findings are sufficient to account for the orange emission, pH tolerance, and photostability of mKO.


    Organizational Affiliation

    Biometal Science Laboratory, RIKEN SPring-8 Center, 1-1-1, Kouto, Sayo, Hyogo 679-5148, Japan. kikuchi@spring8.or.jp



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Fluorescent proteinA, B, C, D223Lithophyllon concinnaMutation(s): 1 
Gene Names: mKO
UniProt
Find proteins for Q6I7B2 (Lithophyllon concinna)
Explore Q6I7B2 
Go to UniProtKB:  Q6I7B2
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
CFY
Query on CFY
A, B, C, DL-PEPTIDE LINKINGC23 H22 N4 O5 SPHE, CYS, TYR, GLY
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.232 
  • R-Value Work: 0.197 
  • R-Value Observed: 0.197 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 92.57α = 90
b = 72.11β = 102.72
c = 90.27γ = 90
Software Package:
Software NamePurpose
MOLREPphasing
CNSrefinement
ADSCdata collection
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2008-10-21
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2012-05-02
    Changes: Other, Source and taxonomy