4O8G

Structure of Infrared Fluorescent Protein 1.4


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.652 Å
  • R-Value Free: 0.211 
  • R-Value Work: 0.185 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Origins of fluorescence in evolved bacteriophytochromes.

Bhattacharya, S.Auldridge, M.E.Lehtivuori, H.Ihalainen, J.A.Forest, K.T.

(2014) J.Biol.Chem. 289: 32144-32152

  • DOI: 10.1074/jbc.M114.589739
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Use of fluorescent proteins to study in vivo processes in mammals requires near-infrared (NIR) biomarkers that exploit the ability of light in this range to penetrate tissue. Bacteriophytochromes (BphPs) are photoreceptors that couple absorbance of N ...

    Use of fluorescent proteins to study in vivo processes in mammals requires near-infrared (NIR) biomarkers that exploit the ability of light in this range to penetrate tissue. Bacteriophytochromes (BphPs) are photoreceptors that couple absorbance of NIR light to photoisomerization, protein conformational changes, and signal transduction. BphPs have been engineered to form NIR fluorophores, including IFP1.4, Wi-Phy, and the iRFP series, initially by replacement of Asp-207 by His. This position was suggestive because its main chain carbonyl is within hydrogen-bonding distance to pyrrole ring nitrogens of the biliverdin chromophore, thus potentially functioning as a crucial transient proton sink during photoconversion. To explain the origin of fluorescence in these phytofluors, we solved the crystal structures of IFP1.4 and a comparison non-fluorescent monomeric phytochrome DrCBDmon. Met-186 and Val-288 in IFP1.4 are responsible for the formation of a tightly packed hydrophobic hub around the biliverdin D ring. Met-186 is also largely responsible for the blue-shifted IFP1.4 excitation maximum relative to the parent BphP. The structure of IFP1.4 revealed decreased structural heterogeneity and a contraction of two surface regions as direct consequences of side chain substitutions. Unexpectedly, IFP1.4 with Asp-207 reinstalled (IFPrev) has a higher fluorescence quantum yield (∼9%) than most NIR phytofluors published to date. In agreement, fluorescence lifetime measurements confirm the exceptionally long excited state lifetimes, up to 815 ps, in IFP1.4 and IFPrev. Our research helps delineate the origin of fluorescence in engineered BphPs and will facilitate the wide-spread adoption of phytofluors as biomarkers.


    Organizational Affiliation

    From the Departments of Bacteriology, University of Wisconsin, Madison, Wisconsin 53706 and.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Bacteriophytochrome
A
329Deinococcus radiodurans (strain ATCC 13939 / DSM 20539 / JCM 16871 / LMG 4051 / NBRC 15346 / NCIMB 9279 / R1 / VKM B-1422)Mutation(s): 12 
Gene Names: bphP
EC: 2.7.13.3
Find proteins for Q9RZA4 (Deinococcus radiodurans (strain ATCC 13939 / DSM 20539 / JCM 16871 / LMG 4051 / NBRC 15346 / NCIMB 9279 / R1 / VKM B-1422))
Go to UniProtKB:  Q9RZA4
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
LBV
Query on LBV

Download SDF File 
Download CCD File 
A
3-[2-[(Z)-[3-(2-carboxyethyl)-5-[(Z)-(4-ethenyl-3-methyl-5-oxidanylidene-pyrrol-2-ylidene)methyl]-4-methyl-pyrrol-1-ium-2-ylidene]methyl]-5-[(Z)-[(3E)-3-ethylidene-4-methyl-5-oxidanylidene-pyrrolidin-2-ylidene]methyl]-4-methyl-1H-pyrrol-3-yl]propanoic acid
2(R),3(E)- PHYTOCHROMOBILIN
C33 H37 N4 O6
DKMLMZVDTGOEGU-ISEYCTJISA-O
 Ligand Interaction
LBW
Query on LBW

Download SDF File 
Download CCD File 
A
3-[2-[(Z)-[5-[(Z)-(4-ethenyl-3-methyl-5-oxidanylidene-pyrrol-2-ylidene)methyl]-3-(3-hydroxy-3-oxopropyl)-4-methyl-pyrrol-1-ium-2-ylidene]methyl]-5-[(Z)-[(3E,4R)-3-ethylidene-4-methyl-5-oxidanylidene-pyrrolidin-2-ylidene]methyl]-4-methyl-1H-pyrrol-3-yl]propanoic acid
C33 H37 N4 O6
DKMLMZVDTGOEGU-UAWLBFNISA-O
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.652 Å
  • R-Value Free: 0.211 
  • R-Value Work: 0.185 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 96.162α = 90.00
b = 53.228β = 90.60
c = 66.796γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data scaling
PHASERphasing
HKL-2000data reduction
REFMACrefinement
HKL-2000data collection

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-10-01
    Type: Initial release
  • Version 1.1: 2014-10-08
    Type: Database references
  • Version 1.2: 2014-12-03
    Type: Database references