Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report

Global Symmetry: Dihedral - D2  (3D View)
Global Stoichiometry: Homo 4-mer - A4 

Biological assembly 1 assigned by authors.

Biological Assembly 2  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report

Global Symmetry: Dihedral - D2  (3D View)
Global Stoichiometry: Homo 4-mer - A4 

Biological assembly 2 assigned by authors.

Macromolecule Content

• Total Structure Weight: 232.05 kDa 
• Atom Count: 13844 
• Modelled Residue Count: 1739 
• Deposited Residue Count: 2040 
• Unique protein chains: 1

6NQR

Crystal structure of fast switching M159T mutant of fluorescent protein Dronpa (Dronpa2)- Y63(3-NO2Y)

• PDB DOI: 10.2210/pdb6NQR/pdb

• Classification: FLUORESCENT PROTEIN
• Organism(s): Echinophyllia sp. SC22
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): Yes 


• Deposited: 2019-01-21 Released: 2019-06-12 
• Deposition Author(s): Lin, C.-Y., Romei, M.G., Mathews, I.I., Boxer, S.G.
• Funding Organization(s): National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.90 Å
• R-Value Free: 0.283 
• R-Value Work: 0.216 
• R-Value Observed: 0.220 

Literature

Electrostatic control of photoisomerization pathways in proteins.

Romei, M.G., Lin, C.Y., Mathews, I.I., Boxer, S.G.

(2020) Science 367: 76-79

• PubMed: 31896714 
• DOI: 10.1126/science.aax1898
• Primary Citation of Related Structures:  
  6NQJ, 6NQK, 6NQL, 6NQN, 6NQO, 6NQP, 6NQQ, 6NQR, 6NQS, 6NQV


• PubMed Abstract: 
  

Rotation around a specific bond after photoexcitation is central to vision and emerging opportunities in optogenetics, super-resolution microscopy, and photoactive molecular devices. Competing roles for steric and electrostatic effects that govern bond-specific photoisomerization have been widely discussed, the latter originating from chromophore charge transfer upon excitation. We systematically altered the electrostatic properties of the green fluorescent protein chromophore in a photoswitchable variant, Dronpa2, using amber suppression to introduce electron-donating and electron-withdrawing groups to the phenolate ring. Through analysis of the absorption (color), fluorescence quantum yield, and energy barriers to ground- and excited-state isomerization, we evaluate the contributions of sterics and electrostatics quantitatively and demonstrate how electrostatic effects bias the pathway of chromophore photoisomerization, leading to a generalized framework to guide protein design.

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Organizational Affiliation: 

Department of Chemistry, Stanford University, Stanford, CA 94305, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Fluorescent protein Dronpa	A, B, C, D, E, F, G, H	255	Echinophyllia sp. SC22	Mutation(s): 3  Gene Names: Dronpa
UniProt
Find proteins for Q5TLG6 (Echinophyllia sp. SC22) Explore Q5TLG6  Go to UniProtKB:  Q5TLG6

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.90 Å
• R-Value Free: 0.283 
• R-Value Work: 0.216 
• R-Value Observed: 0.220 
• Space Group: P 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 71.61	α = 89.96
b = 79.43	β = 92.53
c = 85.93	γ = 94.76

Software Package:

Software Name	Purpose
PHENIX	refinement
XDS	data reduction
XDS	data scaling
PHENIX	phasing

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2019-01-21 
• Released Date: 2019-06-12 
Deposition Author(s): Lin, C.-Y., Romei, M.G., Mathews, I.I., Boxer, S.G.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)	United States	27738
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)	United States	118044

Revision History  

• Version 1.0: 2019-06-12
  Type: Initial release
  
• Version 1.1: 2019-12-25
  Changes: Database references
• Version 1.2: 2020-01-01
  Changes: Author supporting evidence
• Version 1.3: 2020-01-15
  Changes: Database references
• Version 1.4: 2020-02-05
  Changes: Database references