8U22 | pdb_00008u22

A Highly Stable Variant of Corynactis Californica Green Fluorescent Protein, ccGFP 7

• PDB DOI: https://doi.org/10.2210/pdb8U22/pdb

• Classification: FLUORESCENT PROTEIN
• Organism(s): Corynactis californica
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2023-09-05 Released: 2024-01-31 
• Deposition Author(s): Hung, L.-W., Terwilliger, T.C., Waldo, G., Nguyen, H.B.
• Funding Organization(s): National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)

---

Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Free: 
  0.210 (Depositor), 0.210 (DCC) 
• R-Value Work: 
  0.180 (Depositor), 0.182 (DCC) 
• R-Value Observed: 
  0.183 (Depositor) 

Starting Model: experimental

Literature

Engineering highly stable variants of Corynactis californica green fluorescent proteins.

Hung, L.W., Terwilliger, T.C., Waldo, G.S., Nguyen, H.B.

(2024) Protein Sci 33: e4886-e4886

• PubMed: 38151801 
• DOI: https://doi.org/10.1002/pro.4886
• Primary Citation Related Structures: 
  8U20, 8U21, 8U22, 8U23, 8U24


• PubMed Abstract: 
  

  Fluorescent proteins (FPs) are versatile biomarkers that facilitate effective detection and tracking of macromolecules of interest in real time. Engineered FPs such as superfolder green fluorescent protein (sfGFP) and superfolder Cherry (sfCherry) have exceptional refolding capability capable of delivering fluorescent readout in harsh environments where most proteins lose their native functions. Our recent work on the development of a split FP from a species of strawberry anemone, Corynactis californica, delivered pairs of fragments with up to threefold faster complementation than split GFP. We present the biophysical, biochemical, and structural characteristics of five full-length variants derived from these split C. californica GFP (ccGFP). These ccGFP variants are more tolerant under chemical denaturation with up to 8 kcal/mol lower unfolding free energy than that of the sfGFP. It is likely that some of these ccGFP variants could be suitable as biomarkers under more adverse environments where sfGFP fails to survive. A structural analysis suggests explanations of the variations in stabilities among the ccGFP variants.

---

Organizational Affiliation: 
• Bioscience Division, MS M888, Los Alamos National Laboratory, Los Alamos, New Mexico, USA.
New Mexico Consortium, Los Alamos, New Mexico, USA.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 25.04 kDa 
• Atom Count: 1,993 
• Modeled Residue Count: 212 
• Deposited Residue Count: 219 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Green Fluorescent Protein Variant #7, ccGFP 7	A	219	Corynactis californica	Mutation(s): 0
UniProt
Find proteins for Q1ALD4 (Corynactis californica) Explore Q1ALD4  Go to UniProtKB:  Q1ALD4

Small Molecules

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
C12	A	L-PEPTIDE LINKING	C15 H18 N3 O5		THR, TYR, GLY

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Free:  0.210 (Depositor), 0.210 (DCC) 
• R-Value Work:  0.180 (Depositor), 0.182 (DCC) 
• R-Value Observed: 0.183 (Depositor) 

Space Group: P 4₃ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 54.582	α = 90
b = 54.582	β = 90
c = 169.303	γ = 90

Software Package:

Software Name	Purpose
PHENIX	refinement
HKL-2000	data scaling
HKL-2000	data reduction
PHASER	phasing

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2024-01-31 
Deposition Author(s): Hung, L.-W., Terwilliger, T.C., Waldo, G., Nguyen, H.B.

---

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

Revision History  

• Version 1.0: 2024-01-31
  Type: Initial release
  
• Version 1.1: 2024-02-07
  Changes: Database references
• Version 2.0: 2024-07-10
  Changes: Data collection, Derived calculations, Non-polymer description, Structure summary
• Version 2.1: 2024-10-23
  Changes: Structure summary
• Version 3.0: 2026-03-18
  Changes: Polymer sequence