6C7Z

Crystal structure of the Q108K:K40L:T51V:R58F mutant of human Cellular Retinol Binding Protein II in complex with synthetic Ligand Julolidine

• PDB DOI: https://doi.org/10.2210/pdb6C7Z/pdb

• Classification: TRANSPORT PROTEIN
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 2018-01-23 Released: 2018-04-25 
• Deposition Author(s): Nosrati, M., Geiger, J.H.
• 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: 1.42 Å
• R-Value Free: 0.256 
• R-Value Work: 0.222 
• R-Value Observed: 0.224 

Literature

A Genetically Encoded Ratiometric pH Probe: Wavelength Regulation-Inspired Design of pH Indicators.

Berbasova, T., Tahmasebi Nick, S., Nosrati, M., Nossoni, Z., Santos, E.M., Vasileiou, C., Geiger, J.H., Borhan, B.

(2018) Chembiochem 19: 1288-1295

• PubMed: 29645331 
• DOI: https://doi.org/10.1002/cbic.201800050
• Primary Citation of Related Structures:  
  6C7Z


• PubMed Abstract: 
  

  Mutants of human cellular retinol-binding protein II (hCRBPII) were engineered to bind a julolidine retinal analogue for the purpose of developing a ratiometric pH sensor. The design relied on the electrostatic influence of a titratable amino acid side chain, which affects the absorption and, thus, the emission of the protein/fluorophore complex. The ratio of emissions obtained at two excitation wavelengths that correspond to the absorption of the two forms of the protein/fluorophore complex, leads to a concentration-independent measure of pH.

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Organizational Affiliation: 

Department of Chemistry, Michigan State University, East Lansing, MI, 48824, USA.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly 2  

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

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 31.79 kDa 
• Atom Count: 2,456 
• Modelled Residue Count: 266 
• Deposited Residue Count: 266 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Retinol-binding protein 2	A, B	133	Homo sapiens	Mutation(s): 4  Gene Names: RBP2, CRBP2
UniProt & NIH Common Fund Data Resources
Find proteins for P50120 (Homo sapiens) Explore P50120  Go to UniProtKB:  P50120
PHAROS:  P50120 GTEx:  ENSG00000114113

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
JLO	D [auth A], F [auth B]	(2E,4E)-3-methyl-5-(2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinolin-9-yl)penta-2,4-dienal C18 H21 N O LJFLJZQWTCHPOI-MDVYSFJGSA-N
ACT	C [auth A], E [auth B]	ACETATE ION C2 H3 O2 QTBSBXVTEAMEQO-UHFFFAOYSA-M

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.42 Å
• R-Value Free: 0.256 
• R-Value Work: 0.222 
• R-Value Observed: 0.224 
• Space Group: P 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 29.787	α = 90.51
b = 35.947	β = 92.45
c = 64.089	γ = 113.31

Software Package:

Software Name	Purpose
PHENIX	refinement
HKL-3000	data reduction
HKL-3000	data scaling
PHENIX	phasing

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2018-04-25 
Deposition Author(s): Nosrati, M., Geiger, J.H.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)	United States	GM101353

Revision History  

• Version 1.0: 2018-04-25
  Type: Initial release
  
• Version 1.1: 2018-07-04
  Changes: Data collection, Database references
• Version 1.2: 2019-02-20
  Changes: Author supporting evidence, Data collection
• Version 1.3: 2022-03-23
  Changes: Author supporting evidence, Database references
• Version 1.4: 2023-10-04
  Changes: Data collection, Refinement description