4QX4

Human Aldose Reductase complexed with a ligand with a new scaffold at 1.26 A

• PDB DOI: https://doi.org/10.2210/pdb4QX4/pdb

• Classification: oxidoreductase/oxidoreductase inhibitor
• Organism(s): Homo sapiens
• Expression System: Escherichia coli BL21
• Mutation(s): Yes 


• Deposited: 2014-07-18 Released: 2015-04-01 
• Deposition Author(s): Rechlin, C., Heine, A., Klebe, G.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.26 Å
• R-Value Free: 0.153 
• R-Value Work: 0.133 
• R-Value Observed: 0.134 

Literature

Identification of novel aldose reductase inhibitors based on carboxymethylated mercaptotriazinoindole scaffold.

Stefek, M., Soltesova Prnova, M., Majekova, M., Rechlin, C., Heine, A., Klebe, G.

(2015) J Med Chem 58: 2649-2657

• PubMed: 25695864 
• DOI: https://doi.org/10.1021/jm5015814
• Primary Citation of Related Structures:  
  4QX4


• PubMed Abstract: 
  

  Fifteen compounds, sharing an indole-1-acetic acid moiety as a common fragment, were selected from commercial databases for testing aldose reductase inhibition. 3-Mercapto-5H-1,2,4-triazino[5,6-b]indole-5-acetic acid (13) was the most promising inhibitor, with an IC50 in the submicromolar range and high selectivity, relative to aldehyde reductase. The crystal structure of aldose reductase complexed with 13 revealed an interaction pattern explaining its high affinity. Physicochemical parameters underline the excellent "leadlikeness" of 13 as a promising candidate for further structure optimizations.

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Organizational Affiliation: 

†Institute of Experimental Pharmacology and Toxicology, Slovak Academy of Sciences, Dubravska Cesta 9, 841 04 Bratislava, Slovakia.

Biological Assembly 1  

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

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

Macromolecule Content

• Total Structure Weight: 37.16 kDa 
• Atom Count: 2,991 
• Modelled Residue Count: 316 
• Deposited Residue Count: 316 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Aldose reductase	A	316	Homo sapiens	Mutation(s): 1  Gene Names: AKR1B1, ALDR1 EC: 1.1.1.21
UniProt & NIH Common Fund Data Resources
Find proteins for P15121 (Homo sapiens) Explore P15121  Go to UniProtKB:  P15121
PHAROS:  P15121 GTEx:  ENSG00000085662

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
NAP	B [auth A]	NADP NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE C21 H28 N7 O17 P3 XJLXINKUBYWONI-NNYOXOHSSA-N
3E2	C [auth A], D [auth A]	(3-thioxo-2,3-dihydro-5H-[1,2,4]triazino[5,6-b]indol-5-yl)acetic acid C11 H8 N4 O2 S LCMDWJXBUZDEKA-UHFFFAOYSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
3E2	Binding MOAD:  4QX4	IC50: 97 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.26 Å
• R-Value Free: 0.153 
• R-Value Work: 0.133 
• R-Value Observed: 0.134 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 49.43	α = 90
b = 66.932	β = 91.92
c = 47.411	γ = 90

Software Package:

Software Name	Purpose
MAR345dtb	data collection
PHASER	phasing
PHENIX	refinement
HKL-2000	data reduction
HKL-2000	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2015-04-01 
Deposition Author(s): Rechlin, C., Heine, A., Klebe, G.

Revision History  

• Version 1.0: 2015-04-01
  Type: Initial release
  
• Version 1.1: 2015-05-13
  Changes: Database references
• Version 1.2: 2023-09-20
  Changes: Data collection, Database references, Derived calculations, Refinement description