6S03

Carbonic Anhydrase CAIX mimic in complex with inhibitor I39LT379


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.38 Å
  • R-Value Free: 0.196 
  • R-Value Work: 0.171 
  • R-Value Observed: 0.172 

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 


This is version 1.3 of the entry. See complete history


Literature

Identification of Novel Carbonic Anhydrase IX Inhibitors Using High-Throughput Screening of Pooled Compound Libraries by DNA-Linked Inhibitor Antibody Assay (DIANA).

Tykvart, J.Navratil, V.Kugler, M.Sacha, P.Schimer, J.Hlavackova, A.Tenora, L.Zemanova, J.Dejmek, M.Kral, V.Potacek, M.Majer, P.Jahn, U.Brynda, J.Rezacova, P.Konvalinka, J.

(2020) SLAS Discov 25: 1026-1037

  • DOI: https://doi.org/10.1177/2472555220918836
  • Primary Citation of Related Structures:  
    6RZX, 6S03

  • PubMed Abstract: 

    The DNA-linked inhibitor antibody assay (DIANA) has been recently validated for ultrasensitive enzyme detection and for quantitative evaluation of enzyme inhibitor potency. Here we present its adaptation for high-throughput screening of human carbonic anhydrase IX (CAIX), a promising drug and diagnostic target. We tested DIANA's performance by screening a unique compound collection of 2816 compounds consisting of lead-like small molecules synthesized at the Institute of Organic Chemistry and Biochemistry (IOCB) Prague ("IOCB library"). Additionally, to test the robustness of the assay and its potential for upscaling, we screened a pooled version of the IOCB library. The results from the pooled screening were in agreement with the initial nonpooled screen with no lost hits and no false positives, which shows DIANA's potential to screen more than 100,000 compounds per day.All DIANA screens showed a high signal-to-noise ratio with a Z' factor of >0.89. The DIANA screen identified 13 compounds with K i values equal to or better than 10 µM. All retested hits were active also in an orthogonal enzymatic assay showing zero false positives. However, further biophysical validation of identified hits revealed that the inhibition activity of several hits was caused by a single highly potent CAIX inhibitor, being present as a minor impurity. This finding eventually led us to the identification of three novel CAIX inhibitors from the screen. We confirmed the validity of these compounds by elucidating their mode of binding into the CAIX active site by x-ray crystallography.


  • Organizational Affiliation

    Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague, Czech Republic.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Carbonic anhydrase 2260Homo sapiensMutation(s): 0 
Gene Names: CA2
EC: 4.2.1.1
UniProt & NIH Common Fund Data Resources
Find proteins for P00918 (Homo sapiens)
Explore P00918 
Go to UniProtKB:  P00918
PHAROS:  P00918
GTEx:  ENSG00000104267 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP00918
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
KPW (Subject of Investigation/LOI)
Query on KPW

Download Ideal Coordinates CCD File 
C [auth A]4-[[4-[5,5-dimethyl-2-(6-methylpyridin-2-yl)-4,6-dihydropyrrolo[1,2-b]pyrazol-3-yl]pyridin-2-yl]amino]benzenesulfonamide
C25 H26 N6 O2 S
MOQLTEFWRJQFEZ-UHFFFAOYSA-N
ZN
Query on ZN

Download Ideal Coordinates CCD File 
B [auth A]ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
Binding Affinity Annotations 
IDSourceBinding Affinity
KPW Binding MOAD:  6S03 Ki: 17 (nM) from 1 assay(s)
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.38 Å
  • R-Value Free: 0.196 
  • R-Value Work: 0.171 
  • R-Value Observed: 0.172 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 42.06α = 90
b = 41.52β = 103.8
c = 72.19γ = 90
Software Package:
Software NamePurpose
XDSdata reduction
XSCALEdata scaling
REFMACrefinement
PDB_EXTRACTdata extraction
FFTphasing

Structure Validation

View Full Validation Report



Ligand Structure Quality Assessment 


Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Ministry of Education (Czech Republic)Czech RepublicLO1304

Revision History  (Full details and data files)

  • Version 1.0: 2020-06-03
    Type: Initial release
  • Version 1.1: 2020-06-10
    Changes: Database references
  • Version 1.2: 2020-09-30
    Changes: Database references
  • Version 1.3: 2024-01-24
    Changes: Data collection, Database references, Refinement description