Crystal structure of human carbonic anhydrase II in complex with the inhibitor famotidine

Experimental Data Snapshot

  • Resolution: 1.01 Å
  • R-Value Free: 0.151 
  • R-Value Work: 0.127 
  • R-Value Observed: 0.128 

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Famotidine, an Antiulcer Agent, Strongly InhibitsHelicobacter pyloriand Human Carbonic Anhydrases.

Angeli, A.Ferraroni, M.Supuran, C.T.

(2018) ACS Med Chem Lett 9: 1035-1038

  • DOI: https://doi.org/10.1021/acsmedchemlett.8b00334
  • Primary Citation of Related Structures:  
    6G3Q, 6G3V

  • PubMed Abstract: 

    Famotidine, an antiulcer drug incorporating a sulfamide motif, was investigated as carbonic anhydrase inhibitor (CAI). It acts as a nanomolar inhibitor of several human (hCA II, VI, VII and XII) and Helicobacter pylori CAs. The high resolution X-ray structures of famotidine bound to hCA I and II revealed interesting aspects related to its CA inhibition mechanism, offering the possibility to develop antibacterials with a novel mechanism of action.

  • Organizational Affiliation

    University of Florence, NEUROFARBA Dept., Sezione di Scienze Farmaceutiche, Via Ugo Schiff 6, 50019 Sesto Fiorentino, Florence, Italy.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Carbonic anhydrase 2260Homo sapiensMutation(s): 0 
UniProt & NIH Common Fund Data Resources
Find proteins for P00918 (Homo sapiens)
Explore P00918 
Go to UniProtKB:  P00918
GTEx:  ENSG00000104267 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP00918
Sequence Annotations
  • Reference Sequence
Small Molecules
Binding Affinity Annotations 
IDSourceBinding Affinity
FO9 Binding MOAD:  6G3Q Ki: 57.9 (nM) from 1 assay(s)
Experimental Data & Validation

Experimental Data

  • Resolution: 1.01 Å
  • R-Value Free: 0.151 
  • R-Value Work: 0.127 
  • R-Value Observed: 0.128 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 42.316α = 90
b = 41.439β = 104.34
c = 72.112γ = 90
Software Package:
Software NamePurpose
XDSdata reduction
XSCALEdata scaling
PDB_EXTRACTdata extraction

Structure Validation

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Ligand Structure Quality Assessment 

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2018-11-28
    Type: Initial release
  • Version 1.1: 2024-01-17
    Changes: Data collection, Database references, Refinement description