2Q1B

Carbonic Anhydrase II in Complex with Saccharin

• PDB DOI: https://doi.org/10.2210/pdb2Q1B/pdb

• Classification: LYASE
• Organism(s): Homo sapiens
• Mutation(s): No 


• Deposited: 2007-05-24 Released: 2007-09-04 
• Deposition Author(s): Klebe, G., Heine, A., Koehler, K.

---

Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.70 Å
• R-Value Free: 
  0.216 (Depositor), 0.170 (DCC) 
• R-Value Work: 
  0.146 (Depositor), 0.160 (DCC) 

Starting Model: experimental

Literature

Saccharin Inhibits Carbonic Anhydrases: Possible Explanation for its Unpleasant Metallic Aftertaste.

Kohler, K., Hillebrecht, A., Schulze Wischeler, J., Innocenti, A., Heine, A., Supuran, C.T., Klebe, G.

(2007) Angew Chem Int Ed Engl 46: 7697-7699

• PubMed: 17705204 
• DOI: https://doi.org/10.1002/anie.200701189
• Primary Citation of Related Structures:  
  2Q1B, 2Q38

---

Organizational Affiliation: 

Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35032 Marburg, Germany.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 29.93 kDa 
• Atom Count: 2,414 
• Modelled Residue Count: 256 
• Deposited Residue Count: 260 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Carbonic anhydrase 2	A	260	Homo sapiens	Mutation(s): 0  EC: 4.2.1.1 (PDB Primary Data), 4.2.1.69 (UniProt)
UniProt & NIH Common Fund Data Resources
Find proteins for P00918 (Homo sapiens) Explore P00918  Go to UniProtKB:  P00918
PHAROS:  P00918 GTEx:  ENSG00000104267

Small Molecules

Ligands 4 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
HG	D [auth A]	MERCURY (II) ION Hg BQPIGGFYSBELGY-UHFFFAOYSA-N
LSA	F [auth A]	1,2-BENZISOTHIAZOL-3(2H)-ONE 1,1-DIOXIDE C7 H5 N O3 S CVHZOJJKTDOEJC-UHFFFAOYSA-N
BEZ	E [auth A]	BENZOIC ACID C7 H6 O2 WPYMKLBDIGXBTP-UHFFFAOYSA-N
ZN	B [auth A], C [auth A]	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.70 Å
• R-Value Free:  0.216 (Depositor), 0.170 (DCC) 
• R-Value Work:  0.146 (Depositor), 0.160 (DCC) 

Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 42.22	α = 90
b = 41.61	β = 104.44
c = 72.16	γ = 90

Software Package:

Software Name	Purpose
SHELX	model building
SHELXL-97	refinement
CrystalClear	data collection
HKL-2000	data reduction
HKL-2000	data scaling
CNS	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2007-09-04 
Deposition Author(s): Klebe, G., Heine, A., Koehler, K.

Revision History  

• Version 1.0: 2007-09-04
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Version format compliance
• Version 1.2: 2023-08-30
  Changes: Data collection, Database references, Derived calculations, Refinement description