Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report | Ligand Interaction

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

Biological assembly 1 generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 30.33 kDa 
• Atom Count: 2317 
• Modelled Residue Count: 258 
• Deposited Residue Count: 262 
• Unique protein chains: 1

4XE1

Human carbonic anhydrase II in complex with 6-SULFAMOYL-SACCHARIN

• PDB DOI: 10.2210/pdb4XE1/pdb

• Classification: LYASE
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2014-12-21 Released: 2015-03-18 
• Deposition Author(s): Alterio, V., De Simone, G.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Free: 0.214 
• R-Value Work: 0.168 

Literature

X-ray crystallographic and kinetic investigations of 6-sulfamoyl-saccharin as a carbonic anhydrase inhibitor.

Alterio, V., Tanc, M., Ivanova, J., Zalubovskis, R., Vozny, I., Monti, S.M., Di Fiore, A., De Simone, G., Supuran, C.T.

(2015) Org Biomol Chem 13: 4064-4069

• PubMed: 25733161 
• DOI: 10.1039/c4ob02648a
• Primary Citation of Related Structures:  
  4XE1


• PubMed Abstract: 
  

6-Sulfamoyl-saccharin was investigated as an inhibitor of 11 α-carbonic anhydrase (CA, EC 4.2.1.1) isoforms of human (h) origin, hCA I-XIV, and X-ray crystallographic data were obtained for its adduct with hCA II, the physiologically dominant isoform. This compound possesses two potential zinc-binding groups, the primary sulfamoyl one and the secondary, acylatedsulfonamide. Saccharin itself binds to the Zn(II) ion from the CA active site coordinating with this last group, in deprotonated (SO2N(-)CO) form. Here we explain why 6-sulfamoyl-saccharin, unlike saccharin, binds to the metal ion from the hCA II active site by its primary sulfonamide moiety and not the secondary one as saccharin itself. Our study is useful for shedding new light to the structure-based drug design of isoform-selective CA inhibitors of the sulfonamide type.

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Organizational Affiliation: 

Istituto di Biostrutture e Bioimmagini-CNR, via Mezzocannone 16, 80134 Naples, Italy.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Carbonic anhydrase 2	A	262	Homo sapiens	Mutation(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

Small Molecules

Ligands 4 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
HGB	E [auth A]	4-(HYDROXYMERCURY)BENZOIC ACID C7 H6 Hg O3 WMHRYLDWLOGHSG-UHFFFAOYSA-M
IL5	F [auth A]	3-oxo-2,3-dihydro-1,2-benzothiazole-6-sulfonamide 1,1-dioxide C7 H6 N2 O5 S2 CRSHTYPFKXPVRE-UHFFFAOYSA-N
GOL	C [auth A], D [auth A]	GLYCEROL C3 H8 O3 PEDCQBHIVMGVHV-UHFFFAOYSA-N
ZN	B [auth A]	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
IL5	Binding MOAD:  4XE1	Ki: 77.3 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Free: 0.214 
• R-Value Work: 0.168 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 42.212	α = 90
b = 41.68	β = 104.33
c = 71.731	γ = 90

Software Package:

Software Name	Purpose
HKL-2000	data reduction
CNS	refinement
PDB_EXTRACT	data extraction
SCALEPACK	data scaling
O	model building

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2014-12-21 
• Released Date: 2015-03-18 
Deposition Author(s): Alterio, V., De Simone, G.

Revision History  

• Version 1.0: 2015-03-18
  Type: Initial release
  
• Version 1.1: 2015-03-25
  Changes: Database references