Biological Assembly 1  

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

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 29.90 kDa 
• Atom Count: 2270 
• Modelled Residue Count: 258 
• Deposited Residue Count: 259 
• Unique protein chains: 1

1I8Z

CARBONIC ANHYDRASE II COMPLEXED WITH AL-6629 2H-THIENO[3,2-E]-1,2-THIAZINE-6-SULFONAMIDE, 2-(3-METHOXYPHENYL)-3-(4-MORPHOLINYL)-, 1,1-DIOXIDE

• PDB DOI: 10.2210/pdb1I8Z/pdb

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


• Deposited: 2001-03-16 Released: 2001-03-28 
• Deposition Author(s): Kim, C.-Y., Chang, J.S., Liao, J., May, J.A., Christianson, D.W.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.93 Å
• R-Value Free: 0.293 
• R-Value Work: 0.223 

Literature

Structural aspects of isozyme selectivity in the binding of inhibitors to carbonic anhydrases II and IV.

Kim, C.Y., Whittington, D.A., Chang, J.S., Liao, J., May, J.A., Christianson, D.W.

(2002) J Med Chem 45: 888-893

• PubMed: 11831900 
• DOI: 10.1021/jm010163d
• Primary Citation of Related Structures:  
  1I8Z, 1I90, 1I91


• PubMed Abstract: 
  

Carbonic anhydrase inhibitors are effective in lowering intraocular pressure, the primary indication of glaucoma. Human carbonic anhydrase II, and possibly carbonic anhydrase IV (CAII and CAIV, respectively), help regulate fluid secretion into the anterior chamber of the eye. Because inhibitors currently formulated as drugs to treat glaucoma were designed to target CAII, an understanding of the structural basis of CAII-CAIV discrimination by inhibitors would be useful for probing the role of each isozyme in the etiology of the disease. Here, we report the X-ray crystal structures of three novel thieno[3,2-e]-1,2-thiazine-6-sulfonamides complexed with CAII and the computationally predicted structures of the same compounds complexed with CAIV. All three compounds bind with similar affinity to CAII, but they bind with up to 100-fold lower affinities to CAIV. Comparisons of experimentally determined structures of CAII-inhibitor complexes and computationally predicted structures of CAIV-inhibitor complexes allow us to rationalize these affinity trends and outline molecular features that may contribute to high-affinity inhibitor binding to CAIV. This study demonstrates how experimental structure determination methods and computational structure prediction methods can be used together to answer questions that cannot be answered by either method alone.

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Organizational Affiliation: 

Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104-6323, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
CARBONIC ANHYDRASE II	A	259	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

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
INL	D [auth A]	6-[N-(3-METHOXY-PHENYL)-3-(MORPHOLIN-4-YLMETHYL)-2H-THIENO[3,2-E]-1,2-THIAZINE-1,1,-DIOXIDE]-SULFONAMIDE C18 H21 N3 O6 S3 XSUAVPPTKHUTDX-UHFFFAOYSA-N
HG	C [auth A]	MERCURY (II) ION Hg BQPIGGFYSBELGY-UHFFFAOYSA-N
ZN	B [auth A]	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
INL	BindingDB:  1I8Z	Ki: 0.15 (nM) from 1 assay(s)
		IC50: min: 1.27, max: 1.3 (nM) from 2 assay(s)
	Binding MOAD:  1I8Z	IC50: 1.27 (nM) from 1 assay(s)
	PDBBind:  1I8Z	IC50: 1.27 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.93 Å
• R-Value Free: 0.293 
• R-Value Work: 0.223 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 43	α = 90
b = 42.2	β = 104.9
c = 74	γ = 90

Software Package:

Software Name	Purpose
X-PLOR	model building
X-PLOR	refinement
DENZO	data reduction
SCALEPACK	data scaling
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2001-03-16 
• Released Date: 2001-03-28 
Deposition Author(s): Kim, C.-Y., Chang, J.S., Liao, J., May, J.A., Christianson, D.W.

Revision History  

• Version 1.0: 2001-03-28
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2018-04-04
  Changes: Data collection