2HKK

Carbonic anhydrase activators: Solution and X-ray crystallography for the interaction of andrenaline with various carbonic anhydrase isoforms

• PDB DOI:  https://doi.org/10.2210/pdb2HKK/pdb

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


• Deposited: 2006-07-05 Released: 2007-05-22 
• Deposition Author(s): Temperini, C., Innocenti, A., Vullo, D., Scozzafava, A., Supuran, C.T.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.233 
• R-Value Work: 0.186 
• R-Value Observed: 0.188 

Literature

Carbonic anhydrase activators: L-Adrenaline plugs the active site entrance of isozyme II, activating better isoforms I, IV, VA, VII, and XIV.

Temperini, C., Innocenti, A., Scozzafava, A., Mastrolorenzo, A., Supuran, C.T.

(2007) Bioorg Med Chem Lett 17: 628-635

• PubMed: 17127057 
• DOI: https://doi.org/10.1016/j.bmcl.2006.11.027
• Primary Citation of Related Structures:  
  2HKK


• PubMed Abstract: 
  

  The activation of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1) with L-adrenaline and histamine has been investigated by kinetic and X-ray crystallographic studies. L-Adrenaline behaves as a potent activator of isozyme CA I (activation constant of 90 nM), being a much weaker activator of isozyme CA II (activation constant of 96 microM). Isoforms CA IV, VA, VII, and XIV were activated by L-adrenaline with K(A)s in the range of 36-63 microM. The X-ray crystal structure of the CA II-L-adrenaline adduct revealed that the activator plugs the entrance of the active site cavity, obstructing it almost completely.

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Organizational Affiliation: 

Università degli Studi di Firenze, Laboratorio di Chimica Bioinorganica, Rm. 188, Via della Lastruccia 3, I-50019 Sesto Fiorentino (Firenze), Italy.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 29.74 kDa 
• Atom Count: 2,251 
• 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  Gene Names: CA2 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

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
HG	C [auth A]	MERCURY (II) ION Hg BQPIGGFYSBELGY-UHFFFAOYSA-N
ALE	D [auth A]	L-EPINEPHRINE C9 H13 N O3 UCTWMZQNUQWSLP-VIFPVBQESA-N
ZN	B [auth A]	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
ALE	Binding MOAD:  2HKK	Ka: 96 (M^-1) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.233 
• R-Value Work: 0.186 
• R-Value Observed: 0.188 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 42.1	α = 90
b = 41.43	β = 104.48
c = 72.2	γ = 90

Software Package:

Software Name	Purpose
AMoRE	phasing
REFMAC	refinement
MOSFLM	data reduction
SCALEPACK	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2007-05-22 
Deposition Author(s): Temperini, C., Innocenti, A., Vullo, D., Scozzafava, A., Supuran, C.T.

Revision History  

• Version 1.0: 2007-05-22
  Type: Initial release
  
• Version 1.1: 2007-10-16
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2013-03-20
  Changes: Non-polymer description
• Version 1.4: 2018-04-04
  Changes: Data collection
• Version 1.5: 2023-08-30
  Changes: Data collection, Database references, Derived calculations, Refinement description