2EZ7

Carbonic anhydrase activators. Activation of isozymes I, II, IV, VA, VII and XIV with L- and D-histidine and crystallographic analysis of their adducts with isoform II: engineering proton transfer processes within the active site of an enzyme


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.300 
  • R-Value Work: 0.249 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Carbonic Anhydrase Activators. Activation of Isozymes I, II, IV, VA, VII, and XIV with L- and D-Histidine and Crystallographic Analysis of Their Adducts with Isoform II: Engineering Proton-Transfer Processes within the Active Site of an Enzyme.

Temperini, C.Scozzafava, A.Vullo, D.Supuran, C.T.

(2006) Chemistry 12: 7057-7066

  • DOI: 10.1002/chem.200600159

  • PubMed Abstract: 
  • Activation of six human carbonic anhydrases (CA, EC 4.2.1.1), that is, hCA I, II, IV, VA, VII, and XIV, with l- and d-histidine was investigated through kinetics and by X-ray crystallography. l-His was a potent activator of isozymes I, VA, VII, and X ...

    Activation of six human carbonic anhydrases (CA, EC 4.2.1.1), that is, hCA I, II, IV, VA, VII, and XIV, with l- and d-histidine was investigated through kinetics and by X-ray crystallography. l-His was a potent activator of isozymes I, VA, VII, and XIV, and a weaker activator of hCA II and IV. d-His showed good hCA I, VA, and VII activation properties, being a moderate activator of hCA XIV and a weak activator of hCA II and IV. The structures as determined by X-ray crystallography of the hCA II-l-His/d-His adducts showed the activators to be anchored at the entrance of the active site, contributing to extended networks of hydrogen bonds with amino acid residues/water molecules present in the cavity, explaining their different potency and interaction patterns with various isozymes. The residues involved in l-His recognition were His64, Asn67, Gln92, whereas three water molecules connected the activator to the zinc-bound hydroxide. Only the imidazole moiety of l-His interacted with these amino acids. For the d-His adduct, the residues involved in recognition of the activator were Trp5, His64, and Pro201, whereas two water molecules connected the zinc-bound water to the activator. Only the COOH and NH(2) moieties of d-His participated in hydrogen bonds with these residues. This is the first study showing different binding modes of stereoisomeric activators within the hCA II active site, with consequences for overall proton-transfer processes (rate-determining for the catalytic cycle). The study also points out differences of activation efficiency between various isozymes with structurally related activators, convenient for designing alternative proton-transfer pathways, useful both for a better understanding of the catalytic mechanism and for obtaining pharmacologically useful derivatives, for example, for the management of Alzheimer's disease.


    Organizational Affiliation

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




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Carbonic anhydrase 2
A
260Homo sapiensGene Names: CA2
EC: 4.2.1.1
Find proteins for P00918 (Homo sapiens)
Go to Gene View: CA2
Go to UniProtKB:  P00918
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

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Download CCD File 
A
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
DHI
Query on DHI

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Download CCD File 
A
D-HISTIDINE
C6 H10 N3 O2
HNDVDQJCIGZPNO-RXMQYKEDSA-O
 Ligand Interaction
HG
Query on HG

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Download CCD File 
A
MERCURY (II) ION
Hg
BQPIGGFYSBELGY-UHFFFAOYSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
DHIKd: 43500 nM BINDINGMOAD
DHIKd: 43500 nM PDBBIND
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.300 
  • R-Value Work: 0.249 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 42.060α = 90.00
b = 41.430β = 104.40
c = 72.520γ = 90.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
CNSrefinement
AMoREphasing
MOSFLMdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-07-18
    Type: Initial release
  • Version 1.1: 2008-05-01
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance