PDBsum entry 1cao

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Lyase(oxo-acid) PDB id
Protein chain
260 a.a. *
Waters ×230
* Residue conservation analysis
PDB id:
Name: Lyase(oxo-acid)
Title: Crystallographic studies of the binding of protonated and unprotonated inhibitors to carbonic anhydrase using hydrogen sulphide and nitrate anions
Structure: Carbonic anhydrase ii. Chain: a. Engineered: yes
Source: Homo sapiens. Human. Organism_taxid: 9606
1.90Å     R-factor:   0.146    
Authors: S.Mangani,K.Hakansson
Key ref: S.Mangani and K.Håkansson (1992). Crystallographic studies of the binding of protonated and unprotonated inhibitors to carbonic anhydrase using hydrogen sulphide and nitrate anions. Eur J Biochem, 210, 867-871. PubMed id: 1336460
02-Jul-92     Release date:   31-Jan-94    
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Protein chain
Pfam   ArchSchema ?
P00918  (CAH2_HUMAN) -  Carbonic anhydrase 2
260 a.a.
259 a.a.
Key:    PfamA domain  Secondary structure  CATH domain

 Gene Ontology (GO) functional annotation 
  GO annot!
  Cellular component     extracellular space   11 terms 
  Biological process     angiotensin-mediated signaling pathway   22 terms 
  Biochemical function     protein binding     5 terms  


Eur J Biochem 210:867-871 (1992)
PubMed id: 1336460  
Crystallographic studies of the binding of protonated and unprotonated inhibitors to carbonic anhydrase using hydrogen sulphide and nitrate anions.
S.Mangani, K.Håkansson.
The structures of human carbonic-anhydrase-II complexes with the anionic inhibitors hydrogen sulphide (HS-) and nitrate (NO3-) have been determined by X-ray diffraction at 0.19-nm resolution from crystals soaked at pH 7.8 and 6.0, respectively. The modes of binding of these two anions differ markedly from each other. The strong inhibitor HS- replaces the native zinc-bound water/hydroxide (Wat263) leaving the tetrahedral metal geometry unaltered and acts as a hydrogen-bonding donor towards Thr199 gamma. The weak NO3- inhibitor does not displace Wat263 from the metal coordination but occupies a fifth binding site changing the zinc coordination polyhedron into a slightly distorted trigonal bipyramid. The interaction of NO3- with the metal is weak; the nearest of its oxygen atoms being at a distance of 0.28 nm from the zinc ion. The binding of nitrate to the enzyme is completed by a hydrogen bond to the metal coordinated Wat263 and a second one to a water molecule of the active-site cavity. The structures of the two complexes help to rationalize the binding of anionic inhibitors to carbonic anhydrase and the binding mode displayed by NO39 may be relevant to the catalytic mechanism.

Literature references that cite this PDB file's key reference

  PubMed id Reference
18335973 V.M.Krishnamurthy, G.K.Kaufman, A.R.Urbach, I.Gitlin, K.L.Gudiksen, D.B.Weibel, and G.M.Whitesides (2008).
Carbonic anhydrase as a model for biophysical and physical-organic studies of proteins and protein-ligand binding.
  Chem Rev, 108, 946.  
17822366 K.Umemura, and H.Kimura (2007).
Hydrogen sulfide enhances reducing activity in neurons: neurotrophic role of H2S in the brain?
  Antioxid Redox Signal, 9, 2035-2041.  
13678538 R.Wang (2003).
The gasotransmitter role of hydrogen sulfide.
  Antioxid Redox Signal, 5, 493-501.  
11015219 A.Guerri, F.Briganti, A.Scozzafava, C.T.Supuran, and S.Mangani (2000).
Mechanism of cyanamide hydration catalyzed by carbonic anhydrase II suggested by cryogenic X-ray diffraction.
  Biochemistry, 39, 12391-12397.
PDB code: 1f2w
  10515911 K.S.Smith, and J.G.Ferry (1999).
A plant-type (beta-class) carbonic anhydrase in the thermophilic methanoarchaeon Methanobacterium thermoautotrophicum.
  J Bacteriol, 181, 6247-6253.  
9061790 C.T.Supuran, C.W.Conroy, and T.H.Maren (1997).
Is cyanate a carbonic anhydrase substrate?
  Proteins, 27, 272-278.  
9265618 F.Briganti, S.Mangani, P.Orioli, A.Scozzafava, G.Vernaglione, and C.T.Supuran (1997).
Carbonic anhydrase activators: X-ray crystallographic and spectroscopic investigations for the interaction of isozymes I and II with histamine.
  Biochemistry, 36, 10384-10392.
PDB code: 1avn
9336012 S.Lindskog (1997).
Structure and mechanism of carbonic anhydrase.
  Pharmacol Ther, 74, 1.  
8306976 A.Liljas, K.Håkansson, B.H.Jonsson, and Y.Xue (1994).
Inhibition and catalysis of carbonic anhydrase. Recent crystallographic analyses.
  Eur J Biochem, 219, 1.  
  7920263 L.C.Pedersen, V.C.Yee, P.D.Bishop, I.Le Trong, D.C.Teller, and R.E.Stenkamp (1994).
Transglutaminase factor XIII uses proteinase-like catalytic triad to crosslink macromolecules.
  Protein Sci, 3, 1131-1135.  
7913750 V.C.Yee, L.C.Pedersen, I.Le Trong, P.D.Bishop, R.E.Stenkamp, and D.C.Teller (1994).
Three-dimensional structure of a transglutaminase: human blood coagulation factor XIII.
  Proc Natl Acad Sci U S A, 91, 7296-7300.
PDB code: 1ggt
8477723 S.K.Nair, and D.W.Christianson (1993).
Crystallographic studies of azide binding to human carbonic anhydrase II.
  Eur J Biochem, 213, 507-515.  
The most recent references are shown first. Citation data come partly from CiteXplore and partly from an automated harvesting procedure. Note that this is likely to be only a partial list as not all journals are covered by either method. However, we are continually building up the citation data so more and more references will be included with time. Where a reference describes a PDB structure, the PDB code is shown on the right.