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3ca2

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Revision as of 07:13, 29 November 2017

CRYSTALLOGRAPHIC STUDIES OF INHIBITOR BINDING SITES IN HUMAN CARBONIC ANHYDRASE II. A PENTACOORDINATED BINDING OF THE SCN-ION TO THE ZINC AT HIGH P*H

Structural highlights

3ca2 is a 1 chain structure with sequence from Human. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	, ,
Activity:	Carbonate dehydratase, with EC number 4.2.1.1
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Disease

[CAH2_HUMAN] Defects in CA2 are the cause of osteopetrosis autosomal recessive type 3 (OPTB3) [MIM:259730]; also known as osteopetrosis with renal tubular acidosis, carbonic anhydrase II deficiency syndrome, Guibaud-Vainsel syndrome or marble brain disease. Osteopetrosis is a rare genetic disease characterized by abnormally dense bone, due to defective resorption of immature bone. The disorder occurs in two forms: a severe autosomal recessive form occurring in utero, infancy, or childhood, and a benign autosomal dominant form occurring in adolescence or adulthood. Autosomal recessive osteopetrosis is usually associated with normal or elevated amount of non-functional osteoclasts. OPTB3 is associated with renal tubular acidosis, cerebral calcification (marble brain disease) and in some cases with mental retardation.^[1] ^[2] ^[3] ^[4] ^[5]

Function

[CAH2_HUMAN] Essential for bone resorption and osteoclast differentiation (By similarity). Reversible hydration of carbon dioxide. Can hydrate cyanamide to urea. Involved in the regulation of fluid secretion into the anterior chamber of the eye.^[6] ^[7]

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

The binding of four inhibitors--mercuric ion, 3-acetoxymercuri-4-aminobenzenesulfonamide (AMS), acetazolamide (Diamox), and thiocyanate ion--to human carbonic anhydrase II (HCA II) has been studied with X-ray crystallography. The binding of mercury to HCA II at pH 7.0 has been investigated at 3.1 A resolution. Mercuric ions are observed at both nitrogens in the His-64 ring. One of these sites is pointing toward the zinc ion. The only other binding site for mercury is at Cys-206. The binding of the two sulfonamide inhibitors AMS and Diamox, has been reinvestigated at 2.0 and 3.0 A, respectively. Only the nitrogen of the sulfonamide group binds to the zinc ion replacing the hydroxyl ion. The sulfonamide oxygen closest to the zinc ion is 3.1 A away. Thus the tetrahedral geometry of the zinc is retained, refuting earlier models of a pentacoordinated zinc. The structure of the thiocyanate complex has been investigated at pH 8.5 and the structure has been refined at 1.9 A resolution using the least-squares refinement program PROLSQ. The crystallographic R factor is 17.6%. The zinc ion is pentacoordinated with the anion as well as a water molecule bound in addition to the three histidine residues. The nitrogen atom of the SCN- ion is 1.9 A from the zinc ion but shifted 1.3 A with respect to the hydroxyl ion in the native structure and at van der Waals' distance from the O gamma l atom of Thr-199. This is due to the inability of the O gamma l atom of Thr-199 to serve as a hydrogen bond donor, thus repelling the nonprotonated nitrogen. The SCN- molecule reaches into the deep end of the active site cavity where the sulfur atom has displaced the so-called "deep" water molecule of the native enzyme. The zinc-bound water molecule is 2.2 A from the zinc ion and 2.4 A from the SCN- nitrogen. In addition, this water is hydrogen bonded to the O gamma l atom of Thr-199 and to another water molecule. We have observed that solvent and inhibitor molecules have three possible binding sites on the zinc ion and their significance for the catalysis and inhibition of HCA II will be discussed. All available crystallographic data are consistent with a proposed catalytic mechanism in which both the OH moiety and one oxygen of the substrate HCO3- ion are ligated to the zinc ion.

Crystallographic studies of inhibitor binding sites in human carbonic anhydrase II: a pentacoordinated binding of the SCN- ion to the zinc at high pH.,Eriksson AE, Kylsten PM, Jones TA, Liljas A Proteins. 1988;4(4):283-93. PMID:3151020^[8]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Venta PJ, Welty RJ, Johnson TM, Sly WS, Tashian RE. Carbonic anhydrase II deficiency syndrome in a Belgian family is caused by a point mutation at an invariant histidine residue (107 His----Tyr): complete structure of the normal human CA II gene. Am J Hum Genet. 1991 Nov;49(5):1082-90. PMID:1928091
↑ Roth DE, Venta PJ, Tashian RE, Sly WS. Molecular basis of human carbonic anhydrase II deficiency. Proc Natl Acad Sci U S A. 1992 Mar 1;89(5):1804-8. PMID:1542674
↑ Soda H, Yukizane S, Yoshida I, Koga Y, Aramaki S, Kato H. A point mutation in exon 3 (His 107-->Tyr) in two unrelated Japanese patients with carbonic anhydrase II deficiency with central nervous system involvement. Hum Genet. 1996 Apr;97(4):435-7. PMID:8834238
↑ Hu PY, Lim EJ, Ciccolella J, Strisciuglio P, Sly WS. Seven novel mutations in carbonic anhydrase II deficiency syndrome identified by SSCP and direct sequencing analysis. Hum Mutat. 1997;9(5):383-7. PMID:9143915 doi:<383::AID-HUMU1>3.0.CO;2-5 10.1002/(SICI)1098-1004(1997)9:5<383::AID-HUMU1>3.0.CO;2-5
↑ Shah GN, Bonapace G, Hu PY, Strisciuglio P, Sly WS. Carbonic anhydrase II deficiency syndrome (osteopetrosis with renal tubular acidosis and brain calcification): novel mutations in CA2 identified by direct sequencing expand the opportunity for genotype-phenotype correlation. Hum Mutat. 2004 Sep;24(3):272. PMID:15300855 doi:10.1002/humu.9266
↑ Briganti F, Mangani S, Scozzafava A, Vernaglione G, Supuran CT. Carbonic anhydrase catalyzes cyanamide hydration to urea: is it mimicking the physiological reaction? J Biol Inorg Chem. 1999 Oct;4(5):528-36. PMID:10550681
↑ Kim CY, Whittington DA, Chang JS, Liao J, May JA, Christianson DW. Structural aspects of isozyme selectivity in the binding of inhibitors to carbonic anhydrases II and IV. J Med Chem. 2002 Feb 14;45(4):888-93. PMID:11831900
↑ Eriksson AE, Kylsten PM, Jones TA, Liljas A. Crystallographic studies of inhibitor binding sites in human carbonic anhydrase II: a pentacoordinated binding of the SCN- ion to the zinc at high pH. Proteins. 1988;4(4):283-93. PMID:3151020 doi:http://dx.doi.org/10.1002/prot.340040407

1 Structural highlights
2 Disease
3 Function
4 Evolutionary Conservation
5 Publication Abstract from PubMed
6 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/3ca2"

Categories: Carbonate dehydratase | Human | Eriksson, A E | Jones, T A | Liljas, A

@@ Line 1: / Line 1: @@
 ==CRYSTALLOGRAPHIC STUDIES OF INHIBITOR BINDING SITES IN HUMAN CARBONIC ANHYDRASE II. A PENTACOORDINATED BINDING OF THE SCN-ION TO THE ZINC AT HIGH P*H==
 <StructureSection load='3ca2' size='340' side='right' caption='[[3ca2]], [[Resolution|resolution]] 2.00&Aring;' scene=''>
@@ Line 5: / Line 6: @@
 </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=AMS:3-MERCURI-4-AMINOBENZENESULFONAMIDE'>AMS</scene>, <scene name='pdbligand=HG:MERCURY+(II)+ION'>HG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
 <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Carbonate_dehydratase Carbonate dehydratase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.2.1.1 4.2.1.1] </span></td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3ca2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3ca2 OCA], [http://pdbe.org/3ca2 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3ca2 RCSB], [http://www.ebi.ac.uk/pdbsum/3ca2 PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3ca2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3ca2 OCA], [http://pdbe.org/3ca2 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3ca2 RCSB], [http://www.ebi.ac.uk/pdbsum/3ca2 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3ca2 ProSAT]</span></td></tr>
 </table>
 == Disease ==
@@ Line 30: / Line 31: @@
 </div>
 <div class="pdbe-citations 3ca2" style="background-color:#fffaf0;"></div>
-==See Also==
-*[[Carbonic anhydrase|Carbonic anhydrase]]
 == References ==
 <references/>

3ca2

From Proteopedia

Revision as of 07:13, 29 November 2017

CRYSTALLOGRAPHIC STUDIES OF INHIBITOR BINDING SITES IN HUMAN CARBONIC ANHYDRASE II. A PENTACOORDINATED BINDING OF THE SCN-ION TO THE ZINC AT HIGH P*H

Structural highlights

Disease

Function

Evolutionary Conservation

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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