|
|
| (17 intermediate revisions not shown.) |
| Line 1: |
Line 1: |
| - | [[Image:2fnn.gif|left|200px]]<br /> | |
| - | <applet load="2fnn" size="450" color="white" frame="true" align="right" spinBox="true" | |
| - | caption="2fnn, resolution 1.8Å" /> | |
| - | '''Activation of human carbonic anhydrase II by exogenous proton donors'''<br /> | |
| | | | |
| - | ==Overview== | + | ==Activation of human carbonic anhydrase II by exogenous proton donors== |
| - | Small molecule rescue of mutant forms of human carbonic anhydrase II (HCA, II) occurs by participation of exogenous donors/acceptors in the proton, transfer pathway between the zinc-bound water and solution. To examine, more thoroughly the energetics of this activation, we have constructed a, mutant, H64W HCA II, which we have shown is activated by 4-methylimidazole, (4-MI) by a mechanism involving the binding of 4-MI to the side chain of, Trp-64 approximately 8 A from the zinc. A series of experiments are, consistent with the activation of H64W HCA II by the interaction of, imidazole and pyridine derivatives as exogenous proton donors with the, indole ring of Trp-64; these experiments include pH profiles and H/D, solvent isotope effects consistent with proton transfer, observation of, approximately fourfold greater activation with the mutant containing, Trp-64 compared with Gly-64, and the observation by x-ray crystallography, of the binding of 4-MI associated with the indole side chain of Trp-64 in, W5A-H64W HCA II. Proton donors bound at the less flexible side chain of, Trp-64 in W5A-H64W HCA II do not show activation, but such donors bound at, the more flexible Trp-64 of H64W HCA II do show activation, supporting, suggestions that conformational mobility of the binding site is associated, with more efficient proton transfer. Evaluation using Marcus theory showed, that the activation of H64W HCA II by these proton donors was reflected in, the work functions w(r) and w(p) rather than in the intrinsic Marcus, barrier itself, consistent with the role of solvent reorganization in, catalysis. | + | <StructureSection load='2fnn' size='340' side='right'caption='[[2fnn]], [[Resolution|resolution]] 1.80Å' scene=''> |
| | + | == Structural highlights == |
| | + | <table><tr><td colspan='2'>[[2fnn]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2FNN OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2FNN FirstGlance]. <br> |
| | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.8Å</td></tr> |
| | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=4MZ:4-METHYLIMIDAZOLE'>4MZ</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr> |
| | + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2fnn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2fnn OCA], [https://pdbe.org/2fnn PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2fnn RCSB], [https://www.ebi.ac.uk/pdbsum/2fnn PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2fnn ProSAT]</span></td></tr> |
| | + | </table> |
| | + | == Disease == |
| | + | [https://www.uniprot.org/uniprot/CAH2_HUMAN CAH2_HUMAN] Defects in CA2 are the cause of osteopetrosis autosomal recessive type 3 (OPTB3) [MIM:[https://omim.org/entry/259730 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.<ref>PMID:1928091</ref> <ref>PMID:1542674</ref> <ref>PMID:8834238</ref> <ref>PMID:9143915</ref> <ref>PMID:15300855</ref> |
| | + | == Function == |
| | + | [https://www.uniprot.org/uniprot/CAH2_HUMAN 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.<ref>PMID:10550681</ref> <ref>PMID:11831900</ref> |
| | + | == Evolutionary Conservation == |
| | + | [[Image:Consurf_key_small.gif|200px|right]] |
| | + | Check<jmol> |
| | + | <jmolCheckbox> |
| | + | <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/fn/2fnn_consurf.spt"</scriptWhenChecked> |
| | + | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> |
| | + | <text>to colour the structure by Evolutionary Conservation</text> |
| | + | </jmolCheckbox> |
| | + | </jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=2fnn ConSurf]. |
| | + | <div style="clear:both"></div> |
| | + | <div style="background-color:#fffaf0;"> |
| | + | == Publication Abstract from PubMed == |
| | + | Small molecule rescue of mutant forms of human carbonic anhydrase II (HCA II) occurs by participation of exogenous donors/acceptors in the proton transfer pathway between the zinc-bound water and solution. To examine more thoroughly the energetics of this activation, we have constructed a mutant, H64W HCA II, which we have shown is activated by 4-methylimidazole (4-MI) by a mechanism involving the binding of 4-MI to the side chain of Trp-64 approximately 8 A from the zinc. A series of experiments are consistent with the activation of H64W HCA II by the interaction of imidazole and pyridine derivatives as exogenous proton donors with the indole ring of Trp-64; these experiments include pH profiles and H/D solvent isotope effects consistent with proton transfer, observation of approximately fourfold greater activation with the mutant containing Trp-64 compared with Gly-64, and the observation by x-ray crystallography of the binding of 4-MI associated with the indole side chain of Trp-64 in W5A-H64W HCA II. Proton donors bound at the less flexible side chain of Trp-64 in W5A-H64W HCA II do not show activation, but such donors bound at the more flexible Trp-64 of H64W HCA II do show activation, supporting suggestions that conformational mobility of the binding site is associated with more efficient proton transfer. Evaluation using Marcus theory showed that the activation of H64W HCA II by these proton donors was reflected in the work functions w(r) and w(p) rather than in the intrinsic Marcus barrier itself, consistent with the role of solvent reorganization in catalysis. |
| | | | |
| - | ==Disease==
| + | Location of binding sites in small molecule rescue of human carbonic anhydrase II.,Bhatt D, Fisher SZ, Tu C, McKenna R, Silverman DN Biophys J. 2007 Jan 15;92(2):562-70. Epub 2006 Oct 27. PMID:17071654<ref>PMID:17071654</ref> |
| - | Known disease associated with this structure: Osteopetrosis, autosomal recessive 3, with renal tubular acidosis OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=611492 611492]]
| + | |
| | | | |
| - | ==About this Structure==
| + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> |
| - | 2FNN is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with ZN and 4MZ as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [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] Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2FNN OCA].
| + | </div> |
| | + | <div class="pdbe-citations 2fnn" style="background-color:#fffaf0;"></div> |
| | | | |
| - | ==Reference== | + | ==See Also== |
| - | Location of binding sites in small molecule rescue of human carbonic anhydrase II., Bhatt D, Fisher SZ, Tu C, McKenna R, Silverman DN, Biophys J. 2007 Jan 15;92(2):562-70. Epub 2006 Oct 27. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=17071654 17071654]
| + | *[[Carbonic anhydrase 3D structures|Carbonic anhydrase 3D structures]] |
| - | [[Category: Carbonate dehydratase]] | + | == References == |
| | + | <references/> |
| | + | __TOC__ |
| | + | </StructureSection> |
| | [[Category: Homo sapiens]] | | [[Category: Homo sapiens]] |
| - | [[Category: Single protein]] | + | [[Category: Large Structures]] |
| - | [[Category: Bhatt, D.]] | + | [[Category: Bhatt D]] |
| - | [[Category: Fisher, S.Z.]] | + | [[Category: Fisher SZ]] |
| - | [[Category: McKenna, R.]] | + | [[Category: McKenna R]] |
| - | [[Category: Silverman, D.N.]] | + | [[Category: Silverman DN]] |
| - | [[Category: Tu, C.]] | + | [[Category: Tu C]] |
| - | [[Category: 4MZ]]
| + | |
| - | [[Category: ZN]]
| + | |
| - | [[Category: carbonic anhydrase]]
| + | |
| - | [[Category: exogenous proton donor]]
| + | |
| - | [[Category: proton transfer]]
| + | |
| - | | + | |
| - | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Mon Nov 12 22:08:14 2007''
| + | |
| Structural highlights
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
Small molecule rescue of mutant forms of human carbonic anhydrase II (HCA II) occurs by participation of exogenous donors/acceptors in the proton transfer pathway between the zinc-bound water and solution. To examine more thoroughly the energetics of this activation, we have constructed a mutant, H64W HCA II, which we have shown is activated by 4-methylimidazole (4-MI) by a mechanism involving the binding of 4-MI to the side chain of Trp-64 approximately 8 A from the zinc. A series of experiments are consistent with the activation of H64W HCA II by the interaction of imidazole and pyridine derivatives as exogenous proton donors with the indole ring of Trp-64; these experiments include pH profiles and H/D solvent isotope effects consistent with proton transfer, observation of approximately fourfold greater activation with the mutant containing Trp-64 compared with Gly-64, and the observation by x-ray crystallography of the binding of 4-MI associated with the indole side chain of Trp-64 in W5A-H64W HCA II. Proton donors bound at the less flexible side chain of Trp-64 in W5A-H64W HCA II do not show activation, but such donors bound at the more flexible Trp-64 of H64W HCA II do show activation, supporting suggestions that conformational mobility of the binding site is associated with more efficient proton transfer. Evaluation using Marcus theory showed that the activation of H64W HCA II by these proton donors was reflected in the work functions w(r) and w(p) rather than in the intrinsic Marcus barrier itself, consistent with the role of solvent reorganization in catalysis.
Location of binding sites in small molecule rescue of human carbonic anhydrase II.,Bhatt D, Fisher SZ, Tu C, McKenna R, Silverman DN Biophys J. 2007 Jan 15;92(2):562-70. Epub 2006 Oct 27. PMID:17071654[8]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
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
- ↑ Bhatt D, Fisher SZ, Tu C, McKenna R, Silverman DN. Location of binding sites in small molecule rescue of human carbonic anhydrase II. Biophys J. 2007 Jan 15;92(2):562-70. Epub 2006 Oct 27. PMID:17071654 doi:http://dx.doi.org/10.1529/biophysj.106.093203
|
