1shr: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image: | ==Crystal structure of ferrocyanide bound human hemoglobin A2 at 1.88A resolution== | ||
<StructureSection load='1shr' size='340' side='right' caption='[[1shr]], [[Resolution|resolution]] 1.88Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[1shr]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1SHR OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1SHR FirstGlance]. <br> | |||
</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CYN:CYANIDE+ION'>CYN</scene>, <scene name='pdbligand=FE:FE+(III)+ION'>FE</scene>, <scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene><br> | |||
<tr><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1si4|1si4]]</td></tr> | |||
<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1shr FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1shr OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1shr RCSB], [http://www.ebi.ac.uk/pdbsum/1shr PDBsum]</span></td></tr> | |||
<table> | |||
== 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/sh/1shr_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/chain_selection.php?pdb_ID=2ata ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
Hemoglobin A(2) (alpha(2)delta(2)) is an important hemoglobin variant which is a minor component (2-3%) in the circulating red blood cells, and its elevated concentration in beta-thalassemia is a useful clinical diagnostic. In beta-thalassemia major, where there is beta-chain production failure, HbA(2) acts as the predominant oxygen deliverer. HbA(2) has two more important features. (1) It is more resistant to thermal denaturation than HbA, and (2) it inhibits the polymerization of deoxy sickle hemoglobin (HbS). Hemoglobin E (E26K(beta)), formed as a result of the splice site mutation on exon 1 of the beta-globin gene, is another important hemoglobin variant which is known to be unstable at high temperatures. Both heterozygous HbE (HbAE) and homozygous HbE (HbEE) are benign disorders, but when HbE combines with beta-thalassemia, it causes E/beta-thalassemia which has severe clinical consequences. In this paper, we present the crystal structures of HbA(2) and HbE at 2.20 and 1.74 A resolution, respectively, in their R2 states, which have been used here to provide the probable explanations of the thermal stability and instability of HbA(2) and HbE. Using the coordinates of R2 state HbA(2), we modeled the structure of T state HbA(2) which allowed us to address the structural basis of the antisickling property of HbA(2). Using the coordinates of the delta-chain of HbA(2) (R2 state), we also modeled the structure of hemoglobin homotetramer delta(4) that occurs in the case of rare HbH disease. From the differences in intersubunit contacts among beta(4), gamma(4), and delta(4), we formed a hypothesis regarding the possible tetramerization pathway of delta(4). The crystal structure of a ferrocyanide-bound HbA(2) at 1.88 A resolution is also presented here, which throws light on the location and the mode of binding of ferrocyanide anion with hemoglobin, predominantly using the residues involved in DPG binding. The pH dependence of ferrocyanide binding with hemoglobin has also been investigated. | |||
Crystal structures of HbA2 and HbE and modeling of hemoglobin delta 4: interpretation of the thermal stability and the antisickling effect of HbA2 and identification of the ferrocyanide binding site in Hb.,Sen U, Dasgupta J, Choudhury D, Datta P, Chakrabarti A, Chakrabarty SB, Chakrabarty A, Dattagupta JK Biochemistry. 2004 Oct 5;43(39):12477-88. PMID:15449937<ref>PMID:15449937</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
==See Also== | ==See Also== | ||
*[[Hemoglobin|Hemoglobin]] | *[[Hemoglobin 3D structures|Hemoglobin 3D structures]] | ||
== References == | |||
== | <references/> | ||
< | __TOC__ | ||
</StructureSection> | |||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Chakrabarti, A.]] | [[Category: Chakrabarti, A.]] | ||
Revision as of 01:10, 29 September 2014
Crystal structure of ferrocyanide bound human hemoglobin A2 at 1.88A resolutionCrystal structure of ferrocyanide bound human hemoglobin A2 at 1.88A resolution
Structural highlights
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 PubMedHemoglobin A(2) (alpha(2)delta(2)) is an important hemoglobin variant which is a minor component (2-3%) in the circulating red blood cells, and its elevated concentration in beta-thalassemia is a useful clinical diagnostic. In beta-thalassemia major, where there is beta-chain production failure, HbA(2) acts as the predominant oxygen deliverer. HbA(2) has two more important features. (1) It is more resistant to thermal denaturation than HbA, and (2) it inhibits the polymerization of deoxy sickle hemoglobin (HbS). Hemoglobin E (E26K(beta)), formed as a result of the splice site mutation on exon 1 of the beta-globin gene, is another important hemoglobin variant which is known to be unstable at high temperatures. Both heterozygous HbE (HbAE) and homozygous HbE (HbEE) are benign disorders, but when HbE combines with beta-thalassemia, it causes E/beta-thalassemia which has severe clinical consequences. In this paper, we present the crystal structures of HbA(2) and HbE at 2.20 and 1.74 A resolution, respectively, in their R2 states, which have been used here to provide the probable explanations of the thermal stability and instability of HbA(2) and HbE. Using the coordinates of R2 state HbA(2), we modeled the structure of T state HbA(2) which allowed us to address the structural basis of the antisickling property of HbA(2). Using the coordinates of the delta-chain of HbA(2) (R2 state), we also modeled the structure of hemoglobin homotetramer delta(4) that occurs in the case of rare HbH disease. From the differences in intersubunit contacts among beta(4), gamma(4), and delta(4), we formed a hypothesis regarding the possible tetramerization pathway of delta(4). The crystal structure of a ferrocyanide-bound HbA(2) at 1.88 A resolution is also presented here, which throws light on the location and the mode of binding of ferrocyanide anion with hemoglobin, predominantly using the residues involved in DPG binding. The pH dependence of ferrocyanide binding with hemoglobin has also been investigated. Crystal structures of HbA2 and HbE and modeling of hemoglobin delta 4: interpretation of the thermal stability and the antisickling effect of HbA2 and identification of the ferrocyanide binding site in Hb.,Sen U, Dasgupta J, Choudhury D, Datta P, Chakrabarti A, Chakrabarty SB, Chakrabarty A, Dattagupta JK Biochemistry. 2004 Oct 5;43(39):12477-88. PMID:15449937[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|
| ||||||||||||||||||