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==oxy T state haemoglobin: oxygen bound at all four haems==
==oxy T state haemoglobin: oxygen bound at all four haems==
<StructureSection load='1gzx' size='340' side='right' caption='[[1gzx]], [[Resolution|resolution]] 2.10&Aring;' scene=''>
<StructureSection load='1gzx' size='340' side='right'caption='[[1gzx]], [[Resolution|resolution]] 2.10&Aring;' scene=''>
== Structural highlights ==
== Structural highlights ==
<table><tr><td colspan='2'>[[1gzx]] 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=1GZX OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1GZX FirstGlance]. <br>
<table><tr><td colspan='2'>[[1gzx]] is a 4 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=1GZX OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1GZX FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene>, <scene name='pdbligand=OXY:OXYGEN+MOLECULE'>OXY</scene></td></tr>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.1&#8491;</td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1a00|1a00]], [[1a01|1a01]], [[1a0u|1a0u]], [[1a0v|1a0v]], [[1a0w|1a0w]], [[1a0x|1a0x]], [[1a0y|1a0y]], [[1a0z|1a0z]], [[1a3n|1a3n]], [[1a3o|1a3o]], [[1abw|1abw]], [[1aby|1aby]], [[1aj9|1aj9]], [[1axf|1axf]], [[1b86|1b86]], [[1bab|1bab]], [[1bbb|1bbb]], [[1bij|1bij]], [[1buw|1buw]], [[1bz0|1bz0]], [[1bz1|1bz1]], [[1bzz|1bzz]], [[1c7b|1c7b]], [[1c7c|1c7c]], [[1c7d|1c7d]], [[1cbl|1cbl]], [[1cbm|1cbm]], [[1cls|1cls]], [[1cmy|1cmy]], [[1coh|1coh]], [[1dke|1dke]], [[1dsh|1dsh]], [[1dxt|1dxt]], [[1dxu|1dxu]], [[1dxv|1dxv]], [[1g9v|1g9v]], [[1gbu|1gbu]], [[1gbv|1gbv]], [[1gli|1gli]], [[1hab|1hab]], [[1hac|1hac]], [[1hba|1hba]], [[1hbb|1hbb]], [[1hbs|1hbs]], [[1hco|1hco]], [[1hdb|1hdb]], [[1hga|1hga]], [[1hgb|1hgb]], [[1hgc|1hgc]], [[1hho|1hho]], [[1ird|1ird]], [[1j7s|1j7s]], [[1j7w|1j7w]], [[1j7y|1j7y]], [[1jy7|1jy7]], [[1k0y|1k0y]], [[1ljw|1ljw]], [[1nih|1nih]], [[1qi8|1qi8]], [[1qsh|1qsh]], [[1qsi|1qsi]], [[1rvw|1rvw]], [[1sdk|1sdk]], [[1sdl|1sdl]], [[1thb|1thb]], [[1vwt|1vwt]], [[2hbc|2hbc]], [[2hbd|2hbd]], [[2hbe|2hbe]], [[2hbf|2hbf]], [[2hbs|2hbs]], [[2hco|2hco]], [[2hhd|2hhd]], [[2hhe|2hhe]], [[4hhb|4hhb]], [[6hbw|6hbw]]</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene>, <scene name='pdbligand=OXY:OXYGEN+MOLECULE'>OXY</scene></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=1gzx FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1gzx OCA], [http://pdbe.org/1gzx PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1gzx RCSB], [http://www.ebi.ac.uk/pdbsum/1gzx PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1gzx ProSAT]</span></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=1gzx FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1gzx OCA], [https://pdbe.org/1gzx PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1gzx RCSB], [https://www.ebi.ac.uk/pdbsum/1gzx PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1gzx ProSAT]</span></td></tr>
</table>
</table>
== Disease ==
== Disease ==
[[http://www.uniprot.org/uniprot/HBA_HUMAN HBA_HUMAN]] Defects in HBA1 may be a cause of Heinz body anemias (HEIBAN) [MIM:[http://omim.org/entry/140700 140700]]. This is a form of non-spherocytic hemolytic anemia of Dacie type 1. After splenectomy, which has little benefit, basophilic inclusions called Heinz bodies are demonstrable in the erythrocytes. Before splenectomy, diffuse or punctate basophilia may be evident. Most of these cases are probably instances of hemoglobinopathy. The hemoglobin demonstrates heat lability. Heinz bodies are observed also with the Ivemark syndrome (asplenia with cardiovascular anomalies) and with glutathione peroxidase deficiency.<ref>PMID:2833478</ref>  Defects in HBA1 are the cause of alpha-thalassemia (A-THAL) [MIM:[http://omim.org/entry/604131 604131]]. The thalassemias are the most common monogenic diseases and occur mostly in Mediterranean and Southeast Asian populations. The hallmark of alpha-thalassemia is an imbalance in globin-chain production in the adult HbA molecule. The level of alpha chain production can range from none to very nearly normal levels. Deletion of both copies of each of the two alpha-globin genes causes alpha(0)-thalassemia, also known as homozygous alpha thalassemia. Due to the complete absence of alpha chains, the predominant fetal hemoglobin is a tetramer of gamma-chains (Bart hemoglobin) that has essentially no oxygen carrying capacity. This causes oxygen starvation in the fetal tissues leading to prenatal lethality or early neonatal death. The loss of three alpha genes results in high levels of a tetramer of four beta chains (hemoglobin H), causing a severe and life-threatening anemia known as hemoglobin H disease. Untreated, most patients die in childhood or early adolescence. The loss of two alpha genes results in mild alpha-thalassemia, also known as heterozygous alpha-thalassemia. Affected individuals have small red cells and a mild anemia (microcytosis). If three of the four alpha-globin genes are functional, individuals are completely asymptomatic. Some rare forms of alpha-thalassemia are due to point mutations (non-deletional alpha-thalassemia). The thalassemic phenotype is due to unstable globin alpha chains that are rapidly catabolized prior to formation of the alpha-beta heterotetramers.  Note=Alpha(0)-thalassemia is associated with non-immune hydrops fetalis, a generalized edema of the fetus with fluid accumulation in the body cavities due to non-immune causes. Non-immune hydrops fetalis is not a diagnosis in itself but a symptom, a feature of many genetic disorders, and the end-stage of a wide variety of disorders.  Defects in HBA1 are the cause of hemoglobin H disease (HBH) [MIM:[http://omim.org/entry/613978 613978]]. HBH is a form of alpha-thalassemia due to the loss of three alpha genes. This results in high levels of a tetramer of four beta chains (hemoglobin H), causing a severe and life-threatening anemia. Untreated, most patients die in childhood or early adolescence.<ref>PMID:10569720</ref> [[http://www.uniprot.org/uniprot/HBB_HUMAN HBB_HUMAN]] Defects in HBB may be a cause of Heinz body anemias (HEIBAN) [MIM:[http://omim.org/entry/140700 140700]]. This is a form of non-spherocytic hemolytic anemia of Dacie type 1. After splenectomy, which has little benefit, basophilic inclusions called Heinz bodies are demonstrable in the erythrocytes. Before splenectomy, diffuse or punctate basophilia may be evident. Most of these cases are probably instances of hemoglobinopathy. The hemoglobin demonstrates heat lability. Heinz bodies are observed also with the Ivemark syndrome (asplenia with cardiovascular anomalies) and with glutathione peroxidase deficiency.<ref>PMID:186485</ref> <ref>PMID:6259091</ref> <ref>PMID:2599881</ref> <ref>PMID:8704193</ref>  Defects in HBB are the cause of beta-thalassemia (B-THAL) [MIM:[http://omim.org/entry/613985 613985]]. A form of thalassemia. Thalassemias are common monogenic diseases occurring mostly in Mediterranean and Southeast Asian populations. The hallmark of beta-thalassemia is an imbalance in globin-chain production in the adult HbA molecule. Absence of beta chain causes beta(0)-thalassemia, while reduced amounts of detectable beta globin causes beta(+)-thalassemia. In the severe forms of beta-thalassemia, the excess alpha globin chains accumulate in the developing erythroid precursors in the marrow. Their deposition leads to a vast increase in erythroid apoptosis that in turn causes ineffective erythropoiesis and severe microcytic hypochromic anemia. Clinically, beta-thalassemia is divided into thalassemia major which is transfusion dependent, thalassemia intermedia (of intermediate severity), and thalassemia minor that is asymptomatic.<ref>PMID:1971109</ref>  Defects in HBB are the cause of sickle cell anemia (SKCA) [MIM:[http://omim.org/entry/603903 603903]]; also known as sickle cell disease. Sickle cell anemia is characterized by abnormally shaped red cells resulting in chronic anemia and periodic episodes of pain, serious infections and damage to vital organs. Normal red blood cells are round and flexible and flow easily through blood vessels, but in sickle cell anemia, the abnormal hemoglobin (called Hb S) causes red blood cells to become stiff. They are C-shaped and resembles a sickle. These stiffer red blood cells can led to microvascular occlusion thus cutting off the blood supply to nearby tissues.  Defects in HBB are the cause of beta-thalassemia dominant inclusion body type (B-THALIB) [MIM:[http://omim.org/entry/603902 603902]]. An autosomal dominant form of beta thalassemia characterized by moderate anemia, lifelong jaundice, cholelithiasis and splenomegaly, marked morphologic changes in the red cells, erythroid hyperplasia of the bone marrow with increased numbers of multinucleate red cell precursors, and the presence of large inclusion bodies in the normoblasts, both in the marrow and in the peripheral blood after splenectomy.<ref>PMID:1971109</ref> 
[https://www.uniprot.org/uniprot/HBA_HUMAN HBA_HUMAN] Defects in HBA1 may be a cause of Heinz body anemias (HEIBAN) [MIM:[https://omim.org/entry/140700 140700]. This is a form of non-spherocytic hemolytic anemia of Dacie type 1. After splenectomy, which has little benefit, basophilic inclusions called Heinz bodies are demonstrable in the erythrocytes. Before splenectomy, diffuse or punctate basophilia may be evident. Most of these cases are probably instances of hemoglobinopathy. The hemoglobin demonstrates heat lability. Heinz bodies are observed also with the Ivemark syndrome (asplenia with cardiovascular anomalies) and with glutathione peroxidase deficiency.<ref>PMID:2833478</ref>  Defects in HBA1 are the cause of alpha-thalassemia (A-THAL) [MIM:[https://omim.org/entry/604131 604131]. The thalassemias are the most common monogenic diseases and occur mostly in Mediterranean and Southeast Asian populations. The hallmark of alpha-thalassemia is an imbalance in globin-chain production in the adult HbA molecule. The level of alpha chain production can range from none to very nearly normal levels. Deletion of both copies of each of the two alpha-globin genes causes alpha(0)-thalassemia, also known as homozygous alpha thalassemia. Due to the complete absence of alpha chains, the predominant fetal hemoglobin is a tetramer of gamma-chains (Bart hemoglobin) that has essentially no oxygen carrying capacity. This causes oxygen starvation in the fetal tissues leading to prenatal lethality or early neonatal death. The loss of three alpha genes results in high levels of a tetramer of four beta chains (hemoglobin H), causing a severe and life-threatening anemia known as hemoglobin H disease. Untreated, most patients die in childhood or early adolescence. The loss of two alpha genes results in mild alpha-thalassemia, also known as heterozygous alpha-thalassemia. Affected individuals have small red cells and a mild anemia (microcytosis). If three of the four alpha-globin genes are functional, individuals are completely asymptomatic. Some rare forms of alpha-thalassemia are due to point mutations (non-deletional alpha-thalassemia). The thalassemic phenotype is due to unstable globin alpha chains that are rapidly catabolized prior to formation of the alpha-beta heterotetramers.  Note=Alpha(0)-thalassemia is associated with non-immune hydrops fetalis, a generalized edema of the fetus with fluid accumulation in the body cavities due to non-immune causes. Non-immune hydrops fetalis is not a diagnosis in itself but a symptom, a feature of many genetic disorders, and the end-stage of a wide variety of disorders.  Defects in HBA1 are the cause of hemoglobin H disease (HBH) [MIM:[https://omim.org/entry/613978 613978]. HBH is a form of alpha-thalassemia due to the loss of three alpha genes. This results in high levels of a tetramer of four beta chains (hemoglobin H), causing a severe and life-threatening anemia. Untreated, most patients die in childhood or early adolescence.<ref>PMID:10569720</ref>  
== Function ==
== Function ==
[[http://www.uniprot.org/uniprot/HBA_HUMAN HBA_HUMAN]] Involved in oxygen transport from the lung to the various peripheral tissues. [[http://www.uniprot.org/uniprot/HBB_HUMAN HBB_HUMAN]] Involved in oxygen transport from the lung to the various peripheral tissues.<ref>PMID:16904236</ref>  LVV-hemorphin-7 potentiates the activity of bradykinin, causing a decrease in blood pressure.<ref>PMID:16904236</ref> 
[https://www.uniprot.org/uniprot/HBA_HUMAN HBA_HUMAN] Involved in oxygen transport from the lung to the various peripheral tissues.
== Evolutionary Conservation ==
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
[[Image:Consurf_key_small.gif|200px|right]]
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</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=1gzx ConSurf].
</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=1gzx ConSurf].
<div style="clear:both"></div>
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The cooperative binding of oxygen by haemoglobin results from restraints on ligand binding in the T state. The unfavourable interactions made by the ligands at the haems destabilise the T state and favour the high affinity R state. The T &lt;==&gt; R equilibrium leads, in the presence of a ligand, to a rapid increase in the R state population and therefore generates cooperative binding. There is now considerable understanding of this phenomenon, but the interactions that reduce ligand affinity in the T state have not yet been fully explored, owing to the difficulties in preparing T state haemoglobin crystals in which all the subunits are oxygenated. A protocol has been developed to oxygenate deoxy T state adult human haemoglobin (HbA) crystals in air at 4 C at all four haems without significant loss of crystalline order. The X-ray crystal structure, determined to 2.1 A spacing, shows significant changes in the alpha and beta haem pockets as well as changes at the alpha(1)beta(2) interface in the direction of the R quaternary structure. Most of the shifts and deviations from deoxy T state HbA are similar to, but larger than, those previously observed in the T state met and other partially liganded T state forms. They provide clear evidence of haem-haem interaction in the T state.
Crystal structure of T state haemoglobin with oxygen bound at all four haems.,Paoli M, Liddington R, Tame J, Wilkinson A, Dodson G J Mol Biol. 1996 Mar 8;256(4):775-92. PMID:8642597<ref>PMID:8642597</ref>
From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 1gzx" style="background-color:#fffaf0;"></div>


==See Also==
==See Also==
*[[Ann Taylor/Hemoglobin|Ann Taylor/Hemoglobin]]
*[[Hemoglobin|Hemoglobin]]
*[[Hemoglobin 3D structures|Hemoglobin 3D structures]]
*[[Hemoglobin 3D structures|Hemoglobin 3D structures]]
*[[Sandbox 12345|Sandbox 12345]]
== References ==
== References ==
<references/>
<references/>
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</StructureSection>
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Homo sapiens]]
[[Category: Dodson, G]]
[[Category: Large Structures]]
[[Category: Liddington, R]]
[[Category: Dodson G]]
[[Category: Paoli, M]]
[[Category: Liddington R]]
[[Category: Tame, J]]
[[Category: Paoli M]]
[[Category: Wilkinson, A]]
[[Category: Tame J]]
[[Category: Cooperativity]]
[[Category: Wilkinson A]]
[[Category: Haem protein]]
[[Category: Oxygen binding]]
[[Category: Oxygen transport]]
[[Category: Transport]]

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