2hz2: Difference between revisions
No edit summary |
No edit summary |
||
| Line 3: | Line 3: | ||
<StructureSection load='2hz2' size='340' side='right'caption='[[2hz2]], [[Resolution|resolution]] 2.00Å' scene=''> | <StructureSection load='2hz2' size='340' side='right'caption='[[2hz2]], [[Resolution|resolution]] 2.00Å' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[2hz2]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/ | <table><tr><td colspan='2'>[[2hz2]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Synechocystis_sp._PCC_6803 Synechocystis sp. PCC 6803]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2HZ2 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2HZ2 FirstGlance]. <br> | ||
</td></tr><tr id=' | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2Å</td></tr> | ||
<tr id=' | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CD:CADMIUM+ION'>CD</scene>, <scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</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=2hz2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2hz2 OCA], [https://pdbe.org/2hz2 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2hz2 RCSB], [https://www.ebi.ac.uk/pdbsum/2hz2 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2hz2 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=2hz2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2hz2 OCA], [https://pdbe.org/2hz2 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2hz2 RCSB], [https://www.ebi.ac.uk/pdbsum/2hz2 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2hz2 ProSAT]</span></td></tr> | ||
</table> | </table> | ||
== Function == | == Function == | ||
[https://www.uniprot.org/uniprot/TRHBN_SYNY3 TRHBN_SYNY3] Forms a very stable complex with oxygen. The oxygen dissociation rate is 0.011 s(-1). | |||
== Evolutionary Conservation == | == Evolutionary Conservation == | ||
[[Image:Consurf_key_small.gif|200px|right]] | [[Image:Consurf_key_small.gif|200px|right]] | ||
| Line 38: | Line 37: | ||
</StructureSection> | </StructureSection> | ||
[[Category: Large Structures]] | [[Category: Large Structures]] | ||
[[Category: | [[Category: Synechocystis sp. PCC 6803]] | ||
[[Category: | [[Category: Hoy JA]] | ||
Latest revision as of 13:03, 30 August 2023
The x-ray crystal structure of ferric Synechocystis hemoglobin H117A mutant with a covalent linkageThe x-ray crystal structure of ferric Synechocystis hemoglobin H117A mutant with a covalent linkage
Structural highlights
FunctionTRHBN_SYNY3 Forms a very stable complex with oxygen. The oxygen dissociation rate is 0.011 s(-1). 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 PubMedSynechocystis hemoglobin contains an unprecedented covalent bond between a nonaxial histidine side chain (H117) and the heme 2-vinyl. This bond has been previously shown to stabilize the ferric protein against denaturation, and also to affect the kinetics of cyanide association. However, it is unclear why Synechocystis hemoglobin would require the additional degree of stabilization accompanying the His117-heme 2-vinyl bond because it also displays endogenous bis-histidyl axial heme coordination, which should greatly assist heme retention. Furthermore, the mechanism by which the His117-heme 2-vinyl bond affects ligand binding has not been reported, nor has any investigation of the role of this bond on the structure and function of the protein in the ferrous oxidation state. Here we report an investigation of the role of the Synechocystis hemoglobin His117-heme 2-vinyl bond on structure, heme coordination, exogenous ligand binding, and stability in both the ferrous and ferric oxidation states. Our results reveal that hexacoordinate Synechocystis hemoglobin lacking this bond is less stable in the ferrous oxidation state than the ferric, which is surprising in light of our understanding of pentacoordinate Hb stability, in which the ferric protein is always less stable. It is also demonstrated that removal of the His117-heme 2-vinyl bond increases the affinity constant for intramolecular histidine coordination in the ferric oxidation state, thus presenting greater competition for the ligand binding site and lowering the observed rate and affinity constants for exogenous ligands. Covalent heme attachment in Synechocystis hemoglobin is required to prevent ferrous heme dissociation.,Hoy JA, Smagghe BJ, Halder P, Hargrove MS Protein Sci. 2007 Feb;16(2):250-60. PMID:17242429[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|
| ||||||||||||||||||