1j40
From Proteopedia
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- | [[Image:1j40.gif|left|200px]]<br /> | + | [[Image:1j40.gif|left|200px]]<br /><applet load="1j40" size="350" color="white" frame="true" align="right" spinBox="true" |
- | <applet load="1j40" size=" | + | |
caption="1j40, resolution 1.45Å" /> | caption="1j40, resolution 1.45Å" /> | ||
'''Direct observation of photolysis-induced tertiary structural changes in human haemoglobin; Crystal structure of alpha(Ni)-beta(Fe-CO) hemoglobin (laser unphotolysed)'''<br /> | '''Direct observation of photolysis-induced tertiary structural changes in human haemoglobin; Crystal structure of alpha(Ni)-beta(Fe-CO) hemoglobin (laser unphotolysed)'''<br /> | ||
==Overview== | ==Overview== | ||
- | Human Hb, an alpha2beta2 tetrameric oxygen transport protein that switches | + | Human Hb, an alpha2beta2 tetrameric oxygen transport protein that switches from a T (tense) to an R (relaxed) quaternary structure during oxygenation, has long served as a model for studying protein allostery in general. Time-resolved spectroscopic measurements after photodissociation of CO-liganded Hb have played a central role in exploring both protein dynamical responses and molecular cooperativity, but the direct visualization and the structural consequences of photodeligation have not yet been reported. Here we present an x-ray study of structural changes induced by photodissociation of half-liganded T-state and fully liganded R-state human Hb at cryogenic temperatures (25-35 K). On photodissociation of CO, structural changes involving the heme and the F-helix are more marked in the alpha subunit than in the beta subunit, and more subtle in the R state than in the T state. Photodeligation causes a significant sliding motion of the T-state beta heme. Our results establish that the structural basis of the low affinity of the T state is radically different between the subunits, because of differences in the packing and chemical tension at the hemes. |
==Disease== | ==Disease== | ||
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==About this Structure== | ==About this Structure== | ||
- | 1J40 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with HNI, HEM, CMO and 2FU as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1J40 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with <scene name='pdbligand=HNI:'>HNI</scene>, <scene name='pdbligand=HEM:'>HEM</scene>, <scene name='pdbligand=CMO:'>CMO</scene> and <scene name='pdbligand=2FU:'>2FU</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1J40 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Adachi, S.]] | [[Category: Adachi, S.]] | ||
- | [[Category: Park, S | + | [[Category: Park, S Y.]] |
- | [[Category: RSGI, RIKEN | + | [[Category: RSGI, RIKEN Structural Genomics/Proteomics Initiative.]] |
[[Category: Shibayama, N.]] | [[Category: Shibayama, N.]] | ||
[[Category: Shiro, Y.]] | [[Category: Shiro, Y.]] | ||
- | [[Category: Tame, J | + | [[Category: Tame, J R.H.]] |
[[Category: 2FU]] | [[Category: 2FU]] | ||
[[Category: CMO]] | [[Category: CMO]] | ||
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[[Category: tertiary structure changes]] | [[Category: tertiary structure changes]] | ||
- | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:18:42 2008'' |
Revision as of 11:18, 21 February 2008
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Direct observation of photolysis-induced tertiary structural changes in human haemoglobin; Crystal structure of alpha(Ni)-beta(Fe-CO) hemoglobin (laser unphotolysed)
Contents |
Overview
Human Hb, an alpha2beta2 tetrameric oxygen transport protein that switches from a T (tense) to an R (relaxed) quaternary structure during oxygenation, has long served as a model for studying protein allostery in general. Time-resolved spectroscopic measurements after photodissociation of CO-liganded Hb have played a central role in exploring both protein dynamical responses and molecular cooperativity, but the direct visualization and the structural consequences of photodeligation have not yet been reported. Here we present an x-ray study of structural changes induced by photodissociation of half-liganded T-state and fully liganded R-state human Hb at cryogenic temperatures (25-35 K). On photodissociation of CO, structural changes involving the heme and the F-helix are more marked in the alpha subunit than in the beta subunit, and more subtle in the R state than in the T state. Photodeligation causes a significant sliding motion of the T-state beta heme. Our results establish that the structural basis of the low affinity of the T state is radically different between the subunits, because of differences in the packing and chemical tension at the hemes.
Disease
Known diseases associated with this structure: Erythremias, alpha- OMIM:[141800], Erythremias, beta- OMIM:[141900], Erythrocytosis OMIM:[141850], HPFH, deletion type OMIM:[141900], Heinz body anemia OMIM:[141850], Heinz body anemias, alpha- OMIM:[141800], Heinz body anemias, beta- OMIM:[141900], Hemoglobin H disease OMIM:[141850], Hypochromic microcytic anemia OMIM:[141850], Methemoglobinemias, alpha- OMIM:[141800], Methemoglobinemias, beta- OMIM:[141900], Sickle cell anemia OMIM:[141900], Thalassemia, alpha- OMIM:[141850], Thalassemia-beta, dominant inclusion-body OMIM:[141900], Thalassemias, alpha- OMIM:[141800], Thalassemias, beta- OMIM:[141900]
About this Structure
1J40 is a Protein complex structure of sequences from Homo sapiens with , , and as ligands. Full crystallographic information is available from OCA.
Reference
Direct observation of photolysis-induced tertiary structural changes in hemoglobin., Adachi S, Park SY, Tame JR, Shiro Y, Shibayama N, Proc Natl Acad Sci U S A. 2003 Jun 10;100(12):7039-44. Epub 2003 May 28. PMID:12773618
Page seeded by OCA on Thu Feb 21 13:18:42 2008
Categories: Homo sapiens | Protein complex | Adachi, S. | Park, S Y. | RSGI, RIKEN Structural Genomics/Proteomics Initiative. | Shibayama, N. | Shiro, Y. | Tame, J R.H. | 2FU | CMO | HEM | HNI | Crystal photolysis | Riken structural genomics/proteomics initiative | Rsgi | Structural genomics | Tertiary structure changes