2dn3: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image:2dn3.gif|left|200px]]<br /> | [[Image:2dn3.gif|left|200px]]<br /><applet load="2dn3" size="350" color="white" frame="true" align="right" spinBox="true" | ||
<applet load="2dn3" size=" | |||
caption="2dn3, resolution 1.25Å" /> | caption="2dn3, resolution 1.25Å" /> | ||
'''1.25A resolution crystal structure of human hemoglobin in the carbonmonoxy form'''<br /> | '''1.25A resolution crystal structure of human hemoglobin in the carbonmonoxy form'''<br /> | ||
==Overview== | ==Overview== | ||
The most recent refinement of the crystallographic structure of | The most recent refinement of the crystallographic structure of oxyhaemoglobin (oxyHb) was completed in 1983, and differences between this real-space refined model and later R state models have been interpreted as evidence of crystallisation artefacts, or numerous sub-states. We have refined models of deoxy, oxy and carbonmonoxy Hb to 1.25 A resolution each, and compare them with other Hb structures. It is shown that the older structures reflect the software used in refinement, and many differences with newer structures are unlikely to be physiologically relevant. The improved accuracy of our models clarifies the disagreement between NMR and X-ray studies of oxyHb, the NMR experiments suggesting a hydrogen bond to exist between the distal histidine and oxygen ligand of both the alpha and beta-subunits. The high-resolution crystal structure also reveals a hydrogen bond in both subunit types, but with subtly different geometry which may explain the very different behaviour when this residue is mutated to glycine in alpha or beta globin. We also propose a new set of relatively fixed residues to act as a frame of reference; this set contains a similar number of atoms to the well-known "BGH" frame yet shows a much smaller rmsd value between R and T state models of HbA. | ||
==Disease== | ==Disease== | ||
| Line 11: | Line 10: | ||
==About this Structure== | ==About this Structure== | ||
2DN3 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 HEM and CMO as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | 2DN3 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=HEM:'>HEM</scene> and <scene name='pdbligand=CMO:'>CMO</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2DN3 OCA]. | ||
==Reference== | ==Reference== | ||
| Line 17: | Line 16: | ||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Park, S | [[Category: Park, S Y.]] | ||
[[Category: Shibayama, N.]] | [[Category: Shibayama, N.]] | ||
[[Category: Shiro, Y.]] | [[Category: Shiro, Y.]] | ||
[[Category: Tame, J | [[Category: Tame, J R.]] | ||
[[Category: Yokoyama, T.]] | [[Category: Yokoyama, T.]] | ||
[[Category: CMO]] | [[Category: CMO]] | ||
| Line 28: | Line 27: | ||
[[Category: oxygen transport]] | [[Category: oxygen transport]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:00:33 2008'' | ||
Revision as of 18:00, 21 February 2008
|
1.25A resolution crystal structure of human hemoglobin in the carbonmonoxy form
OverviewOverview
The most recent refinement of the crystallographic structure of oxyhaemoglobin (oxyHb) was completed in 1983, and differences between this real-space refined model and later R state models have been interpreted as evidence of crystallisation artefacts, or numerous sub-states. We have refined models of deoxy, oxy and carbonmonoxy Hb to 1.25 A resolution each, and compare them with other Hb structures. It is shown that the older structures reflect the software used in refinement, and many differences with newer structures are unlikely to be physiologically relevant. The improved accuracy of our models clarifies the disagreement between NMR and X-ray studies of oxyHb, the NMR experiments suggesting a hydrogen bond to exist between the distal histidine and oxygen ligand of both the alpha and beta-subunits. The high-resolution crystal structure also reveals a hydrogen bond in both subunit types, but with subtly different geometry which may explain the very different behaviour when this residue is mutated to glycine in alpha or beta globin. We also propose a new set of relatively fixed residues to act as a frame of reference; this set contains a similar number of atoms to the well-known "BGH" frame yet shows a much smaller rmsd value between R and T state models of HbA.
DiseaseDisease
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 StructureAbout this Structure
2DN3 is a Protein complex structure of sequences from Homo sapiens with and as ligands. Full crystallographic information is available from OCA.
ReferenceReference
1.25 A resolution crystal structures of human haemoglobin in the oxy, deoxy and carbonmonoxy forms., Park SY, Yokoyama T, Shibayama N, Shiro Y, Tame JR, J Mol Biol. 2006 Jul 14;360(3):690-701. Epub 2006 May 30. PMID:16765986
Page seeded by OCA on Thu Feb 21 17:00:33 2008