1coh
From Proteopedia
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|PDB= 1coh |SIZE=350|CAPTION= <scene name='initialview01'>1coh</scene>, resolution 2.9Å | |PDB= 1coh |SIZE=350|CAPTION= <scene name='initialview01'>1coh</scene>, resolution 2.9Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand= | + | |LIGAND= <scene name='pdbligand=CMO:CARBON+MONOXIDE'>CMO</scene>, <scene name='pdbligand=COH:PROTOPORPHYRIN+IX+CONTAINING+CO'>COH</scene>, <scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene> |
|ACTIVITY= | |ACTIVITY= | ||
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1coh FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1coh OCA], [http://www.ebi.ac.uk/pdbsum/1coh PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1coh RCSB]</span> | ||
}} | }} | ||
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==Overview== | ==Overview== | ||
We report the X-ray crystal structure of two analogues of human haemoglobin in the deoxy quaternary (T) state with ligand bound exclusively at the alpha haems. These models were prepared from symmetric, mixed-metal hybrid haemoglobin molecules. The structures of alpha Fe(II) beta Co(II), its carbonmonoxy derivative alpha Fe(II)CO beta Co(II), and alpha Fe(II)O2 beta Ni(II) are compared with native deoxy haemoglobin by difference Fourier syntheses at 2.8, 2.9 and 3.5 A resolution, respectively, and the refined alpha Fe(II)CO beta Co(II) structure is analysed. In both the native deoxy and liganded T molecules, the mean plane of the alpha-subunit haem is parallel with the axis of the F helix, but this plane is tilted with respect to the helix axis in the oxy-quaternary R state. The side-chains of LeuFG3 and ValFG5 sterically restrict haem tilting in the T state. We propose that strain energy develops at the contact between the haem and these residues in the liganded T-state haemoglobin, and that the strain is, in part, responsible for the low affinity of the T-state alpha haem. | We report the X-ray crystal structure of two analogues of human haemoglobin in the deoxy quaternary (T) state with ligand bound exclusively at the alpha haems. These models were prepared from symmetric, mixed-metal hybrid haemoglobin molecules. The structures of alpha Fe(II) beta Co(II), its carbonmonoxy derivative alpha Fe(II)CO beta Co(II), and alpha Fe(II)O2 beta Ni(II) are compared with native deoxy haemoglobin by difference Fourier syntheses at 2.8, 2.9 and 3.5 A resolution, respectively, and the refined alpha Fe(II)CO beta Co(II) structure is analysed. In both the native deoxy and liganded T molecules, the mean plane of the alpha-subunit haem is parallel with the axis of the F helix, but this plane is tilted with respect to the helix axis in the oxy-quaternary R state. The side-chains of LeuFG3 and ValFG5 sterically restrict haem tilting in the T state. We propose that strain energy develops at the contact between the haem and these residues in the liganded T-state haemoglobin, and that the strain is, in part, responsible for the low affinity of the T-state alpha haem. | ||
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| - | ==Disease== | ||
| - | Known diseases associated with this structure: Erythremias, alpha- OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=141800 141800]], Erythremias, beta- OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=141900 141900]], Erythrocytosis OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=141850 141850]], HPFH, deletion type OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=141900 141900]], Heinz body anemia OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=141850 141850]], Heinz body anemias, alpha- OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=141800 141800]], Heinz body anemias, beta- OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=141900 141900]], Hemoglobin H disease OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=141850 141850]], Hypochromic microcytic anemia OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=141850 141850]], Methemoglobinemias, alpha- OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=141800 141800]], Methemoglobinemias, beta- OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=141900 141900]], Sickle cell anemia OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=141900 141900]], Thalassemia, alpha- OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=141850 141850]], Thalassemia-beta, dominant inclusion-body OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=141900 141900]], Thalassemias, alpha- OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=141800 141800]], Thalassemias, beta- OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=141900 141900]] | ||
==About this Structure== | ==About this Structure== | ||
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[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Luisi, B.]] | [[Category: Luisi, B.]] | ||
| - | [[Category: CMO]] | ||
| - | [[Category: COH]] | ||
| - | [[Category: HEM]] | ||
[[Category: oxygen transport]] | [[Category: oxygen transport]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 19:25:37 2008'' |
Revision as of 16:25, 30 March 2008
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| , resolution 2.9Å | |||||||
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| Ligands: | , , | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
STRUCTURE OF HAEMOGLOBIN IN THE DEOXY QUATERNARY STATE WITH LIGAND BOUND AT THE ALPHA HAEMS
Overview
We report the X-ray crystal structure of two analogues of human haemoglobin in the deoxy quaternary (T) state with ligand bound exclusively at the alpha haems. These models were prepared from symmetric, mixed-metal hybrid haemoglobin molecules. The structures of alpha Fe(II) beta Co(II), its carbonmonoxy derivative alpha Fe(II)CO beta Co(II), and alpha Fe(II)O2 beta Ni(II) are compared with native deoxy haemoglobin by difference Fourier syntheses at 2.8, 2.9 and 3.5 A resolution, respectively, and the refined alpha Fe(II)CO beta Co(II) structure is analysed. In both the native deoxy and liganded T molecules, the mean plane of the alpha-subunit haem is parallel with the axis of the F helix, but this plane is tilted with respect to the helix axis in the oxy-quaternary R state. The side-chains of LeuFG3 and ValFG5 sterically restrict haem tilting in the T state. We propose that strain energy develops at the contact between the haem and these residues in the liganded T-state haemoglobin, and that the strain is, in part, responsible for the low affinity of the T-state alpha haem.
About this Structure
1COH is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Structure of haemoglobin in the deoxy quaternary state with ligand bound at the alpha haems., Luisi B, Shibayama N, J Mol Biol. 1989 Apr 20;206(4):723-36. PMID:2738915
Page seeded by OCA on Sun Mar 30 19:25:37 2008
