1k1k
From Proteopedia
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| - | [[Image:1k1k.gif|left|200px]]<br /> | + | [[Image:1k1k.gif|left|200px]]<br /><applet load="1k1k" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="1k1k" size=" | + | |
caption="1k1k, resolution 2.0Å" /> | caption="1k1k, resolution 2.0Å" /> | ||
'''Structure of Mutant Human Carbonmonoxyhemoglobin C (beta E6K) at 2.0 Angstrom Resolution in Phosphate Buffer.'''<br /> | '''Structure of Mutant Human Carbonmonoxyhemoglobin C (beta E6K) at 2.0 Angstrom Resolution in Phosphate Buffer.'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Previous studies have demonstrated that in vitro crystallization of | + | Previous studies have demonstrated that in vitro crystallization of R-state liganded hemoglobin C (HbC), a naturally occurring mutant human hemoglobin (betaE6K), in high-phosphate buffer solutions provides a potential model system for the intracellular crystallization of HbC associated with chronic hemolytic anemia in CC disease. The first high-resolution crystal structure of liganded HbC is reported here. HbC was crystallized from high phosphate and the structure of the carbonmonoxy-liganded R-state form was refined at 2.0 A resolution. Crystals exhibit diffraction consistent with the tetragonal space group P4(1)2(1)2, with unit-cell parameters a = 54.16, c = 195.30 A. The structure was solved by difference Fourier techniques and refinement by simulated annealing and restrained least-squares yielded a final R of 0.183 and an R(free) of 0.238 for all 19,382 unique reflections. The side chain of betaK6 exhibits very weak electron density consistent with significant mobility within the crystalline lattice. The highly dynamic nature of the side chain could potentially support a number of specific polar interactions that might reduce the barrier to crystallization and thus result in enhanced crystallization kinetics for HbC relative to HbA. Specifically, the NZ atom of the BK6 side chain could participate in an amino-aromatic hydrogen bond with the pi-electron cloud of betaH116 in a symmetry-related tetramer. BetaK6 NZ might also interact with the main-chain carbonyl O atom of betaH117 and the carboxylate group of betaE22 from a symmetry-related tetramer. |
==Disease== | ==Disease== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1K1K 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:// | + | 1K1K 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=1K1K OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
| - | [[Category: Almo, S | + | [[Category: Almo, S C.]] |
| - | [[Category: Dewan, J | + | [[Category: Dewan, J C.]] |
| - | [[Category: Hirsch, R | + | [[Category: Hirsch, R E.]] |
| - | [[Category: Nagel, R | + | [[Category: Nagel, R L.]] |
[[Category: Patskovska, L.]] | [[Category: Patskovska, L.]] | ||
[[Category: Patskovsky, Y.]] | [[Category: Patskovsky, Y.]] | ||
| - | [[Category: Puius, Y | + | [[Category: Puius, Y A.]] |
[[Category: Taylor-Feeling, A.]] | [[Category: Taylor-Feeling, A.]] | ||
[[Category: CMO]] | [[Category: CMO]] | ||
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[[Category: mutant human hemoglobin c(betae6k)]] | [[Category: mutant human hemoglobin c(betae6k)]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:29:04 2008'' |
Revision as of 11:29, 21 February 2008
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Structure of Mutant Human Carbonmonoxyhemoglobin C (beta E6K) at 2.0 Angstrom Resolution in Phosphate Buffer.
Contents |
Overview
Previous studies have demonstrated that in vitro crystallization of R-state liganded hemoglobin C (HbC), a naturally occurring mutant human hemoglobin (betaE6K), in high-phosphate buffer solutions provides a potential model system for the intracellular crystallization of HbC associated with chronic hemolytic anemia in CC disease. The first high-resolution crystal structure of liganded HbC is reported here. HbC was crystallized from high phosphate and the structure of the carbonmonoxy-liganded R-state form was refined at 2.0 A resolution. Crystals exhibit diffraction consistent with the tetragonal space group P4(1)2(1)2, with unit-cell parameters a = 54.16, c = 195.30 A. The structure was solved by difference Fourier techniques and refinement by simulated annealing and restrained least-squares yielded a final R of 0.183 and an R(free) of 0.238 for all 19,382 unique reflections. The side chain of betaK6 exhibits very weak electron density consistent with significant mobility within the crystalline lattice. The highly dynamic nature of the side chain could potentially support a number of specific polar interactions that might reduce the barrier to crystallization and thus result in enhanced crystallization kinetics for HbC relative to HbA. Specifically, the NZ atom of the BK6 side chain could participate in an amino-aromatic hydrogen bond with the pi-electron cloud of betaH116 in a symmetry-related tetramer. BetaK6 NZ might also interact with the main-chain carbonyl O atom of betaH117 and the carboxylate group of betaE22 from a symmetry-related tetramer.
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
1K1K is a Protein complex structure of sequences from Homo sapiens with and as ligands. Full crystallographic information is available from OCA.
Reference
Structure of mutant human carbonmonoxyhemoglobin C (betaE6K) at 2.0 A resolution., Dewan JC, Feeling-Taylor A, Puius YA, Patskovska L, Patskovsky Y, Nagel RL, Almo SC, Hirsch RE, Acta Crystallogr D Biol Crystallogr. 2002 Dec;58(Pt 12):2038-42. Epub 2002, Nov 23. PMID:12454462
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