1pyz
From Proteopedia
(New page: 200px<br /><applet load="1pyz" size="450" color="white" frame="true" align="right" spinBox="true" caption="1pyz, resolution 1.25Å" /> '''CRYSTALLOGRAPHIC STR...) |
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| - | [[Image:1pyz.jpg|left|200px]]<br /><applet load="1pyz" size=" | + | [[Image:1pyz.jpg|left|200px]]<br /><applet load="1pyz" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1pyz, resolution 1.25Å" /> | caption="1pyz, resolution 1.25Å" /> | ||
'''CRYSTALLOGRAPHIC STRUCTURE OF MIMOCHROME IV'''<br /> | '''CRYSTALLOGRAPHIC STRUCTURE OF MIMOCHROME IV'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Protein design provides an attractive approach to test the essential | + | Protein design provides an attractive approach to test the essential features required for folding and function. Previously, we described the design and structural characterization in solution of mimochromes, a series of miniaturized metalloproteins, patterned after the F-helix of the hemoglobin beta-chain. Mimochromes consist of two medium-sized helical peptides, covalently linked to the deuteroporphyrin. CD and NMR characterization of the prototype, mimochrome I, revealed that the overall structure conforms well to the design. However, formation of Delta and Lambda diastereomers was observed. To overcome the problem of diastereomer formation, we re-designed mimochrome I, by engineering intramolecular, interchain interactions. The resulting model was mimochrome IV: the solution structural characterization showed the presence of the Lambda isomer as a unique form. To examine the extent to which the stereochemical stability and uniqueness of mimochrome IV was retained in the solid state, the crystal structure of Co(III)-mimochrome IV was solved by X-ray diffraction, and compared to the solution structure of the same derivative. Co(III)-mimochrome IV structures, both in solution and in the solid state, are characterized by the following common features: a bis-His axial coordination, a Lambda configuration around the metal ion, and a predominant helical conformation of the peptide chains. However, in the crystal structure, intrachain Glu1-Arg9 ion pairs are preferred over the designed, and experimentally found in solution, interchain interactions. This ion pairing switch may be related to strong packing interactions. |
==About this Structure== | ==About this Structure== | ||
| - | 1PYZ is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/ ] with CL, ACE, NH2 and DEU as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1PYZ is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/ ] with <scene name='pdbligand=CL:'>CL</scene>, <scene name='pdbligand=ACE:'>ACE</scene>, <scene name='pdbligand=NH2:'>NH2</scene> and <scene name='pdbligand=DEU:'>DEU</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1PYZ OCA]. |
==Reference== | ==Reference== | ||
Miniaturized heme proteins: crystal structure of Co(III)-mimochrome IV., Di Costanzo L, Geremia S, Randaccio L, Nastri F, Maglio O, Lombardi A, Pavone V, J Biol Inorg Chem. 2004 Dec;9(8):1017-27. Epub 2004 Nov 13. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=15551102 15551102] | Miniaturized heme proteins: crystal structure of Co(III)-mimochrome IV., Di Costanzo L, Geremia S, Randaccio L, Nastri F, Maglio O, Lombardi A, Pavone V, J Biol Inorg Chem. 2004 Dec;9(8):1017-27. Epub 2004 Nov 13. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=15551102 15551102] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
| - | [[Category: Costanzo, L | + | [[Category: Costanzo, L Di.]] |
[[Category: Geremia, S.]] | [[Category: Geremia, S.]] | ||
[[Category: Lombardi, A.]] | [[Category: Lombardi, A.]] | ||
| Line 26: | Line 26: | ||
[[Category: miniaturized metalloprotein]] | [[Category: miniaturized metalloprotein]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:34:07 2008'' |
Revision as of 12:34, 21 February 2008
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CRYSTALLOGRAPHIC STRUCTURE OF MIMOCHROME IV
Overview
Protein design provides an attractive approach to test the essential features required for folding and function. Previously, we described the design and structural characterization in solution of mimochromes, a series of miniaturized metalloproteins, patterned after the F-helix of the hemoglobin beta-chain. Mimochromes consist of two medium-sized helical peptides, covalently linked to the deuteroporphyrin. CD and NMR characterization of the prototype, mimochrome I, revealed that the overall structure conforms well to the design. However, formation of Delta and Lambda diastereomers was observed. To overcome the problem of diastereomer formation, we re-designed mimochrome I, by engineering intramolecular, interchain interactions. The resulting model was mimochrome IV: the solution structural characterization showed the presence of the Lambda isomer as a unique form. To examine the extent to which the stereochemical stability and uniqueness of mimochrome IV was retained in the solid state, the crystal structure of Co(III)-mimochrome IV was solved by X-ray diffraction, and compared to the solution structure of the same derivative. Co(III)-mimochrome IV structures, both in solution and in the solid state, are characterized by the following common features: a bis-His axial coordination, a Lambda configuration around the metal ion, and a predominant helical conformation of the peptide chains. However, in the crystal structure, intrachain Glu1-Arg9 ion pairs are preferred over the designed, and experimentally found in solution, interchain interactions. This ion pairing switch may be related to strong packing interactions.
About this Structure
1PYZ is a Protein complex structure of sequences from [1] with , , and as ligands. Full crystallographic information is available from OCA.
Reference
Miniaturized heme proteins: crystal structure of Co(III)-mimochrome IV., Di Costanzo L, Geremia S, Randaccio L, Nastri F, Maglio O, Lombardi A, Pavone V, J Biol Inorg Chem. 2004 Dec;9(8):1017-27. Epub 2004 Nov 13. PMID:15551102
Page seeded by OCA on Thu Feb 21 14:34:07 2008
