1foc
From Proteopedia
(New page: 200px<br /><applet load="1foc" size="450" color="white" frame="true" align="right" spinBox="true" caption="1foc, resolution 3.0Å" /> '''Cytochrome C557: impr...) |
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| - | [[Image:1foc.gif|left|200px]]<br /><applet load="1foc" size=" | + | [[Image:1foc.gif|left|200px]]<br /><applet load="1foc" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1foc, resolution 3.0Å" /> | caption="1foc, resolution 3.0Å" /> | ||
'''Cytochrome C557: improperly folded thermus thermophilus C552'''<br /> | '''Cytochrome C557: improperly folded thermus thermophilus C552'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Cytochrome rC(557) is an improperly matured, dimeric cytochrome c obtained | + | Cytochrome rC(557) is an improperly matured, dimeric cytochrome c obtained from expression of the "signal peptide-lacking" Thermus thermophilus cycA gene in the cytoplasm of Escherichia coli. It is characterized by its Q(00) (or alpha-) optical absorption band at 557 nm in the reduced form (Keightley, J. A., Sanders, D., Todaro, T. R., Pastuszyn, A., and Fee, J. A. (1998) J. Biol. Chem. 273, 12006-12016). We report results of a broad ranging, biochemical and spectral characterization of this protein that reveals the presence of a free vinyl group on the porphyrin and a disulfide bond between the protomers and supports His-Met ligation in both valence states of the iron. A 3-A resolution x-ray structure shows that, in comparison with the native protein, the heme moiety is rotated 180 degrees about its alpha,gamma-axis; cysteine 14 has formed a thioether bond with the 2-vinyl of pyrrole ring I instead of the 4-vinyl of pyrrole ring II, as occurs in the native protein; and a cysteine 11 from each protomer has formed an intermolecular disulfide bond. Numerous, minor perturbations exist within the structure of rC(557) in comparison with that of native protein, which result from heme inversion and protein-protein interactions across the dimer interface. The unusual spectral properties of rC(557) are rationalized in terms of this structure. |
==About this Structure== | ==About this Structure== | ||
| - | 1FOC is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermus_thermophilus Thermus thermophilus] with HEM as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1FOC is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermus_thermophilus Thermus thermophilus] with <scene name='pdbligand=HEM:'>HEM</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1FOC OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Thermus thermophilus]] | [[Category: Thermus thermophilus]] | ||
| - | [[Category: Bren, K | + | [[Category: Bren, K L.]] |
| - | [[Category: Fee, J | + | [[Category: Fee, J A.]] |
| - | [[Category: McRee, D | + | [[Category: McRee, D E.]] |
| - | [[Category: Williams, P | + | [[Category: Williams, P A.]] |
[[Category: HEM]] | [[Category: HEM]] | ||
[[Category: cytochrome c]] | [[Category: cytochrome c]] | ||
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[[Category: thermus thermophilus]] | [[Category: thermus thermophilus]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:40:50 2008'' |
Revision as of 10:40, 21 February 2008
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Cytochrome C557: improperly folded thermus thermophilus C552
Overview
Cytochrome rC(557) is an improperly matured, dimeric cytochrome c obtained from expression of the "signal peptide-lacking" Thermus thermophilus cycA gene in the cytoplasm of Escherichia coli. It is characterized by its Q(00) (or alpha-) optical absorption band at 557 nm in the reduced form (Keightley, J. A., Sanders, D., Todaro, T. R., Pastuszyn, A., and Fee, J. A. (1998) J. Biol. Chem. 273, 12006-12016). We report results of a broad ranging, biochemical and spectral characterization of this protein that reveals the presence of a free vinyl group on the porphyrin and a disulfide bond between the protomers and supports His-Met ligation in both valence states of the iron. A 3-A resolution x-ray structure shows that, in comparison with the native protein, the heme moiety is rotated 180 degrees about its alpha,gamma-axis; cysteine 14 has formed a thioether bond with the 2-vinyl of pyrrole ring I instead of the 4-vinyl of pyrrole ring II, as occurs in the native protein; and a cysteine 11 from each protomer has formed an intermolecular disulfide bond. Numerous, minor perturbations exist within the structure of rC(557) in comparison with that of native protein, which result from heme inversion and protein-protein interactions across the dimer interface. The unusual spectral properties of rC(557) are rationalized in terms of this structure.
About this Structure
1FOC is a Single protein structure of sequence from Thermus thermophilus with as ligand. Full crystallographic information is available from OCA.
Reference
Recombinant cytochrome rC557 obtained from Escherichia coli cells expressing a truncated Thermus thermophilus cycA gene. Heme inversion in an improperly matured protein., McRee DE, Williams PA, Sridhar V, Pastuszyn A, Bren KL, Patel KM, Chen Y, Todaro TR, Sanders D, Luna E, Fee JA, J Biol Chem. 2001 Mar 2;276(9):6537-44. Epub 2000 Nov 7. PMID:11069913
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