1lm2
From Proteopedia
(New page: 200px<br /><applet load="1lm2" size="450" color="white" frame="true" align="right" spinBox="true" caption="1lm2" /> '''NMR structural characterization of the reduc...) |
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| - | [[Image:1lm2.jpg|left|200px]]<br /><applet load="1lm2" size=" | + | [[Image:1lm2.jpg|left|200px]]<br /><applet load="1lm2" size="350" color="white" frame="true" align="right" spinBox="true" |
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'''NMR structural characterization of the reduction of chromium(VI) to chromium(III) by cytochrome c7'''<br /> | '''NMR structural characterization of the reduction of chromium(VI) to chromium(III) by cytochrome c7'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The redox reaction between CrO(4)(2-) and the fully reduced three-heme | + | The redox reaction between CrO(4)(2-) and the fully reduced three-heme cytochrome c(7) from Desulfuromonas acetoxidans to give chromium(III) and the fully oxidized protein has been followed by NMR spectroscopy. The hyperfine coupling between the oxidized protein protons and chromium(III), which remains bound to the protein, gives rise to line-broadening effects on the NMR resonances that can be transformed into proton-metal distance restraints. Structure calculations based on these unconventional constraints allowed us to demonstrate that chromium(III) binds at a unique site and to locate it on the protein surface. The metal ion is located 7.9 +/- 0.4 A from the iron of heme IV, 16.3 +/- 0.7 A from the iron of heme III, and 22.5 +/- 0.5 A from the iron of heme I. Shift changes caused by the presence of unreactive MoO(4)(2-), a CrO(4)(2-) analogue, indicate the involvement of the same protein area in the anion binding. The titration of the oxidation of cytochrome c(7) shows a detailed mechanism of action. The presence of a specific binding site supports the hypothesis of the biological role of this cytochrome as a metal reductase. |
==About this Structure== | ==About this Structure== | ||
| - | 1LM2 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Desulfuromonas_acetoxidans Desulfuromonas acetoxidans] with CR and HEC as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1LM2 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Desulfuromonas_acetoxidans Desulfuromonas acetoxidans] with <scene name='pdbligand=CR:'>CR</scene> and <scene name='pdbligand=HEC:'>HEC</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1LM2 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: nmr]] | [[Category: nmr]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:46:12 2008'' |
Revision as of 11:46, 21 February 2008
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NMR structural characterization of the reduction of chromium(VI) to chromium(III) by cytochrome c7
Overview
The redox reaction between CrO(4)(2-) and the fully reduced three-heme cytochrome c(7) from Desulfuromonas acetoxidans to give chromium(III) and the fully oxidized protein has been followed by NMR spectroscopy. The hyperfine coupling between the oxidized protein protons and chromium(III), which remains bound to the protein, gives rise to line-broadening effects on the NMR resonances that can be transformed into proton-metal distance restraints. Structure calculations based on these unconventional constraints allowed us to demonstrate that chromium(III) binds at a unique site and to locate it on the protein surface. The metal ion is located 7.9 +/- 0.4 A from the iron of heme IV, 16.3 +/- 0.7 A from the iron of heme III, and 22.5 +/- 0.5 A from the iron of heme I. Shift changes caused by the presence of unreactive MoO(4)(2-), a CrO(4)(2-) analogue, indicate the involvement of the same protein area in the anion binding. The titration of the oxidation of cytochrome c(7) shows a detailed mechanism of action. The presence of a specific binding site supports the hypothesis of the biological role of this cytochrome as a metal reductase.
About this Structure
1LM2 is a Single protein structure of sequence from Desulfuromonas acetoxidans with and as ligands. Full crystallographic information is available from OCA.
Reference
The metal reductase activity of some multiheme cytochromes c: NMR structural characterization of the reduction of chromium(VI) to chromium(III) by cytochrome c(7)., Assfalg M, Bertini I, Bruschi M, Michel C, Turano P, Proc Natl Acad Sci U S A. 2002 Jul 23;99(15):9750-4. Epub 2002 Jul 15. PMID:12119407
Page seeded by OCA on Thu Feb 21 13:46:12 2008
Categories: Desulfuromonas acetoxidans | Single protein | Assfalg, M. | Bertini, I. | Bruschi, M. | Michel, C. | Turano, P. | CR | HEC | Chromium | Cytochrome c7 | Nmr
