1f22
From Proteopedia
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A PROTON-NMR INVESTIGATION OF THE FULLY REDUCED CYTOCHROME C7 FROM DESULFUROMONAS ACETOXIDANS. COMPARISON BETWEEN THE REDUCED AND THE OXIDIZED FORMS.
Overview
The solution structure via 1H NMR of the fully reduced form of cytochrome, c7 has been obtained. The protein sample was kept reduced by addition of, catalytic amounts of Desulfovibrio gigas iron hydrogenase in H2 atmosphere, after it had been checked that the presence of the hydrogenase did not, affect the NMR spectrum. A final family of 35 conformers with rmsd values, with respect to the mean structure of 8.7 +/- 1.5 nm and 12.4 +/- 1.3 nm, for the backbone and heavy atoms, respectively, was obtained. A highly, disordered loop involving residues 54-61 is present. If this loop is, ignored, the rmsd values are 6.2 +/- 1.1 nm and 10.2 +/- 1.0 nm for the, backbone and heavy atoms, respectively, which represent a reasonable, resolution. The structure was analyzed and compared with the already, available structure of the fully oxidized protein. Within the, indetermination of the two solution structures, the result for the two, redox forms is quite similar, confirming the special structural features, of the three-heme cluster. A useful comparison can be made with the, available crystal structures of cytochromes c3, which appear to be highly, homologous except for the presence of a further heme. Finally, an analysis, of the factors affecting the reduction potentials of the heme irons was, performed, revealing the importance of net charges in differentiating the, reduction potential when the other parameters are kept constant.
About this Structure
1F22 is a Single protein structure of sequence from Desulfuromonas acetoxidans with HEC as ligand. Full crystallographic information is available from OCA.
Reference
A proton-NMR investigation of the fully reduced cytochrome c7 from Desulfuromonas acetoxidans. Comparison between the reduced and the oxidized forms., Assfalg M, Banci L, Bertini I, Bruschi M, Giudici-Orticoni MT, Turano P, Eur J Biochem. 1999 Dec;266(2):634-43. PMID:10561607
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