Solution structure and dynamics of the functional domain of Paracoccus denitrificans cytochrome c(552) in both redox states.Reincke, B., Perez, C., Pristovsek, P., Lucke, C., Ludwig, C., Lohr, F., Rogov, V.V., Ludwig, B., Ruterjans, H.
(2001) Biochemistry 40: 12312-12320
- PubMed: 11591150
- Primary Citation of Related Structures:  1I6E
- PubMed Abstract:
- Heterologous Expression of Soluble Fragments of Cytochrome C552 Acting as Electron Donor to the Paracoccus Denitrificans Cytochrome C Oxidase
Reincke, B.,Thoeny-Meyer, L.,Dannehl, C.,Odenwald, A.,Aidim, M.,Witt, H.,Rueterjans, H.,Ludwig, B.
(1999) Biochim.Biophys.Acta 1441: 114
- Structure of the Soluble Domain of Cytochrome C552 from Paracoccus Denitrificans in the Oxidized and Reduced States
Harrenga, A.,Reincke, B.,Rueterjans, H.,Ludwig, B.,Michel, H.
(2000) J.Mol.Biol. 295: 667
- Solution Structure of the Functional Domain of Paracoccus Denitrificans Cytochrome C552 in the Reduced State
Pristovsek, P.,Luecke, C.,Reincke, B.,Ludwig, B.,Rueterjans, H.
(2000) Eur.J.Biochem. 267: 4205
A soluble and fully functional 10.5 kDa fragment of the 18.2 kDa membrane-bound cytochrome c(552) from Paracoccus denitrificans has been heterologously expressed and (13)C/(15)N-labeled to study the structural features of this protein in both redox s ...
A soluble and fully functional 10.5 kDa fragment of the 18.2 kDa membrane-bound cytochrome c(552) from Paracoccus denitrificans has been heterologously expressed and (13)C/(15)N-labeled to study the structural features of this protein in both redox states. Well-resolved solution structures of both the reduced and oxidized states have been determined using high-resolution heteronuclear NMR. The overall protein topology consists of two long terminal helices and three shorter helices surrounding the heme moiety. No significant redox-induced structural differences have been observed. (15)N relaxation rates and heteronuclear NOE values were determined at 500 and 600 MHz. Several residues located around the heme moiety display increased backbone mobility in both oxidation states, while helices I, III, and V as well as the two concatenated beta-turns between Leu30 and Arg36 apparently form a less flexible domain within the protein structure. Major redox-state-dependent differences of the internal backbone mobility on the picosecond-nanosecond time scale were not evident. Hydrogen exchange experiments demonstrated that the slow-exchanging amide proton resonances mainly belong to the helices and beta-turns, corresponding to the regions with high order parameters in the dynamics data. Despite this correlation, the backbone amide protons of the oxidized cytochrome c(552) exchange considerably faster with the solvent compared to the reduced protein. Using both differential scanning calorimetry as well as temperature-dependent NMR spectroscopy, a significant difference in the thermostabilities of the two redox states has been observed, with transition temperatures of 349.9 K (76.8 degrees C) for reduced and 307.5 K (34.4 degrees C) for oxidized cytochrome c(552). These results suggest a clearly distinct backbone stability between the two oxidation states.
Institute of Biophysical Chemistry,J.W. Goethe-University of Frankfurt, Marie-Curie-Strabetae 9, 60439 Frankfurt a.M., Germany.