dc.contributor.author | Lowe, EC | |
dc.contributor.author | Bydder, S | |
dc.contributor.author | Hartshorne, RS | |
dc.contributor.author | Tape, HL | |
dc.contributor.author | Dridge, Elizabeth J. | |
dc.contributor.author | Debieux, Charles M. | |
dc.contributor.author | Paszkiewicz, K | |
dc.contributor.author | Singleton, I | |
dc.contributor.author | Lewis, RJ | |
dc.contributor.author | Santini, JM | |
dc.contributor.author | Richardson, DJ | |
dc.contributor.author | Butler, Clive S | |
dc.date.accessioned | 2013-05-08T14:32:43Z | |
dc.date.issued | 2010-06-11 | |
dc.description.abstract | Selenate reductase (SER) from Thauera selenatis is a periplasmic enzyme that has been classified as a type II molybdoenzyme. The enzyme comprises three subunits SerABC, where SerC is an unusual b-heme cytochrome. In the present work the spectropotentiometric characterization of the SerC component and the identification of redox partners to SER are reported. The mid-point redox potential of the b-heme was determined by optical titration (E(m) + 234 +/- 10 mV). A profile of periplasmic c-type cytochromes expressed in T. selenatis under selenate respiring conditions was undertaken. Two c-type cytochromes were purified ( approximately 24 and approximately 6 kDa), and the 24-kDa protein (cytc-Ts4) was shown to donate electrons to SerABC in vitro. Protein sequence of cytc-Ts4 was obtained by N-terminal sequencing and liquid chromatography-tandem mass spectrometry analysis, and based upon sequence similarities, was assigned as a member of cytochrome c(4) family. Redox potentiometry, combined with UV-visible spectroscopy, showed that cytc-Ts4 is a diheme cytochrome with a redox potential of +282 +/- 10 mV, and both hemes are predicted to have His-Met ligation. To identify the membrane-bound electron donors to cytc-Ts4, growth of T. selenatis in the presence of respiratory inhibitors was monitored. The specific quinol-cytochrome c oxidoreductase (QCR) inhibitors myxothiazol and antimycin A partially inhibited selenate respiration, demonstrating that some electron flux is via the QCR. Electron transfer via a QCR and a diheme cytochrome c(4) is a novel route for a member of the DMSO reductase family of molybdoenzymes. | en_GB |
dc.identifier.citation | Vol. 285, Issue 24, pp. 18433 - 18442 | en_GB |
dc.identifier.doi | 10.1074/jbc.M110.115873 | |
dc.identifier.uri | http://hdl.handle.net/10871/9201 | |
dc.publisher | American Society for Biochemistry | en_GB |
dc.relation.url | http://www.jbc.org/content/285/24/18433.long | en_GB |
dc.subject | Antimycin A | en_GB |
dc.subject | Cytochrome c Group | en_GB |
dc.subject | Cytochromes | en_GB |
dc.subject | Electron Transport | en_GB |
dc.subject | Electron Transport Complex IV | en_GB |
dc.subject | Electrons | en_GB |
dc.subject | Hydroquinones | en_GB |
dc.subject | Methacrylates | en_GB |
dc.subject | Models, Biological | en_GB |
dc.subject | Models, Chemical | en_GB |
dc.subject | Models, Molecular | en_GB |
dc.subject | Oxidation-Reduction | en_GB |
dc.subject | Selenium | en_GB |
dc.subject | Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization | en_GB |
dc.subject | Thauera | en_GB |
dc.subject | Thiazoles | en_GB |
dc.title | Quinol-cytochrome c oxidoreductase and cytochrome c4 mediate electron transfer during selenate respiration in Thauera selenatis | en_GB |
dc.type | Article | en_GB |
dc.date.available | 2013-05-08T14:32:43Z | |
dc.identifier.issn | 0021-9258 | |
exeter.place-of-publication | United States | |
dc.description | This research was originally published in Journal of Biological Chemistry. E Lowe et al. Quinol-cytochrome c oxidoreductase and cytochrome c4 mediate electron transfer during selenate respiration in Thauera selenatis. Journal of Biological Chemistry. 2010. Vol:pp 18433-42. © the American Society for Biochemistry and Molecular Biology | en_GB |
dc.identifier.journal | Journal of Biological Chemistry | en_GB |