Λεπτομέρειες βιβλιογραφικής εγγραφής
| Τίτλος: |
Quinol-cytochrome c Oxidoreductase and Cytochrome c 4 Mediate Electron Transfer during Selenate Respiration in Thauera selenatis |
| Συγγραφείς: |
Lowe EC, Bydder S, Hartshorne RS, Tape HLU, Dridge EJ, Debieux CM, Paszkiewicz K, Singleton I, Lewis RJ, Santini JM, Richardson DJ, Butler CS |
| Πηγή: |
Journal of Biological Chemistry, 11-06-2010 |
| Στοιχεία εκδότη: |
American Society for Biochemistry and Molecular Biology, Inc. |
| Έτος έκδοσης: |
2010 |
| Συλλογή: |
Newcastle University Library ePrints Service |
| Περιγραφή: |
Selenatereductase(SER) from Thaueraselenatis 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 (similar to 24 and similar to 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. |
| Τύπος εγγράφου: |
article in journal/newspaper |
| Γλώσσα: |
unknown |
| Relation: |
https://eprints.ncl.ac.uk/156154 |
| Διαθεσιμότητα: |
https://eprints.ncl.ac.uk/156154 |
| Αριθμός Καταχώρησης: |
edsbas.49BD160C |
| Βάση Δεδομένων: |
BASE |