Autor: |
Oda K; Chemistry Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA., Ogura T, Appelman EH, Yoshikawa S |
Jazyk: |
angličtina |
Zdroj: |
FEBS letters [FEBS Lett] 2004 Jul 16; Vol. 570 (1-3), pp. 161-5. |
DOI: |
10.1016/j.febslet.2004.06.036 |
Abstrakt: |
Aeration of a two-electron reduced cytochrome c oxidase provides a species with two Raman bands at 804 and 356 cm(-1), identifying it as the second intermediate following the O2-bound species in the enzymatic O2 reduction process. It degrades directly to the fully oxidized form with a half-life time of 70 min at pH 8.0. The stability suggests an effective insulation for the active site in an extremely high oxidation state (Fe4+ with one oxidative equivalent nearby) against spontaneous electron leaks, which would dissipate proton motive force. The formation and degradation of the second intermediate are pH-dependent. |
Databáze: |
MEDLINE |
Externí odkaz: |
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