Characterization of the pH-dependent resonance Raman transitions of archaeal and bacterial Rieske [2Fe-2S] proteins.
نویسندگان
چکیده
The pH-dependent resonance Raman (RR) spectral changes of the cytochrome bc1-associated, high-potential Rieske proteins have frequently been invoked to explain the redox-linked ionization behavior. We report herein RR spectral data of archaeal and bacterial Rieske proteins that directly demonstrate the pH-dependent changes near and above pKa,ox2, but not around pKa,ox1, of the visible circular dichroism (CD) transitions. The RR spectral changes are attributed to modification of the immediate [2Fe-2S] cluster environment due to deprotonation of some exchangeable amide groups in the polypeptide backbone, rather than previously assumed simple changes of the Fe-Nimid stretching vibrations.
منابع مشابه
Resonance Raman characterization of archaeal and bacterial Rieske protein variants with modified hydrogen bond network around the [2Fe-2S] center.
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عنوان ژورنال:
- Journal of the American Chemical Society
دوره 126 15 شماره
صفحات -
تاریخ انتشار 2004