The Dinuclear Center of Cytochrome bo
3 from Escherichia coli |
| |
Authors: | Nicholas J Watmough Myles R Cheesman Clive S Butler Richard H Little Colin Greenwood Andrew J Thomson |
| |
Institution: | (1) Centre for Metalloprotein Spectroscopy and Biology, School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom;(2) Centre for Metalloprotein Spectroscopy and Biology, School of Chemical Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom |
| |
Abstract: | For the study of the dinuclear center of heme-copper oxidases cytochrome bo
3 from Escherichia coli offers several advantages over the extensively charactererized bovine cytochrome c oxidase. The availability of strains with enhanced levels of expression allows purification of the significant amounts of enzyme required for detailed spectroscopic studies. Cytochrome bo
3 is readily prepared as the fast form, with a homogeneous dinuclear center which gives rise to characteristic broad EPR signals not seen in CcO. The absence of CuA and the incorporation of protohemes allows for a detailed interpretation of the MCD spectra arising from the dinuclear center heme o
3. Careful analysis allows us to distinguish between small molecules that bind to heme o
3, those which are ligands of CuB, and those which react to yield higher oxidation states of heme o
3. Here we review results from our studies of the reactions of fast cytochrome bo
3 with formate, fluoride, chloride, azide, cyanide, NO, and H2O2. |
| |
Keywords: | Escherichia coli Quinol oxidase cytochrome bo3 cytochrome c oxidase nitric oxide reductase EPR spectroscopy MCD spectroscopy oxyferryl heme |
本文献已被 SpringerLink 等数据库收录! |
|