論文 - 詳細
| RRC ID | 4953 |
|---|---|
| 著者 | Bekker M, de Vries S, Ter Beek A, Hellingwerf KJ, de Mattos MJ. |
| タイトル | Respiration of Escherichia coli can be fully uncoupled via the nonelectrogenic terminal cytochrome bd-II oxidase. |
| ジャーナル | J Bacteriol |
| Abstract |
The respiratory chain of Escherichia coli is usually considered a device to conserve energy via the generation of a proton motive force, which subsequently may drive ATP synthesis by the ATP synthetase. It is known that in this system a fixed amount of ATP per oxygen molecule reduced (P/O ratio) is not synthesized due to alternative NADH dehydrogenases and terminal oxidases with different proton pumping stoichiometries. Here we show that P/O ratios can vary much more than previously thought. First, we show that in wild-type E. coli cytochrome bo, cytochrome bd-I, and cytochrome bd-II are the major terminal oxidases; deletion of all of the genes encoding these enzymes results in a fermentative phenotype in the presence of oxygen. Second, we provide evidence that the electron flux through cytochrome bd-II oxidase is significant but does not contribute to the generation of a proton motive force. The kinetics support the view that this system is as an energy-independent system gives the cell metabolic flexibility by uncoupling catabolism from ATP synthesis under non-steady-state conditions. The nonelectrogenic nature of cytochrome bd-II oxidase implies that the respiratory chain can function in a fully uncoupled mode such that ATP synthesis occurs solely by substrate level phosphorylation. As a consequence, the yield with a carbon and energy source can vary five- to sevenfold depending on the electron flux distribution in the respiratory chain. A full understanding and control of this distribution open new avenues for optimization of biotechnological processes. |
| 巻・号 | 191(17) |
| ページ | 5510-7 |
| 公開日 | 2009-9-1 |
| DOI | 10.1128/JB.00562-09 |
| PII | JB.00562-09 |
| PMID | 19542282 |
| PMC | PMC2725625 |
| MeSH | Adenosine Triphosphate / biosynthesis* Cytochrome b Group / genetics Cytochrome b Group / metabolism Cytochromes / genetics Cytochromes / metabolism* Electron Transport Chain Complex Proteins / genetics Electron Transport Chain Complex Proteins / metabolism* Escherichia coli / genetics Escherichia coli / metabolism* Escherichia coli Proteins / genetics Escherichia coli Proteins / metabolism* Fermentation Gene Deletion Oxidoreductases / genetics Oxidoreductases / metabolism* Oxygen Consumption* |
| IF | 3.006 |
| 引用数 | 63 |
| WOS 分野 | MICROBIOLOGY |
| オルトメトリクス指標 |
オルトメトリクス指標項目
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| 最多言及媒体 | Patent(IFI CLAIMS) |
| 各媒体での言及数の合計 | 9 |
| 過去6か月間でのオルトメトリクス指標の変動値 | 0.0 |
| リソース情報 | |
| 原核生物(大腸菌) | ME7986(MG1655) ME9062(BW25113) |