A Self‐Assembled Respiratory Chain that Catalyzes NADH Oxidation by Ubiquinone‐10 Cycling between Complex I and the Alternative Oxidase
Complex I is a crucial respiratory enzyme that conserves the energy from NADH oxidation by ubiquinone‐10 (Q10) in proton transport across a membrane. Studies of its energy transduction mechanism are hindered by the extreme hydrophobicity of Q10, and they have so far relied on native membranes with m...
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| Format: | Online |
| Language: | English |
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WILEY‐VCH Verlag
2015
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| Online Access: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4954055/ |
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pubmed-4954055 |
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oai_dc |
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pubmed-49540552016-07-29 A Self‐Assembled Respiratory Chain that Catalyzes NADH Oxidation by Ubiquinone‐10 Cycling between Complex I and the Alternative Oxidase Jones, Andrew J. Y. Blaza, James N. Bridges, Hannah R. May, Benjamin Moore, Anthony L. Hirst, Judy Communications Complex I is a crucial respiratory enzyme that conserves the energy from NADH oxidation by ubiquinone‐10 (Q10) in proton transport across a membrane. Studies of its energy transduction mechanism are hindered by the extreme hydrophobicity of Q10, and they have so far relied on native membranes with many components or on hydrophilic Q10 analogues that partition into membranes and undergo side reactions. Herein, we present a self‐assembled system without these limitations: proteoliposomes containing mammalian complex I, Q10, and a quinol oxidase (the alternative oxidase, AOX) to recycle Q10H2 to Q10. AOX is present in excess, so complex I is completely rate determining and the Q10 pool is kept oxidized under steady‐state catalysis. The system was used to measure a fully‐defined K M value for Q10. The strategy is suitable for any enzyme with a hydrophobic quinone/quinol substrate, and could be used to characterize hydrophobic inhibitors with potential applications as pharmaceuticals, pesticides, or fungicides. WILEY‐VCH Verlag 2015-11-23 2016-01-11 /pmc/articles/PMC4954055/ /pubmed/26592861 http://dx.doi.org/10.1002/anie.201507332 Text en © 2015 The Authors. Published by Wiley‐VCH Verlag GmbH & Co. KGaA. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. Open access. |
| repository_type |
Open Access Journal |
| institution_category |
Foreign Institution |
| institution |
US National Center for Biotechnology Information |
| building |
NCBI PubMed |
| collection |
Online Access |
| language |
English |
| format |
Online |
| author |
Jones, Andrew J. Y. Blaza, James N. Bridges, Hannah R. May, Benjamin Moore, Anthony L. Hirst, Judy |
| spellingShingle |
Jones, Andrew J. Y. Blaza, James N. Bridges, Hannah R. May, Benjamin Moore, Anthony L. Hirst, Judy A Self‐Assembled Respiratory Chain that Catalyzes NADH Oxidation by Ubiquinone‐10 Cycling between Complex I and the Alternative Oxidase |
| author_facet |
Jones, Andrew J. Y. Blaza, James N. Bridges, Hannah R. May, Benjamin Moore, Anthony L. Hirst, Judy |
| author_sort |
Jones, Andrew J. Y. |
| title |
A Self‐Assembled Respiratory Chain that Catalyzes NADH Oxidation by Ubiquinone‐10 Cycling between Complex I and the Alternative Oxidase |
| title_short |
A Self‐Assembled Respiratory Chain that Catalyzes NADH Oxidation by Ubiquinone‐10 Cycling between Complex I and the Alternative Oxidase |
| title_full |
A Self‐Assembled Respiratory Chain that Catalyzes NADH Oxidation by Ubiquinone‐10 Cycling between Complex I and the Alternative Oxidase |
| title_fullStr |
A Self‐Assembled Respiratory Chain that Catalyzes NADH Oxidation by Ubiquinone‐10 Cycling between Complex I and the Alternative Oxidase |
| title_full_unstemmed |
A Self‐Assembled Respiratory Chain that Catalyzes NADH Oxidation by Ubiquinone‐10 Cycling between Complex I and the Alternative Oxidase |
| title_sort |
self‐assembled respiratory chain that catalyzes nadh oxidation by ubiquinone‐10 cycling between complex i and the alternative oxidase |
| description |
Complex I is a crucial respiratory enzyme that conserves the energy from NADH oxidation by ubiquinone‐10 (Q10) in proton transport across a membrane. Studies of its energy transduction mechanism are hindered by the extreme hydrophobicity of Q10, and they have so far relied on native membranes with many components or on hydrophilic Q10 analogues that partition into membranes and undergo side reactions. Herein, we present a self‐assembled system without these limitations: proteoliposomes containing mammalian complex I, Q10, and a quinol oxidase (the alternative oxidase, AOX) to recycle Q10H2 to Q10. AOX is present in excess, so complex I is completely rate determining and the Q10 pool is kept oxidized under steady‐state catalysis. The system was used to measure a fully‐defined K
M value for Q10. The strategy is suitable for any enzyme with a hydrophobic quinone/quinol substrate, and could be used to characterize hydrophobic inhibitors with potential applications as pharmaceuticals, pesticides, or fungicides. |
| publisher |
WILEY‐VCH Verlag |
| publishDate |
2015 |
| url |
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4954055/ |
| _version_ |
1613612355309010944 |