ArticleProceedings of the National Academy of Sciences of the United States of America2009
Menaquinone as pool quinone in a purple bacterium.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 56 papers.
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56 citing papers in PubMed, 127 citations in OpenAlex.
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- Oxygen reductase origin followed the great oxidation event and terminated the Lomagundi excursion.Biochimica et biophysica acta. Bioenergetics · 2026Article
- Mycobacterial respiratory chain enzymes and growth are inhibited by decylubiquinone.Communications biology · 2025Article
- Naphthoquinone preferentially pairs with non-proton-pumping NADH dehydrogenase for respiratory electron transport.PLoS genetics · 2025Article
- A novel quinone biosynthetic pathway illuminates the evolution of aerobic metabolism.Proceedings of the National Academy of Sciences of the United States of America · 2025Article
- A Native LH1-RC-HiPIP Supercomplex from an Extremophilic Phototroph.Communications biology · 2025Article
- Dynamic quinone repertoire accompanied the diversification of energy metabolism in Pseudomonadota.The ISME journal · 2025Article
- Cryo-EM structure of HQNO-bound alternative complex III from the anoxygenic phototrophic bacterium Chloroflexus aurantiacus.The Plant cell · 2024Article
- Diverse non-canonical electron bifurcating [FeFe]-hydrogenases of separate evolutionary origins inmSystems · 2024Article
- Identification of commensal gut microbiota signatures as predictors of clinical severity and disease progression in multiple sclerosis.Scientific reports · 2024Article
- A cytochrome cPlant communications · 2024Article
- Diversification of Ubiquinone Biosynthesis via Gene Duplications, Transfers, Losses, and Parallel Evolution.Molecular biology and evolution · 2023Article
- Biosynthesis, Deficiency, and Supplementation of Coenzyme Q.Antioxidants (Basel, Switzerland) · 2023Review
- High-level in vitro resistance to gentamicin acquired in a stepwise manner in Neisseria gonorrhoeae.The Journal of antimicrobial chemotherapy · 2023Article
- Cellular Stress-Induced Metabolites inJournal of natural products · 2022Article
- Chemistry of Lipoquinones: Properties, Synthesis, and Membrane Location of Ubiquinones, Plastoquinones, and Menaquinones.International journal of molecular sciences · 2022Review
- (Meta)Genomic Analysis Reveals Diverse Energy Conservation Strategies Employed by Globally DistributedmSystems · 2022Article
- Quinone binding sites of cyt bc complexes analysed by X-ray crystallography and cryogenic electron microscopy.Biochemical Society transactions · 2022Review
- The missing enzymatic link in syntrophic methane formation from fatty acids.Proceedings of the National Academy of Sciences of the United States of America · 2021Article
- Location and Conformational Ensemble of Menaquinone and Menaquinol, and Protein-Lipid Modulations in Archaeal Membranes.The journal of physical chemistry. B · 2021Article
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Authors and funding
7 authors at 4 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Purple bacteria have thus far been considered to operate light-driven cyclic electron transfer chains containing ubiquinone (UQ) as liposoluble electron and proton carrier. We show that in the purple gamma-proteobacterium Halorhodospira halophila, menaquinone-8 (MK-8) is the dominant quinone component and that it operates in the Q(B)-site of the photosynthetic reaction center (RC). The redox potentials of the photooxidized pigment in the RC and of the Rieske center of the bc(1) complex are significantly lower (E(m) = +270 mV and +110 mV, respectively) than those determined in other purple bacteria but resemble those determined for species containing MK as pool quinone. These results demonstrate that the photosynthetic cycle in H. halophila is based on MK and not on UQ. This finding together with the unusual organization of genes coding for the bc(1) complex in H. halophila suggests a specific scenario for the evolutionary transition of bioenergetic chains from the low-potential menaquinones to higher-potential UQ in the proteobacterial phylum, most probably induced by rising levels of dioxygen 2.5 billion years ago. This transition appears to necessarily proceed through bioenergetic ambivalence of the respective organisms, that is, to work both on MK- and on UQ-pools. The establishment of the corresponding low- and high-potential chains was accompanied by duplication and redox optimization of the bc(1) complex or at least of its crucial subunit oxidizing quinols from the pool, the Rieske protein. Evolutionary driving forces rationalizing the empirically observed redox tuning of the chain to the quinone pool are discussed.
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