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PloS One 2022Safranine O is widely used in the bioenergetics community as an indicator dye to determine membrane potentials and as an electron transfer mediator in potentiometric...
Safranine O is widely used in the bioenergetics community as an indicator dye to determine membrane potentials and as an electron transfer mediator in potentiometric titrations. Here we show that two different commercial preparations of Safranine O contain less than sixty percent by weight of the title compound, with the rest primarily consisting of two closely related safranine isomers. All three major isomer components were isolated using reverse phase HPLC and their structures determined using mass spectrometry and two-dimensional NMR. These Safranines have two-electron midpoint potentials ranging from -272 to -315 mV vs. SHE. We have also investigated the absorption and fluorescence spectra of the compounds and found that they display distinct spectral and photophysical properties. While this mixture may aid in Safranine O's utility as a mediator compound, membrane potential measurements must take this range of dye potentials into account.
Topics: Electron Transport; Oxidation-Reduction; Phenazines; Spectrometry, Fluorescence
PubMed: 35749430
DOI: 10.1371/journal.pone.0265105 -
Journal of the American Chemical Society Apr 2023We report the total synthesis of the furanobutenolide-derived diterpenoid (+)-ineleganolide. The synthetic approach relies on a convergent strategy based on the coupling...
We report the total synthesis of the furanobutenolide-derived diterpenoid (+)-ineleganolide. The synthetic approach relies on a convergent strategy based on the coupling of two enantioenriched fragments, which are derived from (-)-linalool and (+)-norcarvone, respectively. A high-yielding, one-step Michael addition and aldol cascade furnishes a pentacyclic framework as a single diastereomer, thereby overcoming previous challenges in controlling stereochemistry. The endgame features an O-facilitated C-H oxidation and a samarium diiodide-induced semipinacol rearrangement to furnish the highly rigid central seven-membered ring.
Topics: Cyclization; Diterpenes; Oxidation-Reduction
PubMed: 36989438
DOI: 10.1021/jacs.3c02142 -
Oxidative Medicine and Cellular... 2019
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Oxidative Medicine and Cellular... 2020Mitochondria are the main organelles that produce adenosine 5'-triphosphate (ATP) and reactive oxygen species (ROS) in eukaryotic cells and meanwhile susceptible to... (Review)
Review
Mitochondria are the main organelles that produce adenosine 5'-triphosphate (ATP) and reactive oxygen species (ROS) in eukaryotic cells and meanwhile susceptible to oxidative damage. The irreversible oxidative damage in mitochondria has been implicated in various human diseases. Increasing evidence indicates the therapeutic potential of mitochondria-targeted antioxidants (MTAs) for oxidative damage-associated diseases. In this article, we introduce the advantageous properties of MTAs compared with the conventional (nontargeted) ones, review different mitochondria-targeted delivery systems and antioxidants, and summarize their experimental results for various disease treatments in different animal models and clinical trials. The combined evidence demonstrates that mitochondrial redox homeostasis is a potential target for disease treatment. Meanwhile, the limitations and prospects for exploiting MTAs are discussed, which might pave ways for further trial design and drug development.
Topics: Animals; Antioxidants; Drug Delivery Systems; Humans; Mitochondria; Oxidation-Reduction
PubMed: 33354280
DOI: 10.1155/2020/8837893 -
Science Advances Feb 2023Genomic records of genetic recombination and mutation rates indicate that freshwater ammonia-oxidizing archaea have evolved through paleoclimate and geohydrological... (Review)
Review
Genomic records of genetic recombination and mutation rates indicate that freshwater ammonia-oxidizing archaea have evolved through paleoclimate and geohydrological history.
Topics: Oxidation-Reduction; Archaea; Fresh Water; Ammonia; Microbiota; Phylogeny
PubMed: 36724219
DOI: 10.1126/sciadv.adg5448 -
Yakugaku Zasshi : Journal of the... 2023Organic nitroxyl radicals represented by 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) are known to be compounds that catalyze alcohol oxidation reactions. These... (Review)
Review
Organic nitroxyl radicals represented by 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) are known to be compounds that catalyze alcohol oxidation reactions. These catalytic reactions can be applied to a wide range of compounds with hydroxy and amino groups. It is also possible to selectively oxidize primary alcohols by designing the skeleton around the nitroxyl radical moiety for use in organic synthesis. Reactions can also be carried out by electrochemical methods, and the electrical current measured during the reaction can be used to quantify the substrates. Therefore, the combination of reactions catalyzed by nitroxyl radicals and electrochemical techniques is expected to be applied as a new analytical method. However, since the reaction does not proceed rapidly in neutral aqueous solutions, it has mostly been applied in basic aqueous solutions or organic solvents, and there have been no reports on sensor applications under physiological conditions. Herein, we have developed a novel catalyst, nortropine N-oxyl (NNO), which is highly active even in neutral aqueous solutions, and have found that it can be used for the analysis of biological components and drugs under physiological conditions. The combination of this method with enzymatic reactions made it possible to specifically detect certain compounds. In this review, we describe a novel analytical method that combines these nitroxyl radicals with electrochemical methods.
Topics: Oxidation-Reduction; Nitrogen Oxides; Catalysis; Water; Free Radicals
PubMed: 36724933
DOI: 10.1248/yakushi.22-00143 -
Photochemistry and Photobiology May 2022Lipid hydroperoxides (LOOHs), including cholesterol- and phospholipid-derived species, are reactive intermediates that arise during photosensitized peroxidation of... (Review)
Review
Lipid hydroperoxides (LOOHs), including cholesterol- and phospholipid-derived species, are reactive intermediates that arise during photosensitized peroxidation of unsaturated lipids in biological membranes. These intermediates may appear in cancer cell membranes during anti-tumor photodynamic therapy (PDT). Photodynamically generated LOOHs have several different fates, including (a) iron-catalyzed one-electron reduction to free radical species which trigger damaging chain peroxidation reactions, (b) selenoperoxidase-catalyzed two-electron reduction to redox-inert alcohols (LOHs), and (c) spontaneous or protein-mediated translocation to other lipid membrane compartments where (a) or (b) may take place. These different LOOH fates will be described in this review, but with special attention to category (c), which the authors were the first to describe and characterize. Seminal early findings on cholesterol hydroperoxide (ChOOH) translocation and its potential negative consequences will be discussed. In reviewing this work, we wish to congratulate Jean Cadet, for his many outstanding accomplishments as a photobiologist and P&P editor.
Topics: Free Radicals; Lipid Peroxidation; Lipid Peroxides; Oxidation-Reduction; Phospholipids
PubMed: 34633674
DOI: 10.1111/php.13537 -
Redox Biology Jan 2020The ketone body β-hydroxybutyrate is no longer viewed simply as a metabolic intermediate, as it regulates a broad range of physiological processes at cellular and... (Review)
Review
The ketone body β-hydroxybutyrate is no longer viewed simply as a metabolic intermediate, as it regulates a broad range of physiological processes at cellular and systemic levels. Particularly, β-hydroxybutyrate functions as a stress response molecule and orchestrates an antioxidant defense program to maintain redox homeostasis in response to environmental and metabolic challenges, such as ischemia. This property of β-hydroxybutyrate might be key for the beneficial effect of calorie restriction on stress response and disease processes.
Topics: 3-Hydroxybutyric Acid; Homeostasis; Ketone Bodies; Oxidation-Reduction
PubMed: 31926621
DOI: 10.1016/j.redox.2019.101395 -
Nature Communications Oct 2023Microbial communication can drive coordinated functions through sensing, analyzing and processing signal information, playing critical roles in biomanufacturing and life...
Microbial communication can drive coordinated functions through sensing, analyzing and processing signal information, playing critical roles in biomanufacturing and life evolution. However, it is still a great challenge to develop effective methods to construct a microbial communication system with coordinated behaviors. Here, we report an electron transfer triggered redox communication network consisting of three building blocks including signal router, optical verifier and bio-actuator for microbial metabolism regulation and coordination. In the redox communication network, the Fe/Fe redox signal can be dynamically and reversibly transduced, channeling electrons directly and specifically into bio-actuator cells through iron oxidation pathway. The redox communication network drives gene expression of electron transfer proteins and simultaneously facilitates the critical reducing power regeneration in the bio-actuator, thus enabling regulation of microbial metabolism. In this way, the redox communication system efficiently promotes the biomanufacturing yield and CO fixation rate of bio-actuator. Furthermore, the results demonstrate that this redox communication strategy is applicable both in co-culture and microbial consortia. The proposed electron transfer triggered redox communication strategy in this work could provide an approach for reducing power regeneration and metabolic optimization and could offer insights into improving biomanufacturing efficiency.
Topics: Biocatalysis; Oxidation-Reduction; Electron Transport; Iron; Microbial Consortia
PubMed: 37884498
DOI: 10.1038/s41467-023-42561-3 -
Redox Biology Oct 2019Nitric Oxide (NO) and Hydrogen Sulfide (HS) are components of an "interactome", which is defined as a redox system involving the interactions of RSS, RNS and ROS.... (Review)
Review
Nitric Oxide (NO) and Hydrogen Sulfide (HS) are components of an "interactome", which is defined as a redox system involving the interactions of RSS, RNS and ROS. Chemical interaction by these species is common and is characterized by one and two electron oxidation, nitrosylation, nitration and sulfuration/polysulfidation reactions. NO and HS are gases that penetrate cell membranes, are synthesized by specific enzymes, are ubiquitous, regulate protein activities through post-translational modifications and participate in cell signaling. The two molecules at high concentrations compared to physiological concentrations may result in cellular damage particularly through their interaction with other reactive species. NO and HS can interact with each other and form a variety of molecular species which may have constructive or destructive behavior depending on the cell type, the cellular environment (ex. oxygen tension, pH, redox state), where the products are produced and in what concentrations. Cross talk exists between NO and HS, whereby they can influence the generation and signaling behavior of each other. Given the above mentioned properties of NO and HS and studies in cancer cells and animal models employing NO and HS donors that generate higher than physiological concentrations of NO and HS and are effective in killing cancer cells but not normal cells, lend credence to the possibility of the utility of these donors in an approach to the treatment of cancer.
Topics: Animals; Antineoplastic Agents; Humans; Hydrogen Sulfide; Neoplasms; Nitric Oxide; Oxidation-Reduction; Protein Processing, Post-Translational; S-Nitrosothiols
PubMed: 30981679
DOI: 10.1016/j.redox.2019.101190