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ELife Aug 2020In order to enter a cell, an ammonium ion must first dissociate to form an ammonia molecule and a hydrogen ion (a proton), which then pass through the cell membrane...
In order to enter a cell, an ammonium ion must first dissociate to form an ammonia molecule and a hydrogen ion (a proton), which then pass through the cell membrane separately and recombine inside.
Topics: Ammonia; Ammonium Compounds; Ion Transport; Nitrosomonas; Oxidation-Reduction
PubMed: 32840481
DOI: 10.7554/eLife.61148 -
Experimental & Molecular Medicine Nov 2016Evidence indicates that hypoxia and oxidative stress can control metabolic reprogramming of cancer cells and other cells in tumor microenvironments and that the... (Review)
Review
Evidence indicates that hypoxia and oxidative stress can control metabolic reprogramming of cancer cells and other cells in tumor microenvironments and that the reprogrammed metabolic pathways in cancer tissue can also alter the redox balance. Thus, important steps toward developing novel cancer therapy approaches would be to identify and modulate critical biochemical nodes that are deregulated in cancer metabolism and determine if the therapeutic efficiency can be influenced by changes in redox homeostasis in cancer tissues. In this review, we will explore the molecular mechanisms responsible for the metabolic reprogramming of tumor microenvironments, the functional modulation of which may disrupt the effects of or may be disrupted by redox homeostasis modulating cancer therapy.
Topics: Animals; Antineoplastic Agents; Glucose; Homeostasis; Humans; Metabolic Networks and Pathways; Molecular Targeted Therapy; Neoplasms; Oxidation-Reduction; Oxidative Stress; Reactive Oxygen Species; Tumor Microenvironment
PubMed: 27811934
DOI: 10.1038/emm.2016.119 -
Biological Chemistry Jan 2021
Topics: Oxidation-Reduction; Protein Processing, Post-Translational; Proteins; Sulfhydryl Compounds
PubMed: 33544502
DOI: 10.1515/hsz-2020-0387 -
International Journal of Molecular... Nov 2022Many studies demonstrate the safety of alkaline-electrolyzed-reduced water (ERW); however, several animal studies have reported significant tissue damage and... (Review)
Review
Many studies demonstrate the safety of alkaline-electrolyzed-reduced water (ERW); however, several animal studies have reported significant tissue damage and hyperkalemia after drinking ERW. The mechanism responsible for these results remains unknown but may be due to electrode degradation associated with the production of higher pH, in which platinum nanoparticles and other metals that have harmful effects may leach into the water. Clinical studies have reported that, when ERW exceeds pH 9.8, some people develop dangerous hyperkalemia. Accordingly, regulations on ERW mandate that the pH of ERW should not exceed 9.8. It is recommended that those with impaired kidney function refrain from using ERW without medical supervision. Other potential safety concerns include impaired growth, reduced mineral, vitamin, and nutrient absorption, harmful bacterial overgrowth, and damage to the mucosal lining causing excessive thirst. Since the concentration of H in ERW may be well below therapeutic levels, users are encouraged to frequently measure the H concentration with accurate methods, avoiding ORP or ORP-based H meters. Importantly, although, there have been many people that have used high-pH ERW without any issues, additional safety research on ERW is warranted, and ERW users should follow recommendations to not ingest ERW above 9.8 pH.
Topics: Animals; Water; Electrolysis; Hydrogen; Metal Nanoparticles; Platinum; Hydrogen-Ion Concentration; Oxidation-Reduction
PubMed: 36498838
DOI: 10.3390/ijms232314508 -
Molecules (Basel, Switzerland) Nov 2014All forms of life maintain a reducing environment (homeostasis) within their cells. Perturbations in the normal redox state can lead to an oxidative environment which... (Review)
Review
All forms of life maintain a reducing environment (homeostasis) within their cells. Perturbations in the normal redox state can lead to an oxidative environment which has deleterious effects, especially in health. In biological systems, metabolic activities are dependent mainly on mitochondrial oxidative phosphorylation, a metabolic pathway that uses energy released by the oxidation of nutrients to produce ATP. In the process of oxidative phosphorylation, electrons are transferred from electron donors to electron acceptors such as oxygen in redox reactions and often results to the generation of reactive species. Reactive oxygen species consist of a class of radical and non-radical oxygen derivatives. The imbalance between the reactive oxygen species and antioxidant defence systems leads to oxidative burden and hence, damage biological molecules. Antioxidants help to prevent or fix the deleterious effects of reactive species. Sulfur is an important element in biological systems. This atom is usually integrated into proteins as the redox-active cysteine residue and in molecules such as glutathione, thioredoxin and glutaredoxin which are vital antioxidant molecules and are therefore essential for life. This review covers the role of sulfur containing antioxidant systems in oxidative environments.
Topics: Antioxidants; Oxidation-Reduction; Sulfur; Sulfur Compounds
PubMed: 25429562
DOI: 10.3390/molecules191219376 -
Trends in Biochemical Sciences Aug 2022The electron transport chain (ETC) is a major currency converter that exchanges the chemical energy of fuel oxidation to proton motive force and, subsequently, ATP... (Review)
Review
The electron transport chain (ETC) is a major currency converter that exchanges the chemical energy of fuel oxidation to proton motive force and, subsequently, ATP generation, using O as a terminal electron acceptor. Discussed herein, two new studies reveal that the mammalian ETC is forked. Hypoxia or HS exposure promotes the use of fumarate as an alternate terminal electron acceptor. The fumarate/succinate and CoQH/CoQ redox couples are nearly iso-potential, revealing that complex II is poised for facile reverse electron transfer, which is sensitive to CoQH and fumarate concentrations. The gas regulators, HS and NO, modulate O affinity and/or inhibit the electron transfer rate at complex IV. Their induction under hypoxia suggests a mechanism for how traffic at the ETC fork can be regulated.
Topics: Animals; Electron Transport; Electrons; Fumarates; Hypoxia; Mammals; Oxidation-Reduction
PubMed: 35397924
DOI: 10.1016/j.tibs.2022.03.011 -
STAR Protocols Dec 2022Anilines are important feedstocks for pharmaceuticals, dyes, and other materials, but traditional approaches to their syntheses usually lack selectivity and...
Anilines are important feedstocks for pharmaceuticals, dyes, and other materials, but traditional approaches to their syntheses usually lack selectivity and environmental sustainability. Here, we describe the selective reduction of nitrobenzene to aniline under mild conditions, using water as the ultimate source of the required protons and electrons. We describe the electrochemical cell assembly, and detail steps for electrochemical reduction followed by organic extraction and analysis of the extracts using NMR. For complete details on the use and execution of this protocol, please refer to Stergiou and Symes (2022a).
Topics: Nitrobenzenes; Oxidation-Reduction; Electrons
PubMed: 36386882
DOI: 10.1016/j.xpro.2022.101817 -
Journal of Hazardous Materials Feb 2022Bioreduction can facilitate oxyanions removal from wastewater. However, simultaneously removing selenate, nitrate and sulfate and recovering high-purity elemental...
Bioreduction can facilitate oxyanions removal from wastewater. However, simultaneously removing selenate, nitrate and sulfate and recovering high-purity elemental selenium (Se) from wastewater by a single system is difficult and may lead to carcinogenic selenium monosulfide (SeS) formation. To solve this issue, a two-stage biological fluidized bed (FBR) process with ethanol dosing based on oxidation-reduction potential (ORP) feedback control was developed in this study. FBR1 performance was first evaluated at various ORP setpoints (between -520 and -360 mV vs. Ag/AgCl) and elevated sulfate concentration. Subsequently, ethanol-fed FBR2 was used to reduce sulfate from FBR1 effluent, followed by an aerated sulfide oxidation reactor (SOR). At - 520 mV≤ ORPs≤ -480 mV, FBR1 removed 100 ± 0.1% nitrate and 99.7 ± 0.3% selenate without sulfate reduction. At ORPs ≥ -440 mV, selenate reduction was incomplete, whereas nitrate removal remained stable. Se recovery efficiency from FBR1 effluent was 37.5% with 71% Se purity. FBR2 converted 86% of the remaining sulfate in FBR1 effluent to hydrogen sulfide, but the over-oxidation of dissolved sulfide in SOR decreased the overall sulfate removal efficiency to ~46.3%. Overall, the two-stage FBR process with ORP feedback dosing of ethanol was effective for sequentially removing selenate, nitrate and sulfate and recovering Se from wastewater.
Topics: Bioreactors; Feedback; Nitrates; Oxidation-Reduction; Selenic Acid; Selenium; Sulfates
PubMed: 34800843
DOI: 10.1016/j.jhazmat.2021.127539 -
International Journal of Molecular... Mar 2023It is with great pleasure that we introduce this Special Issue on "Homeostasis: Metals and Cellular Redox and Immunity Status" [...].
It is with great pleasure that we introduce this Special Issue on "Homeostasis: Metals and Cellular Redox and Immunity Status" [...].
Topics: Metals; Oxidation-Reduction; Homeostasis
PubMed: 36902319
DOI: 10.3390/ijms24054889 -
American Journal of Physiology. Heart... Sep 2017
Topics: Acetylation; Fatty Acids; Mitochondrial Proteins; Myocardium; Oxidation-Reduction
PubMed: 28646027
DOI: 10.1152/ajpheart.00303.2017