Reversible and cooperative photoactivation of single-atom Cu/TiO2 photocatalysts

Nature Materials, Journal Year: 2019, Volume and Issue: 18(6), P. 620 - 626

Published: April 22, 2019

Language: Английский

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Using nature’s blueprint to expand catalysis with Earth-abundant metals

Science, Journal Year: 2020, Volume and Issue: 369(6505)

Published: Aug. 14, 2020

Making chemistry less precious Much of modern relies on catalysis by metals such as platinum, palladium, and rhodium. By contrast, more abundant iron copper suffice in biochemistry. Bullock et al. review the opportunities presented from study enzymes to shift balance synthetic catalysts further toward use these metals. Whether modifying themselves or designing ligand support architectures that take advantage cheaper metals' characteristic electron transfer properties, recent work points substantial progress. Science , this issue p. eabc3183

Language: Английский

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Trace metal metabolism in plants

Journal of Experimental Botany, Journal Year: 2017, Volume and Issue: 69(5), P. 909 - 954

Published: Dec. 13, 2017

Many trace metals are essential micronutrients, but also potent toxins. Due to natural and anthropogenic causes, vastly different metal concentrations occur in various habitats, ranging from deficient toxic levels. Therefore, one focus of plant research is on the response terms uptake, transport, sequestration, speciation, physiological use, deficiency, toxicity, detoxification. In this review, we cover most these aspects for micronutrients copper, iron, manganese, molybdenum, nickel, zinc provide a broader overview than found other recent reviews, cross-link knowledge very active field that often seen separated way. For example, individual processes usage, or toxicity were not mechanistically interconnected. review aims stimulate communication researchers following approaches, such as gene expression analysis, biochemistry, biophysics metalloproteins. Furthermore, highlight insights, emphasizing data obtained under physiologically environmentally relevant conditions.

Language: Английский

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O₂Reduction in Enzymatic Biofuel Cells

Chemical Reviews, Journal Year: 2017, Volume and Issue: 118(5), P. 2392 - 2468

Published: Sept. 20, 2017

Catalytic four-electron reduction of O2 to water is one the most extensively studied electrochemical reactions due exceptional availability and high O2/H2O redox potential, which may in particular allow highly energetic fuel cells. To circumvent use expensive inefficient Pt catalysts, multicopper oxidases (MCOs) have been envisioned because they provide efficient with almost no overpotential. MCOs used elaborate enzymatic biofuel cells (EBFCs), a subclass enzymes replace conventional catalysts. A glucose/O2 EBFC, glucose oxidizing anode reducing MCO cathode, could become vivo source electricity that would power sometimes future integrated medical devices. This review covers challenges advances electrochemistry their EBFCs emphasis on last 6 years. First basic features are presented. Clues provided by understand these how behave once connected at electrodes described. Progresses realized development biocathodes for relying both direct mediated electron transfer mechanism then discussed. Some implementations finally

Language: Английский

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Synthesis and Characterization of Iron–Nitrogen-Doped Graphene/Core–Shell Catalysts: Efficient Oxidative Dehydrogenation of N-Heterocycles

Journal of the American Chemical Society, Journal Year: 2015, Volume and Issue: 137(33), P. 10652 - 10658

Published: July 31, 2015

An important goal for nanocatalysis is the development of flexible and efficient methods preparing active stable core-shell catalysts. In this respect, we present synthesis characterization iron oxides surrounded by nitrogen-doped-graphene shells immobilized on carbon support (labeled FeOx@NGr-C). Active catalytic materials are obtained in a simple, scalable two-step method via pyrolysis acetate phenanthroline subsequent selective leaching. The optimized FeOx@NGr-C catalyst showed high activity oxidative dehydrogenations several N-heterocycles. utility benign methodology demonstrated pharmaceutically relevant quinolines. addition, mechanistic studies prove that reaction progresses superoxide radical anions (·O2(-)).

Language: Английский

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Multifunctional Cytochrome c: Learning New Tricks from an Old Dog

Chemical Reviews, Journal Year: 2017, Volume and Issue: 117(21), P. 13382 - 13460

Published: Oct. 13, 2017

Cytochrome c (cyt c) is a small soluble heme protein characterized by relatively flexible structure, particularly in the ferric form, such that it able to sample broad conformational space. Depending on specific conditions, interactions, and cellular localization, different conformations may be stabilized, which differ redox properties, binding affinities, enzymatic activity. The primary function electron shuttling oxidative phosphorylation, exerted so-called native cyt intermembrane mitochondrial space of healthy cells. Under pro-apoptotic however, gains cardiolipin peroxidase activity, translocates into cytosol engage intrinsic apoptotic pathway, enters nucleus where impedes nucleosome assembly. Other reported functions include cytosolic sensing involvement folding machinery. Moreover, post-translational modifications as nitration, sulfoxidation amino acids induce alternative with differential at least vitro. Similar structural functional alterations are elicited biologically significant electric fields naturally occurring mutations human that, along level maturation system, associated diseases. Here, we summarize current knowledge recent advances understanding structural, dynamic, thermodynamic factors regulate transfer function, well c. Finally, present technological applications this moonlighting protein.

Language: Английский

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Synthetic Fe/Cu Complexes: Toward Understanding Heme-Copper Oxidase Structure and Function

Chemical Reviews, Journal Year: 2018, Volume and Issue: 118(22), P. 10840 - 11022

Published: Oct. 29, 2018

Heme-copper oxidases (HCOs) are terminal enzymes on the mitochondrial or bacterial respiratory electron transport chain, which utilize a unique heterobinuclear active site to catalyze 4H+/4e– reduction of dioxygen water. This process involves proton-coupled transfer (PCET) from tyrosine (phenolic) residue and additional redox events coupled transmembrane proton pumping ATP synthesis. Given that HCOs large, complex, membrane-bound enzymes, bioinspired synthetic model chemistry is promising approach better understand heme–Cu-mediated reduction, including details movements. review encompasses important aspects heme–O2 copper–O2 (bio)chemistries as they relate design interpretation small molecule systems provides perspectives fundamental coordination chemistry, can be applied understanding HCO activity. We focus recent advancements studies heme–Cu models, evaluating experimental computational results, highlight structure–function relationships. Finally, we provide an outlook for future potential contributions inorganic discuss their implications with relevance biological O2-reduction.

Language: Английский

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Methanotrophs: Discoveries, Environmental Relevance, and a Perspective on Current and Future Applications

Frontiers in Microbiology, Journal Year: 2021, Volume and Issue: 12

Published: May 14, 2021

Methane is the final product of anaerobic decomposition organic matter. The conversion matter to methane (methanogenesis) as a mechanism for energy conservation exclusively attributed archaeal domain. oxidized by methanotrophic microorganisms using oxygen or alternative terminal electron acceptors. Aerobic bacteria belong phyla Proteobacteria and Verrucomicrobia, while oxidation also mediated more recently discovered methanotrophs with representatives in both archaea domains. coupled reduction nitrate, nitrite, iron, manganese, sulfate, acceptors (e.g., humic substances) This review highlights relevance methanotrophy natural anthropogenically influenced ecosystems, emphasizing environmental conditions, distribution, function, co-existence, interactions, availability that likely play key role regulating their function. A systematic overview aspects ecology, physiology, metabolism, genomics crucial understand contribution mitigation efflux atmosphere. We give significance processes under microaerophilic conditions aerobic oxidizers. In context we emphasize current potential future applications from two different angles, namely wastewater treatment through application methanotrophs, biotechnological resource recovery waste streams. Finally, identify knowledge gaps may lead opportunities harness further benefits production valuable bioproducts enabling bio-based circular economy.

Language: Английский

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Reactivity, Mechanism, and Assembly of the Alternative Nitrogenases

Chemical Reviews, Journal Year: 2020, Volume and Issue: 120(12), P. 5107 - 5157

Published: March 4, 2020

Biological nitrogen fixation is catalyzed by the enzyme nitrogenase, which facilitates cleavage of relatively inert triple bond N2. Nitrogenase most commonly associated with molybdenum–iron cofactor called FeMoco or M-cluster, and it has been subject extensive structural spectroscopic characterization over past 60 years. In late 1980s early 1990s, two "alternative nitrogenase" systems were discovered, isolated, found to incorporate V Fe in place Mo. These are regulated separate gene clusters; however, there a high degree functional similarity between each nitrogenase. Limited studies V- Fe-nitrogenases initially demonstrated that these enzymes analogously active as Mo-nitrogenase, but more recent investigations have capabilities unique alternative systems. this review, we will discuss reactivity, biosynthetic, mechanistic proposals for nitrogenases well their electronic properties comparison well-characterized Mo-dependent system. Studies 10 years particularly fruitful, though key aspects about remain unexplored.

Language: Английский

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Cystathionine-β-synthase: Molecular Regulation and Pharmacological Inhibition

Biomolecules, Journal Year: 2020, Volume and Issue: 10(5), P. 697 - 697

Published: April 30, 2020

Cystathionine-β-synthase (CBS), the first (and rate-limiting) enzyme in transsulfuration pathway, is an important mammalian health and disease. Its biochemical functions under physiological conditions include metabolism of homocysteine (a cytotoxic molecule cardiovascular risk factor) generation hydrogen sulfide (H2S), a gaseous biological mediator with multiple regulatory roles vascular, nervous, immune system. CBS up-regulated several diseases, including Down syndrome many forms cancer; these conditions, preclinical data indicate that inhibition or inactivation exerts beneficial effects. This article overviews current information on expression, tissue distribution, roles, biochemistry CBS, followed by comprehensive overview direct indirect approaches to inhibit enzyme. Among small-molecule inhibitors, review highlights specificity selectivity problems related commonly used “CBS inhibitors” (e.g., aminooxyacetic acid) provides their pharmacological actions various disease models.

Language: Английский

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