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Heterostructured Catalytic Materials as Advanced Electrocatalysts: Classification, Synthesis, Characterization, and Application

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ADVANCED functionAL MATERIALS 2024年第42期34卷

作者： Wu, Xu Yan, Qiong Wang, Hao Wu, Deyu Zhou, Heng Li, Hui Yang, Song Ma, Tianyi Zhang, Heng Guizhou Univ Ctr Res & Dev Fine Chem Natl Key Lab Green Pesticide State Local Joint Lab Comprehens Utilizat Biomass Guiyang 550025 Guizhou Peoples R China RMIT Univ Sch Sci Melbourne Vic 3000 Australia

The proactive exploration of electrocatalytic conversion for renewable energy valorization is of tremendous significance in addressing the issues of fossil energy exhaustion, among which the critical challenge of electrocatalysis lies in the rational design of efficient electrocatalysts that are rich in the earth. Among electrocatalysts, the design of heterostructured materials exhibits immense potential for the optimization of noble metals and elaboration of non-precious metal electrocatalysts with durability. In this review, a systematic overview of modern advances in heterostructured electrocatalysts for a range of energy conversion reactions is described, and special interfacial design brings additional functional effects. Subsequently, various synthesis methods and characterization techniques for heterostructured electrocatalysts are also summarized. The innovative classification of heterostructures in methods of interfacial junction, crystal structure, structural morphology, and properties of the components is presented in this review. Finally, the possible challenges and outlooks of heterostructured electrocatalysts in the future are further discussed, including how to develop more sophisticated synthesis, characterization, and theoretical calculation methods, which will serve as the guiding direction for a more rational interface design. This review aims to set the trajectory for providing meaningful inspiration and references in energy conversion by heterostructured electrocatalysts, advancing the process of carbon neutrality. Heterostructured materials show amazing electrocatalytic properties based on their tunable interfaces and electronic properties. Here, first, a comprehensive analysis of their properties, preparation, and characterization methods is provided, followed by utilizing plentiful natural resources for sustainable and clean energy conversion, ultimately providing significant insights into exploration of advanced heterostructured catalysts ca

关键词： electrocatalysts energy conversion heterostructures structure-function relationships working mechanisms

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The three-dimensional structure of DapE from Enterococcus faecium reveals new insights into DapE/ArgE subfamily ligand specificity

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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES 2024年第Part2期270卷 132281页

作者： Terrazas-Lopez, Manuel Gonzalez-Segura, Lilian Diaz-Vilchis, Adelaida Aguirre-Mendez, Kelly Annecy Lobo-Galo, Naun Martinez-Martinez, Alejandro Diaz-Sanchez, Angel G. Univ Autonoma Ciudad Juarez Dept Ciencias Quim Biol Inst Ciencias Biomed Ciudad Juarez 32310 Chihuahua Mexico Univ Nacl Autonoma Mexico Fac Quim Dept Bioquim Ciudad Univ Ciudad De Mexico 04510 Mexico

DapE is a Zn2+-metallohydrolase recognized as a drug target for bacterial control. It is a homodimer that requires the exchange of interface strands by an induced fit essential for catalysis. Identifying novel anti-DapE agents requires greater structural details. Most of the characterized DapEs are from the Gram-negative group. Here, two high-resolution DapE crystal structures from Enterococcus faecium are presented for the first time with novel aspects. A loosened enzyme intermediate between the open and closed conformations is observed. Substrates may bind to loose state, subsequently it closes, where hydrolysis occurs, and finally, the change to the open state leads to the release of the products. Mutation of His352 suggests a role, along with His194, in the oxyanion stabilization in the mono-metalated Zn2+ isoform, while in the di-metalated isoform, the metal center 2 complements it function. An aromatic-It box potentially involved in the interaction of DapE with other proteins, and a peptide flip could determine the specificity in the Gram-positive ArgE/DapE group. Finally, details of two extracatalytic cavities whose geometry changes depending on the conformational state of the enzyme are presented. These cavities could be a target for developing non-competitive agents that trap the enzyme in an inactive state.

关键词： Protein crystallography structure-function relationships Enzyme kinetics

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Structural and functional properties of uridine 5′-monophosphate synthase from Coffea arabica

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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES 2024年第Part1期259卷 129226页

作者： Hinojosa-Cruz, Alexis Diaz-Sanchez, Angel G. Diaz-Vilchis, Adelaida Gonzalez-Segura, Lilian Univ Nacl Autonoma Mexico Fac Quim Dept Bioquim Ciudad De Mexico 04510 Mexico Univ Autonoma Ciudad Juarez Dept Ciencias Quim Biol Inst Ciencias Biomed Ciudad Juarez 32310 Chihuahua Mexico Univ Nacl Autonoma Mexico Inst Biotecnol Cuernavaca 62240 Morelos Mexico UNAM Fac Quim Dept Bioquim Ciudad De Mexico 04510 Mexico

In higher eukaryotes and plants, the last two sequential steps in the de novo biosynthesis of uridine 5 '-mono- phosphate (UMP) are catalyzed by a bifunctional natural chimeric protein called UMP synthase (UMPS). In higher plants, UMPS consists of two naturally fused enzymes: orotate phosphoribosyltransferase (OPRTase) at Nterminal and orotidine-5 '-monophosphate decarboxylase (ODCase) at C -terminal. In this work, we obtained the full functional recombinant protein UMPS from Coffea arabica (CaUMPS) and studied its structure-function relationships. A biochemical and structural characterization of a plant UMPS with its two functional domains is described together with the presentation of the first crystal structure of a plant ODCase at 1.4 angstrom resolution. The kinetic parameters measured of CaOPRTase and CaODCase domains were comparable to those reported. The crystallographic structure revealed that CaODCase is a dimer that conserves the typical fold observed in other ODCases from prokaryote and eukaryote with a 1-deoxy-ribofuranose-5 '-phosphate molecule bound in the active site of one subunit induced a closed conformation. Our results add to the knowledge of one of the key enzymes of the de novo biosynthesis of pyrimidines in plant metabolism and open the door to future applications.

关键词： Protein crystallography structure-function relationships enzyme kinetics

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Efficient Non-Precious Metal Catalyst for Propane Dehydrogenation: Atomically Dispersed Cobalt-nitrogen Compounds on Carbon Nanotubes

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CHEMCATCHEM 2021年第13期13卷 3067-3073页

作者： Cao, Tianlong Dai, Xueya Li, Fan Liu, Weijie Bai, Yunli Fu, Yu Qi, Wei Northeastern Univ Dept Chem Coll Sci 3-11 Wenhua Rd Shenyang 110819 Peoples R China Chinese Acad Sci Shenyang Natl Lab Mat Sci Inst Met Res 72 Wenhua Rd Shenyang 110016 Peoples R China

A hybrid catalyst comprising atomically dispersed cobalt-nitrogen compounds anchoring on oxidized carbon nanotubes (OCNTs) is prepared and applied in propane dehydrogenation (PDH) reactions. The proposed non-precious catalyst exhibits high initial conversion (similar to 20 %) and excellent selectivity of propene (>95 %), which is superior to those of metal-free nanocarbon and some metal-based catalysts. The chemical composition and structure of the proposed hybrid catalysts are elucidated by a series of characterizations and control experiments with a single component. These characterization results combined with the kinetic analysis indicate that the catalytic activity mainly originates from the cobalt-nitrogen (Co-N) species supported on the OCNT surface. The present work sheds light on the structure-function relationships of CoN catalysts, paving the way to develop non-precious catalysts for PDH reactions.

关键词： propane dehydrogenation atomically dispersed cobalt-nitrogen compounds structure-function relationships

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Photochemical CO₂ Reduction Using Rhenium(I) Tricarbonyl Complexes with Bipyridyl-Type Ligands with and without Second Coordination Sphere Effects

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CHEMPHOTOCHEM 2021年第6期5卷 526-537页

作者： Rotundo, Laura Grills, David C. Gobetto, Roberto Priola, Emanuele Nervi, Carlo Polyansky, Dmitry E. Fujita, Etsuko Univ Torino Chem Dept Via P Giuria 7 I-10125 Turin Italy CIRCC Via Celso Ulpiani 27 I-70126 Bari Italy Brookhaven Natl Lab Chem Div Upton NY 11973 USA

The effect of phenyl, phenol, aniline, amino, and CF substituents of the 2,2'-bipyridine ligand in toc-ReCl(L)(CO)(3) (L-2,2'-bipyridine derivative) catalysts on photochemical CO2 reduction in dimethylacetamide is examined, in order to understand the structure-function relationships and to compare the catalytic activities with the previously published electrochemical results. All complexes including ReCl(bpy)(CO)(3) have similar excitedstate lifetimes and emission spectra, but complex 1 with the Ph-NH2 moiety exhibits a significantly larger molar absorption coefficient for its metal-to-ligand charge transfer (MLCT) band. All complexes we tested produce CO with only a negligible amount of H-2 and formate in self-sensitized systems in the presence of triethanolamine (TEOA) and in some cases, BIH (1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]-imidazole). The presence of the Ph-NH2 moiety (complex 1) has a beneficial effect on both electrochemical and photochemical activity, allowing a turnover number (TON) of 32 and 120 for photochemical CO production (without and with BIH, respectively). In the case of the Ph-OH group in the second coordination sphere (complexes 4 and 6), these complexes are active for photochemical CO2 reduction, despite the formation of a stable 6-coordinate Re-OPh intermediate via reductive deprotonation as previously observed under electrochemical conditions. Overall, BIH accelerates the rate of formation of the one-electron reduced species (OERS) of the Re catalysts and allows higher turnover frequency (TOF) and TON for CO formation. The X-ray structures of complexes 1 and 4 were determined to have distorted octahedral Re centres, and show pi-pi stacking interactions with neighboring molecules as well as intramolecular hydrogen bonds to the internal chloride ligands. The unusually high absorptivity of the MLCT absorption of complex 1 has been explained by TD-DFT calculations.

关键词： carbon dioxide reduction photocatalysis reductive deprotonation rhenium structure-function relationships

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Bimetallic-Derived Catalysts and Their Application in Simultaneous Upgrading of CO₂ and Ethane

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MATTER 2021年第2期4卷 408-440页

作者： Xie, Zhenhua Winter, Lea R. Chen, Jingguang G. Brookhaven Natl Lab Chem Div Upton NY 11973 USA Columbia Univ Dept Chem Engn New York NY 10027 USA

Bimetallic-derived catalysts have played a pivotal role in many industrially important catalytic processes. In recent years, simultaneously upgrading the greenhouse gas CO2 and underutilized ethane (SU-CO2Et) has represented a promising route for producing value-added chemicals, such as synthesis gas and olefin. This review focuses on the synthesis and characterization of precious and non-precious bimetallic-derived catalysts and their application in SU-CO2Et. We discuss general principles and state-of-the-art strategies for catalyst synthesis, aswell as in situ techniques for structural characterization and mechanistic insights. We then illustrate how to design and apply versatile bimetallic-derived catalysts for SU-CO2Et and to establish structure-function relationships by using combined experimental and theoretical approaches. We conclude the review by highlighting challenges and opportunities in activesite design and synthesis, in situ structural and mechanistic identification, and development of multifunctional bimetallic-derived catalysts for further upgrading abundant CO2 and shale gas into valuable aromatics and oxygenates.

关键词： heterogeneous catalysis materials synthesis bimetallic-derived catalysts CO2 ethane syngas ethylene shale gas in situ and/or operando characterizations structure-function relationships

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Structural basis of the selective activation of enzyme isoforms: Allosteric response to activators of β1- and β2-containing AMPK complexes

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COMPUTATIONAL AND STRUCTURAL BIOTECHNOLOGY JOURNAL 2021年 19卷 3394-3406页

作者： Aledavood, Elnaz Forte, Alessia Estarellas, Carolina Luque, F. Javier Univ Barcelona Dept Nutr Food Sci & Gastron Fac Pharm & Food Sci Inst Biomed IBUB Av Prat de la Riba 171 Santa Coloma De Gramenet 08921 Spain Univ Barcelona Inst Theoret & Computat Chem IQTCUB Av Prat de la Riba 171 Santa Coloma De Gramenet 08921 Spain

AMP-activated protein kinase (AMPK) is a key energy sensor regulating the cell metabolism in response to energy supply and demand. The evolutionary adaptation of AMPK to different tissues is accomplished through the expression of distinct isoforms that can form up to 12 complexes, which exhibit notable differences in the sensitivity to allosteric activators. To shed light into the molecular determinants of the allosteric regulation of this energy sensor, we have examined the structural and dynamical properties of beta 1-and beta 2-containing AMPK complexes formed with small molecule activators A-769662 and SC4, and dissected the mechanical response leading to active-like enzyme conformations through the analysis of interaction networks between structural domains. The results reveal the mechanical sensitivity of the alpha 2 beta 1 complex, in contrast with a larger resilience of the alpha 2 beta 2 species, especially regarding modulation by A-769662. Furthermore, binding of activators to alpha 2 beta 1 consistently promotes the pre-organization of the ATP-binding site, favoring the adoption of activated states of the enzyme. These findings are discussed in light of the changes in the residue content of beta-subunit isoforms, particularly regarding the beta 1Asn111 -> beta 2Asp111 substitution as a key factor in modulating the mechanical sensitivity of beta 1- and beta 2-containing AMPK complexes. Our studies pave the way for the design of activators tailored for improving the therapeutic treatment of tissue-specific metabolic disorders. (C) 2021 The Author(s). Published by Elsevier B.V. on behalf of Research Network of Computational and Structural Biotechnology.

关键词： Enzyme isoforms Allostery Enzyme activation AMPK structure-function relationships Protein dynamics

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The Impact of Microbial Interactions on Ecosystem function Intensifies Under Stress

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ECOLOGY LETTERS 2024年第10期27卷 e14528页

作者： Bertolet, Brittni L. Rodriguez, Luciana Chavez Murua, Jose M. Favela, Alonso Allison, Steven D. Univ Calif Irvine Dept Ecol & Evolutionary Biol Irvine CA 92697 USA Univ Arizona Sch Plant Sci Tucson AZ USA Univ Calif Irvine Dept Earth Syst Sci Irvine CA USA

A major challenge in ecology is to understand how different species interact to determine ecosystem function, particularly in communities with large numbers of co-occurring species. We use a trait-based model of microbial litter decomposition to quantify how different taxa impact ecosystem function. Furthermore, we build a novel framework that highlights the interplay between taxon traits and environmental conditions, focusing on their combined influence on community interactions and ecosystem function. Our results suggest that the ecosystem impact of a taxon is driven by its resource acquisition traits and the community functional capacity, but that physiological stress amplifies the impact of both positive and negative interactions. Furthermore, net positive impacts on ecosystem function can arise even as microbes have negative pairwise interactions with other taxa. As communities shift in response to global climate change, our findings reveal the potential to predict the biogeochemical functioning of communities from taxon traits and interactions.

关键词： drought exploitation extracellular enzymes facilitation litter decomposition microbial community assembly public goods resource-based interactions structure-function relationships

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L-serine deficiency: on the properties of the Asn133Ser variant of human phosphoserine phosphatase

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SCIENTIFIC REPORTS 2024年第1期14卷 1-14页

作者： Pollegioni, Loredano Campanini, Barbara Good, Jean-Marc Motta, Zoraide Murtas, Giulia Buoli Comani, Valeria Pavlidou, Despina-Christina Mercier, Noelle Mittaz-Crettol, Laureane Sacchi, Silvia Marchesani, Francesco Univ Insubria Dept Biotechnol & Life Sci Via JH Dunant 3 I-21100 Varese Italy Univ Parma Dept Food & Drug I-43124 Parma Italy Univ Lausanne Lausanne Univ Hosp CHUV Div Genet Med CH-1011 Lausanne Switzerland Inst Lavigny Dept Epileptol Lavigny Switzerland Univ Parma Dept Med & Surg I-43121 Parma Italy

The non-essential amino acid L-serine is involved in a number of metabolic pathways and in the brain its level is largely due to the biosynthesis from the glycolytic intermediate D-3-phosphoglycerate by the phosphorylated pathway (PP). This cytosolic pathway is made by three enzymes proposed to generate a reversible metabolon named the "serinosome". Phosphoserine phosphatase (PSP) catalyses the last and irreversible step, representing the driving force pushing L-serine synthesis. Genetic defects of the PP enzymes result in strong neurological phenotypes. Recently, we identified the homozygous missense variant [NM_004577.4: c.398A > G p.(Asn133Ser)] in the PSPH, the PSP encoding gene, in two siblings with a neurodevelopmental syndrome and a myelopathy. The recombinant Asn133Ser enzyme does not show significant alterations in protein conformation and dimeric oligomerization state, as well as in enzymatic activity and functionality of the reconstructed PP. However, the Asn133Ser variant is less stable than wild-type PSP, a feature also apparent at cellular level. Studies on patients' fibroblasts also highlight a strong decrease in the level of the enzymes of the PP, a partial nuclear and perinuclear localization of variant PSP and a stronger perinuclear aggregates formation. We propose that these alterations contribute to the formation of a dysfunctional serinosome and thus to the observed reduction of L-serine, glycine and D-serine levels (the latter playing a crucial role in modulating NMDA receptors). The characterization of patients harbouring the Asn133Ser PSP substitution allows to go deep into the molecular mechanisms related to L-serine deficit and to suggest treatments to cope with the observed amino acids alterations.

关键词： Serine deficiency Phosphorylated pathway Genetic disease structure-function relationships

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Reconfigurable Micro- and Nano-structured Camouflage Surfaces Inspired by Cephalopods

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ACS NANO 2021年第11期15卷 17299-17309页

作者： Liu, Yinuan Feng, Zhijing Xu, Chengyi Chatterjee, Atrouli Gorodetsky, Alon A. Univ Calif Irvine Dept Chem Irvine CA 92697 USA Univ Calif Irvine Dept Chem & Biomol Engn Irvine CA 92697 USA Univ Calif Irvine Dept Mat Sci & Engn Irvine CA 92697 USA Univ Calif Irvine Dept Chem Dept Chem & Biomol Engn Irvine CA 92697 USA

Wrinkled surfaces and materials are found throughout the natural world in various plants and animals and are known to improve the performance of emerging optical and electrical technologies. Despite much progress, the reversible post-fabrication tuning of wrinkle sizes and geo-metries across multiple length scales has remained relatively challenging for some materials, and the development of comprehensive structure-function relationships for optically active wrinkled surfaces has often proven difficult. Herein, by drawing inspiration from natural cephalopod skin and leveraging methodologies established for artificial adaptive infrared platforms, we engineer systems with hierarchically reconfigurable wrinkled surface morphologies and dynamically tunable visible-to-infrared spectroscopic properties. Specifically, we demonstrate architectures for which mechanical actuation changes the surface morphological characteristics;modulates the reflectance, transmittance, and absorptance across a broad spectral window;controls the specular-to-diffuse reflectance ratios;and alters the visible and thermal appearances. Moreover, we demonstrate the incorporation of these architectures into analogous electrically actuated appearance-changing devices that feature competitive figures of merit, such as reasonable maximum areal strains, rapid response times, and good stabilities upon repeated actuation. Overall, our findings constitute another step forward in the continued development of cephalopod-inspired light- and heat-manipulating systems and may facilitate advanced applications in the areas of sensing, electronics, optics, soft robotics, and thermal management.

关键词： bioinspired systems cephalopods camouflage devices soft actuators wrinkled surfaces structure-function relationships

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