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activesites, etc ; adsorption; density functional theory; dissociation; oxidation; oxygen; China; Show all 7 Subjects
Abstract:
... Based on the experimental and theoretical methods, the NO selective catalytic oxidation process was proposed. The experimental results indicated that lattice oxygen was the active site for NO oxide over the α-MnO₂(110) surface. In the theoretical study, DFT (density functional theory) and periodic slab modeling were performed on an α-MnO₂(110) surface, and two possible NO oxidation mechanisms over ...
... Mineral dust is an important type of ice nucleating particles in the troposphere; however, the effects of heterogeneous reactions on ice nucleation (IN) activities of mineral dust remain to be elucidated. A droplet-freezing apparatus (Guangzhou Institute of Geochemistry Ice Nucleation Apparatus, GIGINA) was developed in this work to measure IN activities of atmospheric particles in the immersion f ...
Juan Luis Pacheco-Garcia; Dmitry S. Loginov; Ernesto Anoz-Carbonell; Pavla Vankova; Rogelio Palomino-Morales; Eduardo Salido; Petr Man; Milagros Medina; Athi N. Naganathan; Angel L. Pey
activesites, etc ; leucine; mutation; proteins; solubility; Show all 5 Subjects
Abstract:
... Allosterism is a common phenomenon in protein biochemistry that allows rapid regulation of protein stability; dynamics and function. However, the mechanisms by which allosterism occurs (by mutations or post-translational modifications (PTMs)) may be complex, particularly due to long-range propagation of the perturbation across protein structures. In this work, we have investigated allosteric commu ...
activesites, etc ; catalysts; catalytic activity; haptens; thermodynamics; Show all 5 Subjects
Abstract:
... A simple abiological host–guest system demonstrates racemase activity with catalytic rate enhancements of 10⁴ without employing traditional functional groups. Cooperative weak interactions enhanced through shape-complementarity between the catalyst active site and the reaction transition state drive this activity, as proposed by Pauling for enzymes. In analogy to the Jencks’ concept of catalytic a ...
activesites, etc ; electrochemistry; electron transfer; metalloproteins; mutants; Show all 5 Subjects
Abstract:
... Long-range electron tunneling through metalloproteins is facilitated by evolutionary tuning of donor–acceptor electronic couplings, formal electrochemical potentials, and active-site reorganization energies. Although the minimal frustration of the folding landscape enables this tuning, residual frustration in the vicinity of the metallocofactor can allow conformational fluctuations required for pr ...
activesites, etc ; RNA helicases; exons; humans; spliceosomes; Show all 5 Subjects
Abstract:
... Pre-mRNA splicing involves two sequential reactions: branching and exon ligation. The C complex after branching undergoes remodeling to become the C∗ complex, which executes exon ligation. Here, we report cryo-EM structures of two intermediate human spliceosomal complexes, pre-C∗-I and pre-C∗-II, both at 3.6 Å. In both structures, the 3′ splice site is already docked into the active site, the ensu ...
activesites, etc ; light; nickel; photocatalysis; photocatalysts; semiconductors; tetracycline; Show all 7 Subjects
Abstract:
... To investigate the mechanism of bimetallic 2-dimension (2D) catalyst existing in the current photocatalytic degradation process, the tetracycline (TC) degradation performance and mechanism by bimetallic 2D photocatalyst was studied extensively. Nickel metal-organic layer (Ni-MOL) and In₂Se₃, a typical 2D semiconductor photocatalyst, shows great potential for photocatalytic degradation of TC. Herei ...
Yun Shi; Philip S. Kerry; Jeffrey D. Nanson; Todd Bosanac; Yo Sasaki; Raul Krauss; Forhad K. Saikot; Sarah E. Adams; Tamim Mosaiab; Veronika Masic; Xianrong Mao; Faith Rose; Eduardo Vasquez; Marieke Furrer; Katie Cunnea; Andrew Brearley; Weixi Gu; Zhenyao Luo; Lou Brillault; Michael J. Landsberg; Aaron DiAntonio; Bostjan Kobe; Jeffrey Milbrandt; Robert O. Hughes; Thomas Ve
activesites, etc ; NAD (coenzyme); axons; moieties; nicotinamide; therapeutics; Show all 6 Subjects
Abstract:
... The NADase SARM1 (sterile alpha and TIR motif containing 1) is a key executioner of axon degeneration and a therapeutic target for several neurodegenerative conditions. We show that a potent SARM1 inhibitor undergoes base exchange with the nicotinamide moiety of nicotinamide adenine dinucleotide (NAD⁺) to produce the bona fide inhibitor 1AD. We report structures of SARM1 in complex with 1AD, NAD⁺ ...
activesites, etc ; catalytic activity; crystal structure; operon; thermophiles; zinc; Show all 6 Subjects
Abstract:
... Zinc peptidase M16 family members are widely distributed in most prokaryotic and eukaryotic organisms. M16 family has been divided into three subfamilies, M16A, M16B and M16C, based on sequence alignments and subunit connectivity. TTHA1264, an M16B protein found in Thermus thermophiles HB8, possesses an HXXEH motif essential for Zn²⁺ binding and catalytic activity. TTHA1265 is another member of M1 ...
activesites, etc ; adsorption; carbon dioxide; desorption; gasification; graphene; oxygen; Show all 7 Subjects
Abstract:
... Reactions of carbon and oxygen containing molecules, such as O₂, NO, H₂O and CO₂, are ubiquitous on earth and the universe. Through ab initio calculations, we study the reactions of H₂O and CO₂ with small graphene clusters containing armchair edges, both H- and non-H terminated, and compare with studies of zigzag carbon edges interacting with oxygen-containing molecules. Our results highlight the ...
activesites, etc ; adsorption; cost effectiveness; hydrogen; photocatalysis; photoreduction; selenium; Show all 7 Subjects
Abstract:
... Cost-effective 2D metal-selenides are verified to be potential cocatalyst candidates for photocatalytic H₂ evolution. However, their cocatalytic activities are limited by the scarce number of unsaturated Se atoms and their weak bonding with adsorbed hydrogen atoms (Se–Hₐdₛ). Herein, a versatile tactic of unsaturated selenium-enrichment regulation is developed, which can not only increase the activ ...
activesites, etc ; architecture; batteries; carbon; chemical communication; ions; sodium; Show all 7 Subjects
Abstract:
... Hierarchical pores with accessible active sites in carbon are highly desired for enhancing sodium storage in sodium ion batteries (SIBs). However, it is still challenging to construct such materials with tunable architectures. Herein, a sponge-like 3D hierarchical porous Fe-doped carbon (Fe@NCS) was successfully assembled from an energetic framework. The continuous distribution of micro/meso/macro ...
activesites, etc ; ambient temperature; nanopores; nanosilver; oxidation; silver; sodium chloride; Show all 7 Subjects
Abstract:
... The potential of three-dimensional surface-enhanced Raman scattering (3D SERS) imaging has successfully been extended to investigate the transformation mechanism of metal contents in the galvanic replacement reaction of 3D nanoporous silver microstructures (AgMSs). The galvanic replacement reaction between AgMSs and Au³⁺ occurs in a saturated sodium chloride solution at room temperature. The galva ...
activesites, etc ; catalysts; catalytic activity; harvesting; journals; organometallic compounds; polymers; Show all 7 Subjects
Abstract:
... Photoswitchable catalysts are becoming attractive materials for catalytic applications because of their favorable characteristics, such as customizable catalytic activity and particularly possible recyclability, as well as the unique advantages of light stimulation, such as low cost, good harvesting, non-toxicity and excellent stability. In this mini-review article, we focus primarily on azobenzen ...
activesites, etc ; DNA; Escherichia coli; bioactive properties; energy; flavonoids; ligands; Show all 7 Subjects
Abstract:
... In this study, the SAPT (DFT) method is used to determine the components of the electronic interaction energies (electrostatic (Eₑₗₑ), exchange (Eₑₓ), induction (Eᵢₙd), exchange-induction (Eₑₓ₋ᵢₙd), dispersion (Edᵢₛₚ), and exchange-dispersion (Eₑₓ₋dᵢₛₚ)) between the several selected flavonoids and the important residues of the active site of Escherichia coli DNA Gyr determined by molecular docking ...
activesites, etc ; carbon nitride; electron transfer; energy; graphene; hydrogen peroxide; photocatalysts; Show all 7 Subjects
Abstract:
... Artificial photoproduction of hydrogen peroxide (H₂O₂) from H₂O and O₂ by metal-free catalysts (e.g., graphitic carbon nitride) is regarded as an ultra-clean approach. Metal-free catalysts are often hindered by unpropitious rapid charge recombination and unfavorable selectivity. Herein, three carbon dots (CDs1 to CDs3) decorated modified-carbon nitride (CDs1-NCN, CDs2-NCN and CDs3-NCN) were design ...
activesites, etc ; catalysts; energy; feedstocks; gasoline; hydrogen; olefin; petroleum; porosity; zeolites; Show all 10 Subjects
Abstract:
... The direct conversion of crude oil to light olefins is considered one the cheapest and most reliable sources of petrochemical primary feedstocks. Unlike in the past when refineries operated to produce mainly transportation fuels, such as gasoline and diesel, many refineries worldwide are considering tandem production of both fuels and chemicals (particularly, light olefins). To achieve this, refin ...
activesites, etc ; biosensors; chitin; enzyme-linked immunosorbent assay; humans; luciferase; mutants; Show all 7 Subjects
Abstract:
... In this study, we applied a luciferase-fragment complementation assay for chitin detection. When luciferase-fragment fused chitin-binding proteins were mixed with chitin, the reconstituted luciferase became active. The recombinant chitin-binding domain (CBD) and a functionally modified catalytic domain (CatD) of human chitotriosidase were employed for this method. We designed the CatD mutant as a ...
activesites, etc ; enzymes; histidine; oxygen requirement; proteomics; pyridoxal phosphate; thiamin; yeasts; Show all 8 Subjects
Abstract:
... The eukaryotic thiamin pyrimidine synthase, THI5p, has been identified as a suicidal/single-turnover enzyme that catalyzes the conversion of its active site histidine and lysine-bound pyridoxal phosphate (PLP) to the thiamin pyrimidine (HMP-P). Here we identify the histidine and PLP fragments using bottom-up proteomics and LC-MS analysis. We also identify the active form of the iron cofactor and q ...
activesites, etc ; Lewis bases; early diagnosis; fluorescence; fluorescent dyes; mass spectrometry; thiols; Show all 7 Subjects
Abstract:
... Biological mercaptans, also known as biothiols, play their own roles in a number of important physiological processes, and the abnormal levels of biothiols are closely associated with a variety of diseases. Therefore, the selective detection of biothiols in biological systems is crucial for understanding their roles in physiological processes and the early diagnosis of diseases. In this article, w ...