Listar QFA_Articles por título
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Protein Isotope Effects in Dihydrofolate Reductase From Geobacillus stearothermophilus Show Entropic–Enthalpic Compensatory Effects on the Rate Constant
American Chemical Society (2014)Catalysis by dihydrofolate reductase from the moderately thermophilic bacterium Geobacillus stearothermophilus (BsDHFR) was investigated by isotope substitution of the enzyme. The enzyme kinetic isotope effect for hydride ... -
Proton transport catalysis in intramolecular rearrangements: A density functional theory study
Elsevier (2008)Experimental observations show that for the gas phase isomerization of protonated molecules, a third body can transport a proton from a high-energy site to a lower energy-site of the substrate, thereby catalyzing the ... -
Pure and Ni2O3-decorated CeO2 nanoparticles applied as CO gas sensor: Experimental and theoretical insights
Elsevier (2022-01-29)In the present work, the structural, morphological and electrical properties of CeO2 nanoparticles with spherical and rod-like morphologies and rods decorated with Ni2O3 were investigated. Morphological, structural and ... -
PVC-SiO2-Ag composite as a powerful biocide and anti-SARS-CoV-2 material
Springer (2021-08-31)The ongoing COVID-19 pandemic has pushed scientists and technologists to find novel strategies to develop new materials to prevent the transmission, spread, and entry of pathogens into the human body. In this report, the ... -
QM/MM Calculations Suggest a Novel Intermediate Following the Proton Abstraction Catalyzed by Thymidylate Synthase
American Chemical Society (2013-03-07)The cleavage of covalent C–H bonds is one of the most energetically demanding, yet biologically essential, chemical transformations. Two C–H bond cleavages are involved in the reaction catalyzed by thymidylate synthase ... -
QM/MM kinetic isotope effects for chloromethane hydrolysis in water
John Wiley & Sons (2013)Computational simulations for chloromethane hydrolysis have been performed using hybrid quantum-mechanical/molecular-mechanical methods with explicit solvation by large numbers of water molecules. In the first part of the ... -
QM/MM modeling of the hydroxylation of the androstenedione substrate catalyzed by cytochrome P450 aromatase (CYP19A1)
Wiley (2015-09)CYP19A1 aromatase is a member of the Cytochrome P450 family of hemeproteins, and is the enzyme responsible for the final step of the androgens conversion into the corresponding estrogens, via a three-step oxidative process. ... -
QM/MM simulations for methyl transfer in solution and catalysed by COMT: ensemble-averaging of kinetic isotope effects
Royal Society of Chemistry (2008)Sampling of structures from QM/MM molecular dynamics reveals distinct families of reactant-state conformers and yields kinetic isotope effects for reactions in enzyme active sites and in solution, averaged over thermal ... -
QM/MM Study of L-Lactate Oxidation by Flavocytochrome b2
Royal Society of Chemistry (2016-05-18)In this work, we have performed molecular dynamics simulations using a hybrid Quantum Mechanics/Molecular Mechanics (QM/MM) scheme to study the mechanism of L-lactate oxidation by flavocytochrome b2 (Fcb2). Our results ... -
QM/MM study of thymidylate synthase: enzymatic motions and the temperature dependence of the rate limiting step
American Chemical Society (2009)Thymidylate synthase (TS) is an enzyme that catalyzes a complex cascade of reactions. A theoretical study of the reduction of an exocyclic methylene intermediate by hydride transfer from the 6S position of 5,6,7,8-tetrahydrofolate ... -
QM/MM Theoretical Studies of a de Novo Retro-Aldolase Design
American Chemical Society (2019)The design of innovative enzymes is a standing goal to obtain original specific catalysts to work under mild conditions of temperature and pressure. Attempts to get artificial enzymes become particularly difficult when the ... -
QMCube (QM3): An all‐purpose suite for multiscale QM/MM calculations
Wiley (2020-12-18)QMCube (QM3) is a suite written in the Python programming language, initially focused on multiscale QM/MM simulations of biological systems, but open enough to address other kinds of problems. It allows the user to combine ... -
Quantification of Melamine in Drinking Water and Wastewater by Micellar Liquid Chromatography
AOAC International (2013)Because of the large potential health impact caused by deliberate contamination with the synthetic chemical melamine of different products for human and animal consumption, the World Health Organization and the Food and ... -
Quantification of rifampicin and rifabutin in plasma of tuberculosis patients by micellar liquid chromatography
Elsevier (2020)A Micellar Liquid Chromatographic method is described to determine Rifampicin and Rifabutin in plasma from Tuberculosis patients. Samples were diluted in mobile phase and then directly injected, avoiding long and tedious ... -
Quantification of Tamoxifen in Pharmaceutical Formulations Using Micellar Liquid Chromatography
Japan Society for Analytical Chemistry (2014)This paper describes a micellar liquid chromatographic method used to analyze tamoxifen (TAMO) in pharmaceutical formulations, while focusing in its interesting features. Solid samples were solved in a micellar solution, ... -
Quantum chemical topological analysis of hydrogen bonding in HX…HX and CH3X…HX dimers (X = Br, Cl, F)
Taylor & Francis (2015)We present a systematic investigation of the nature and strength of the hydrogen bonding in HX···HX and CH3X…HX (X = Br, Cl and F) dimers using ab initio MP2/aug-cc-pVTZ calculations in the framework of the quantum theory ... -
Quantum mechanical modeling of excited electronic states and their relationship to cathodoluminescence of BaZrO3
American Institute of Physics (AIP Publishing LLC) (2013)First-principles calculations set the comprehension over performance of novel cathodoluminescence (CL) properties of BaZrO3 prepared through microwave-assisted hydrothermal. Ground (singlet, s*) and excited (singlet s** ... -
Quantum Mechanical/Molecular Mechanical Molecular Dynamics Simulation of Wild-Type and Seven Mutants of CpNagJ in Complex with PUGNAc
American Chemical Society (2010)The enzyme O-glycoprotein 2-acetamino-2-deoxy-β-d-glucopyranosidase (O-GlcNAcase) is responsible for the removal of N-acetylglucosamine moieties from 2-acetamido-2-deoxy-β-d-glucopyranose (O-GlcNAc) residues of serine/threonine ... -
Quantum Mechanics Insight into the Microwave Nucleation of SrTiO3 Nanospheres
American Chemical Society (2012)An extensive investigation of strontium titanate, SrTiO3 (STO), nanospheres synthesized via a microwave-assisted hydrothermal (MAH) method has been conducted to gain a better insight into thermodynamic, kinetic, and reaction ... -
Quantum mechanics/molecular mechanics studies of the mechanism of cysteine protease inhibition by peptidyl-2,3-epoxyketones
Royal Society of Chemistry (2017)Cysteine proteases are the most abundant proteases in parasitic protozoa and they are essential enzymes to the life cycle of several of them, thus becoming attractive therapeutic targets for the development of new ...