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The pathophysiological underpinnings of critically disrupted brain connectomes resulting in coma are poorly understood. Inflammation is potentially an important but still undervalued factor. Here, we present a first-in-human prospective study using the 18-kDa translocator protein (TSPO) radioligand 18F-DPA714 for PET imaging to allow in vivo neuroimmune activation quantification in patients with coma (n = 17) following either anoxia or traumatic brain injuries in comparison with age- and sex-matched controls. Our findings yielded novel evidence of an early inflammatory component predominantly located within key cortical and subcortical brain structures that are putatively implicated in consciousness emergence and maintenance after severe brain injury (i.e. mesocircuit and frontoparietal networks). We observed that traumatic and anoxic patients with coma have distinct neuroimmune activation profiles, both in terms of intensity and spatial distribution. Finally, we demonstrated that both the total amount and specific distribution of PET-measurable neuroinflammation within the brain mesocircuit were associated with the patient's recovery potential. We suggest that our results can be developed for use both as a new neuroprognostication tool and as a promising biometric to guide future clinical trials targeting glial activity very early after severe brain injury.
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Lesões Encefálicas , Coma Pós-Traumatismo da Cabeça , Humanos , Coma/complicações , Coma Pós-Traumatismo da Cabeça/complicações , Estudos Prospectivos , Imageamento por Ressonância Magnética/métodos , Encéfalo/metabolismo , Lesões Encefálicas/complicações , Hipóxia/complicações , Receptores de GABA/metabolismoRESUMO
Age-related macular degeneration (AMD) is a complex degenerative disease of the retina. Dysfunction of the retinal pigment epithelium (RPE) occurs in early stages of AMD, and progressive RPE atrophy leads to photoreceptor death and visual impairments that ultimately manifest as geographic atrophy (GA), one of the late-stage forms of AMD. AMD is caused by a combination of risk factors including aging, lifestyle choices, and genetic predisposition. A gene variant in the complement factor H gene (CFH) that leads to the Y402H polymorphism in the factor H protein (FH) confers the second highest risk for the development and progression of AMD. FH is a major negative regulator of the alternative pathway of the complement system, and the FH Y402H variant leads to increased complement activation, which is detectable in AMD patients. For this reason, various therapeutic approaches targeting the complement system have been developed, however, so far with very limited or no efficacy. Interestingly, recent studies suggest roles for FH beyond complement regulation. Here, we will discuss the noncanonical functions of FH in RPE cells and highlight the potential implications of those functions for future therapeutic approaches.
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Fator H do Complemento , Degeneração Macular , Humanos , Fator H do Complemento/genética , Fator H do Complemento/metabolismo , Epitélio Pigmentado da Retina , Degeneração Macular/genética , Degeneração Macular/metabolismo , Ativação do Complemento/genética , Predisposição Genética para DoençaRESUMO
SrVO3 (SVO) is a prospective candidate to replace the conventional indium tin oxide (ITO) among the new generation of transparent conducting oxide (TCO) materials. In this study, the structural, electrical, and optical properties of SVO thin films, both epitaxial and polycrystalline, are determined during and after heat treatments in the 150-250 °C range and under ambient environment in order to explore the chemical stability of this material. The use of these relatively low temperatures speeds up the natural aging of the films and allows following the evolution of their related properties. The combination of techniques rather sensitive to the film surface and of techniques sampling the film volume will emphasize the presence of a surface oxidation evolving in time at low annealing temperatures, whereas the perovskite phase is destroyed throughout the film for treatments above 200 °C. The present study is designed to understand the thermal degradation and long-term stability issues of vanadate-based TCOs and to identify technologically viable solutions for the application of this group as new TCOs.
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Atopic dermatitis (AD) is a common inflammatory skin disorder characterized by a heterogeneous and fluctuating disease course. To obtain a detailed molecular understanding of both the temporal and spatial variation in AD, we conducted a longitudinal case-control study, in which we followed a population, the GENAD (Gentofte AD) cohort, of mild-to-moderate patients with AD and matched healthy controls for more than a year. By the use of 1.5 mm minipunch biopsies, we obtained 393 samples from lesional, nonlesional, and healthy skin from multiple anatomical regions at different time points for transcriptomic profiling. We observed that the skin transcriptome was remarkably stable over time, with the largest variation being because of disease, individual, and skin site. Numerous AD-specific, differentially expressed genes were identified and indicated a disrupted skin barrier and activated immune response as the main features of AD. We also identified potentially novel targets in AD, including IL-37, MAML1, and several long noncoding RNAs. We envisage that the application of small biopsies, such as those introduced in this study, combined with omics technologies, will enable future skin research, in which multiple sampling from the same individual will give a more detailed, dynamic picture of how a disease fluctuates in time and space.
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Dermatite Atópica , Humanos , Dermatite Atópica/patologia , Transcriptoma , Estudos de Casos e Controles , Pele/patologia , Biópsia , Proteínas de Ligação a DNA/genética , Fatores de Transcrição/genéticaRESUMO
The 2023 International African Swine Fever Workshop (IASFW) took place in Beijing, China, on 18-20 September 2023. It was jointly organized by the U.S.-China Center for Animal Health (USCCAH) at Kansas State University (KSU) and the Chinese Veterinary Drug Association (CVDA) and sponsored by the United States Department of Agriculture Foreign Agricultural Service (USDA-FAS), Harbin Veterinary Research Institute, and Zoetis Inc. The objective of this workshop was to provide a platform for ASF researchers around the world to unite and share their knowledge and expertise on ASF control and prevention. A total of 24 outstanding ASF research scientists and experts from 10 countries attended this meeting. The workshop included presentations on current ASF research, opportunities for scientific collaboration, and discussions of lessons and experiences learned from China/Asia, Africa, and Europe. This article summarizes the meeting highlights and presents some critical issues that need to be addressed for ASF control and prevention in the future.
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Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Animais , Humanos , Febre Suína Africana/prevenção & controle , Febre Suína Africana/epidemiologia , Ásia , China/epidemiologia , África/epidemiologia , Sus scrofa , Surtos de Doenças/veterináriaRESUMO
Hydride transfer reactions involving 1,4-dihydropyridines play a central role in bioorganic chemistry as they represent an important share of redox metabolism. For this class of reactions, direct hydride transfer is the commonly accepted mechanism; however, an Alder-Ene-like pathway has been proposed as a plausible alternative. The reaction between 1,4-ditrimethylsilyl-1,4-dihydropyridine and α,ß-unsaturated nitriles is a solid candidate for this latter pathway. In this work, we perform high level ab initio and density functional theory computations to characterize the mechanism of this reaction, taking into account diverse reaction paths, and evaluating the effect of solvent polarity and variations in the chemical structure. Our analysis explains the stereochemical aspects of the reaction, characterizing the up to now unresolved spatial configurations of the predominant products, and may contribute to the understanding of enzymatic reactions involving NADP(H). The reactions are found to proceed in an asynchronous fashion, with transition states that display significant aromatic features. With this observation in mind, Alder-Ene and direct hydride transfer pathways can be understood as two extremes of a continuous mechanistic spectrum for this kind of reaction, with the analyzed systems located approximately equidistant from both ends.
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Di-Hidropiridinas , Nitrilas , Nitrilas/química , Di-Hidropiridinas/química , OxirreduçãoRESUMO
Enoyl-CoA carboxylases/reductases (ECRs) are some of the most efficient CO2-fixing enzymes described to date. However, the molecular mechanisms underlying the extraordinary catalytic activity of ECRs on the level of the protein assembly remain elusive. Here we used a combination of ambient-temperature X-ray free electron laser (XFEL) and cryogenic synchrotron experiments to study the structural organization of the ECR from Kitasatospora setae. The K. setae ECR is a homotetramer that differentiates into a pair of dimers of open- and closed-form subunits in the catalytically active state. Using molecular dynamics simulations and structure-based mutagenesis, we show that catalysis is synchronized in the K. setae ECR across the pair of dimers. This conformational coupling of catalytic domains is conferred by individual amino acids to achieve high CO2-fixation rates. Our results provide unprecedented insights into the dynamic organization and synchronized inter- and intrasubunit communications of this remarkably efficient CO2-fixing enzyme during catalysis.
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Tape stripping is a non-invasive skin sampling technique, which has recently gained use for the study of the transcriptome of atopic dermatitis (AD), a common inflammatory skin disorder characterized by a defective epidermal barrier and perturbated immune response. Here, we performed BRB-seq-a low cost, multiplex-based, transcriptomic profiling technique-on tape-stripped skin from 30 AD patients and 30 healthy controls to evaluate the methods' ability to assess the epidermal AD transcriptome. An AD signature consisting of 91 differentially expressed genes, specific for skin barrier and inflammatory response, was identified. The gene expression in the outermost layers, stratum corneum and stratum granulosum, of the skin showed highest correlation between tape-stripped skin and matched full-thickness punch biopsies. However, we observed that low and highly variable transcript counts, probably due to low RNA yield and RNA degradation in the tape-stripped skin samples, were a limiting factor for epidermal transcriptome profiling as compared to punch biopsies. We conclude that deep BRB-seq of tape-stripped skin is needed to counteract large between-sample RNA yield variation and highly zero-inflated data in order to apply this protocol for population-wide screening of the epidermal transcriptome in inflammatory skin diseases.
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Dermatite Atópica , Dermatite Atópica/metabolismo , Epiderme/metabolismo , Humanos , RNA/metabolismo , Pele/metabolismo , TranscriptomaRESUMO
Glucocorticoids (GCs) are commonly used topical treatments for skin diseases but are associated with both local and systemic side effects. In this study, we describe a selective non-steroidal glucocorticoid receptor (GR) agonist for topical use, LEO 134310, which is rapidly deactivated in the blood resulting in low systemic exposure and a higher therapeutic index in the TPA-induced skin inflammation mouse model compared with betamethasone valerate (BMV) and clobetasol propionate (CP). Selectivity of LEO 134310 for GR was confirmed within a panel of nuclear receptors, including the mineralocorticoid receptor (MR), which has been associated with induction of skin atrophy. Topical treatment with LEO 134310 in minipigs did not result in any significant reduction in epidermal thickness in contrast to significant epidermal thinning induced by treatment with BMV and CP. Thus, the profile of LEO 134310 may potentially provide an effective and safer treatment option for skin diseases compared with currently used glucocorticoids.
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GlucocorticoidesRESUMO
We explored the time dependence of the nanoscale domain relaxation mechanism in epitaxial K0.5Na0.5NbO3 (KNN) thin films grown on La0.67Sr0.33MnO3/SrTiO3 (001) substrates over the thickness range 20-80 nm using scanning probe microscopy. Kelvin probe force microscopy (KFM) and piezoresponse force microscopy were performed on pulsed-laser-deposition-deposited KNN thin films for studying the time evolution of trapped charges and polarized domains, respectively. The KFM data show that the magnitude and retention time of the surface potential are the maxima for 80 nm-thick film and reduce with the reduction in the film thickness. The charging and discharging of the samples reveal the easier and stronger electron trapping compared to hole trapping. This result further indicates the asymmetry between retention of the pulse-voltage-induced upward and downward domains. Furthermore, the time evolution of these ferroelectric nanodomains are found to obey stretched exponential behavior. The relaxation time (T) has been found to increase with increase in thickness; however, the corresponding stretched exponent (ß) is reduced. Moreover, the written domain can retain for more than 2300 min in KNN thin films. An in-depth understanding of domain relaxation dynamics in Pb-free KNN thin films can bridge a path for future high-density memory applications.
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We have probed the structural and magnetic properties of PrVO3 (PVO) thin films grown on the (001)-, (110)-, and (111)-oriented SrTiO3 (STO) substrates. By changing the substrate orientation, the film out-of-plane orientation can be tuned to [110], [100]/[010], and [011]/[311], with different in-plane crystallographic variants. Accommodation of these variants on the different substrates implies different strain states, which have direct influence on the magnetic properties of PVO films. The magnetic moment of PVO films radically enhances from 0.4 µB/f.u. for STO(001) to 2.3 µB/f.u. for STO(111). While films on the (001)-oriented STO substrate display out-of-plane anisotropy, an in-plane anisotropy is observed for films grown on the (110)- and (111)-oriented STO substrates. In addition, a strong uniaxial magnetic anisotropy is also extracted for a partially relaxed film on the (110)-oriented STO substrate. Such findings can help oxide community for the better understanding of magnetic anisotropy in vanadate thin films, a subject that still suffer from significant lack of scientific investigations.
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Local reactivity descriptors such as atom-condensed Fukui functions are promising computational tools to study chemical reactivity at specific sites within a molecule. Their applications have been mainly focused on isolated molecules in their most stable conformation without considering the effects of the surroundings. Here we propose to combine quantum mechanics/molecular mechanics Born-Oppenheimer molecular dynamics simulations to obtain the microstates (configurations) of a molecular system using different representations of the molecular environment and calculate Boltzmann-weighted atom-condensed local reactivity descriptors based on conceptual density functional theory. Our approach takes the conformational fluctuations of the molecular system and the polarization of its electron density by the environment into account, allowing us to analyze the effect of the molecular environment on reactivity. In this contribution, we apply the method mentioned above to the catalytic fixation of carbon dioxide by crotonyl-CoA carboxylase/reductase and study if the enzyme alters the reactivity of its substrate compared with an aqueous solution. Our main result is that the protein environment activates the substrate by the elimination of solute-solvent hydrogen bonds from aqueous solution in the two elementary steps of the reaction mechanism: the nucleophilic attack of a hydride anion from NADPH on the α,ß-unsaturated thioester and the electrophilic attack of carbon dioxide on the formed enolate species.
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Dióxido de Carbono/química , Carbono-Carbono Ligases/química , Acil Coenzima A/química , Teoria da Densidade Funcional , Ligação de Hidrogênio , Modelos Químicos , Simulação de Dinâmica Molecular , NADP/químicaRESUMO
BACKGROUND: IL-17 antagonists induce impressive clinical benefits in psoriasis, but it is unknown to what extent cellular and molecular psoriasis characteristics are suppressed by a clinically relevant dose/schedule of any IL-17-receptor antagonist. OBJECTIVE: We sought to examine the effects of the IL-17 receptor-A antagonist brodalumab, on clinical and molecular psoriasis features over a 12-week period. METHODS: A subset of patients (n = 116) enrolled in 3 phase-3 randomized clinical trials (AMAGINE -1 [Efficacy, Safety, and Withdrawal and Retreatment With Brodalumab in Moderate to Severe Plaque Psoriasis Subjects], -2 [P3 Study Brodalumab in Treatment of Moderate to Severe Plaque Psoriasis], and -3 [Efficacy and Safety of Brodalumab Compared With Placebo and Ustekinumab in Moderate to Severe Plaque Psoriasis in Subjects]) participated in a mechanistic substudy where punch biopsies were collected (lesional and nonlesional skin) between baseline and 12 weeks. This cohort included moderate-to-severe psoriasis patients treated with 140 mg (n = 46), 210 mg (n = 41) brodalumab, or placebo (n = 29). Key epidermal psoriatic features, including T-cell and dendritic cell subsets, were examined using immunohistochemistry. Treatment-induced changes in lesional skin gene expression profiles were evaluated using Affymetrix arrays. RESULTS: IL-17 receptor-A antagonism caused extensive improvements in clinical, histologic, and transcriptomic features of psoriasis. Cellular infiltrates (CD3+, CD8+, CD11c+, CD163+), markers of keratinocyte proliferation (Ki67+, KRT16), and inflammatory cytokines (IL-17A/C/F, IL-23A, IL-12B) decreased progressively, reaching close to nonlesional levels, paralleled by decreases in epidermal thickness. Psoriasis transcriptome gene expression improved â¼85% to 95% in responders whose psoriasis area severity index improved by 75% from baseline by week 12 (n = 63), compared with â¼30% to 65% in nonresponders (n = 12), while the residual disease genomic profile was 10% of the psoriasis transcriptome, which is less than for earlier generation drugs. IL-17-dependent gene expression, including keratinocyte genes, improved earlier and more extensively following brodalumab treatment compared with ustekinumab treatment (anti-IL-23/-IL-12). CONCLUSIONS: The clinically approved dose and schedule for brodalumab leads to nearly complete resolution of clinical, histologic, and transcriptomic features of psoriasis. Evidently, IL-17-induced release of keratinocyte-derived inflammatory mediators is a key driver of psoriasis pathogenesis.
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Anticorpos Monoclonais Humanizados/uso terapêutico , Fármacos Dermatológicos/uso terapêutico , Psoríase/tratamento farmacológico , Transcriptoma/efeitos dos fármacos , Adulto , Idoso , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/patologia , Receptores de Interleucina-17/antagonistas & inibidoresRESUMO
INTRODUCTION: Testicular microlithiasis (TM) is an uncommon finding in general male population. These calcifications are reported by testicular ultrasound performed by some testicular pathology and constitute an incidental finding. The presence of TM is regularly associated to testicular neoplasms. OBJECTIVES: To investigate the relationship between clinical and demographic factors, comorbidities and tumor biomarkers, and the presence or absence of microlithiasis in patients with testicular cancer. MATERIAL AND METHODS: A retrospective study including a total of 66 patients diagnosed with testicular carcinoma from 2012 to 2017 in a hospital in Northeastern Mexico. The total of patients was divided into 2 groups according to the presence or absence of MT and the clinical features of these were analyzed. RESULTS: There was a general prevalence of TM of 31.8%. The main tumor found in the pathology reports corresponded to the non seminomatous germ cells tumor (54.4%). The incidence of metastasis to organs was of 27.3%. No statistically significant differences were found when comparing the variables of interest in the group with and without MT. A relationship was found between the elevation of alpha-fetoprotein and non-seminomatous tumors compared to seminomatous tumors (PY=Y.003). CONCLUSIONS: According to the results obtained, it can be suggested that TM is a clinical finding that is not related to the prognosis of the disease or any of the comorbidities and clinical data analyzed in our study.
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Cálculos/diagnóstico , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Doenças Testiculares/diagnóstico , Neoplasias Testiculares/diagnóstico , Adulto , Biomarcadores Tumorais/metabolismo , Cálculos/epidemiologia , Cálculos/patologia , Estudos Transversais , Humanos , Incidência , Masculino , Metástase Neoplásica , Neoplasias Embrionárias de Células Germinativas/patologia , Prevalência , Prognóstico , Estudos Retrospectivos , Doenças Testiculares/epidemiologia , Doenças Testiculares/patologia , Neoplasias Testiculares/patologia , Ultrassonografia , Adulto Jovem , alfa-Fetoproteínas/metabolismoRESUMO
New paradigms are required in microelectronics when the transistor is in its downscaling limit and integration of materials presenting functional properties not available in classical silicon is one of the promising alternatives. Here, we demonstrate the possibility to grow La0.67Sr0.33MnO3 (LSMO) functional materials on amorphous substrates with properties close to films grown on single-crystalline substrates using a two-dimensional seed layer. X-ray diffraction and electron backscatter diffraction mapping demonstrate that the Ca2Nb3O10- nanosheet (NS) layer induces epitaxial stabilization of LSMO films with a strong out-of-plane (001) texture, whereas the growth of LSMO films on uncoated glass substrates exhibits a nontextured polycrystalline phase. The magnetic properties of LSMO films deposited on NS are similar to those of the LSMO grown on SrTiO3 single-crystal substrates in the same conditions (which is used as a reference in this work). Moreover, transport measurements take advantages of the texture and polycrystalline properties to induce low-field magnetoresistance at low temperature and also a high value of 40% magnetoresistance from 10 to 300 K, making it interesting for sensor applications. Therefore, the NS seed layer offers new perspectives for the integration of functional materials grown at moderate temperatures on any substrate, which will be the key for the development of oxitronics.
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Developing new carbon dioxide (CO2) fixing enzymes is a prerequisite to create new biocatalysts for diverse applications in chemistry, biotechnology and synthetic biology. Here we used bioinformatics to identify a "sleeping carboxylase function" in the superfamily of medium-chain dehydrogenases/reductases (MDR), i.e. enzymes that possess a low carboxylation side activity next to their original enzyme reaction. We show that propionyl-CoA synthase from Erythrobacter sp. NAP1, as well as an acrylyl-CoA reductase from Nitrosopumilus maritimus possess carboxylation yields of 3 ± 1 and 4.5 ± 0.9%. We use rational design to engineer these enzymes further into carboxylases by increasing interactions of the proteins with CO2 and suppressing diffusion of water to the active site. The engineered carboxylases show improved CO2-binding and kinetic parameters comparable to naturally existing CO2-fixing enzymes. Our results provide a strategy to develop novel CO2-fixing enzymes and shed light on the emergence of natural carboxylases during evolution.
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Carboxiliases/química , Oxirredutases/química , Archaea/enzimologia , Proteínas Arqueais/química , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Ciclo do Carbono , Dióxido de Carbono/química , Dióxido de Carbono/metabolismo , Carboxiliases/genética , Carboxiliases/metabolismo , Domínio Catalítico/genética , Cinética , Simulação de Dinâmica Molecular , Mutagênese Sítio-Dirigida , Oxirredutases/genética , Oxirredutases/metabolismo , Sphingomonadaceae/enzimologia , Água/química , Água/metabolismoRESUMO
Carboxylases are biocatalysts that capture and convert carbon dioxide (CO2) under mild conditions and atmospheric concentrations at a scale of more than 400 Gt annually. However, how these enzymes bind and control the gaseous CO2 molecule during catalysis is only poorly understood. One of the most efficient classes of carboxylating enzymes are enoyl-CoA carboxylases/reductases (Ecrs), which outcompete the plant enzyme RuBisCO in catalytic efficiency and fidelity by more than an order of magnitude. Here we investigated the interactions of CO2 within the active site of Ecr from Kitasatospora setae Combining experimental biochemistry, protein crystallography, and advanced computer simulations we show that 4 amino acids, N81, F170, E171, and H365, are required to create a highly efficient CO2-fixing enzyme. Together, these 4 residues anchor and position the CO2 molecule for the attack by a reactive enolate created during the catalytic cycle. Notably, a highly ordered water molecule plays an important role in an active site that is otherwise carefully shielded from water, which is detrimental to CO2 fixation. Altogether, our study reveals unprecedented molecular details of selective CO2 binding and C-C-bond formation during the catalytic cycle of nature's most efficient CO2-fixing enzyme. This knowledge provides the basis for the future development of catalytic frameworks for the capture and conversion of CO2 in biology and chemistry.
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Aminoácidos/química , Dióxido de Carbono/química , Ácidos Graxos Dessaturases/química , Modelos Moleculares , Aminoácidos/genética , Aminoácidos/metabolismo , Dióxido de Carbono/metabolismo , Proteínas de Transporte/química , Catálise , Domínio Catalítico/genética , Enzimas/química , Ácidos Graxos Dessaturases/metabolismo , Streptomycetaceae/química , Streptomycetaceae/enzimologiaRESUMO
Carboxylation reactions represent a very special class of chemical reactions that is characterized by the presence of a carbon dioxide (CO2 ) molecule as reactive species within its global chemical equation. These reactions work as fundamental gear to accomplish the CO2 fixation and thus to build up more complex molecules through different technological and biochemical processes. In this context, a correct description of the CO2 electronic structure turns out to be crucial to study the chemical and electronic properties associated with this kind of reactions. Here, a systematic study of CO2 electronic structure and its contribution to different carboxylation reaction electronic energies has been carried out by means of several high-level ab initio post-Hartree Fock (post-HF) and density functional theory (DFT) calculations for a set of biochemistry and inorganic systems. We have found that for a correct description of the CO2 electronic correlation energy it is necessary to include post-CCSD(T) contributions (beyond the gold standard). These high-order excitations are required to properly describe the interactions of the four π-electrons associated with the two degenerated π-molecular orbitals of the CO2 molecule. Likewise, our results show that in some reactions it is possible to obtain accurate reaction electronic energy values with computationally less demanding methods when the error in the electronic correlation energy compensates between reactants and products. Furthermore, the provided post-HF reference values allowed to validating different DFT exchange-correlation functionals combined with different basis sets for chemical reactions that are relevant in biochemical CO2 fixing enzymes. © 2019 Wiley Periodicals, Inc.