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In this review, we describe speculative ideas and early stage research concerning the flow of genetic information from the nuclear residence of genes to the disparate, cytoplasmic sites of protein synthesis. We propose that this process of information transfer is meticulously guided by transient structures formed from protein segments of low sequence complexity/intrinsic disorder. These low complexity domains are ubiquitously associated with regulatory proteins that control gene expression and RNA biogenesis, but they are also found in the central channel of nuclear pores, the nexus points of intermediate filament assembly, and the locations of action of other well-studied cellular proteins and pathways. Upon being organized into localized cellular positions via mechanisms utilizing properly folded protein domains, thereby facilitating elevated local concentration, certain low complexity domains adopt cross-ß interactions that are both structurally specific and labile to disassembly. These weakly tethered assemblies, we propose, are built to relay the passage of genetic information from one site to another within a cell, ensuring that the process is of extreme fidelity.
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Proteínas Intrinsicamente Desordenadas/genética , Proteínas Intrinsicamente Desordenadas/metabolismo , Modelos Biológicos , Animais , Grânulos Citoplasmáticos/genética , Grânulos Citoplasmáticos/metabolismo , Expressão Gênica , Transtornos Heredodegenerativos do Sistema Nervoso/genética , Transtornos Heredodegenerativos do Sistema Nervoso/metabolismo , Humanos , Hidrogéis , Proteínas Intrinsicamente Desordenadas/química , Modelos Moleculares , Mutação , Domínios e Motivos de Interação entre Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína FUS de Ligação a RNA/química , Proteína FUS de Ligação a RNA/genética , Proteína FUS de Ligação a RNA/metabolismoRESUMO
BACKGROUND: Renal denervation (RDN) has demonstrated clinically relevant reductions in blood pressure (BP) among individuals with uncontrolled hypertension despite lifestyle intervention and medications. The safety and effectiveness of alcohol-mediated RDN have not been formally studied in this indication. METHODS: TARGET BP I is a prospective, international, sham-controlled, randomized, patient- and assessor-blinded trial investigating the safety and efficacy of alcohol-mediated RDN. Patients with office systolic BP (SBP) ≥150 and ≤180 mm Hg, office diastolic BP ≥90 mm Hg, and mean 24-hour ambulatory SBP ≥135 and ≤170 mm Hg despite prescription of 2 to 5 antihypertensive medications were enrolled. The primary end point was the baseline-adjusted change in mean 24-hour ambulatory SBP 3 months after the procedure. Secondary end points included mean between-group differences in office and ambulatory BP at additional time points. RESULTS: Among 301 patients randomized 1:1 to RDN or sham control, RDN was associated with a significant reduction in 24-hour ambulatory SBP at 3 months (mean±SD, -10.0±14.2 mm Hg versus -6.8±12.1 mm Hg; treatment difference, -3.2 mm Hg [95% CI, -6.3 to 0.0]; P=0.0487). Subgroup analysis of the primary end point revealed no significant interaction across predefined subgroups. At 3 months, the mean change in office SBP was -12.7±18.3 and -9.7±17.3 mm Hg (difference, -3.0 [95% CI, -7.0 to 1.0]; P=0.173) for RDN and sham, respectively. No significant differences in ambulatory or office diastolic BP were observed. Adverse safety events through 6 months were uncommon, with one instance of accessory renal artery dissection in the RDN group (0.7%). No significant between-group differences in medication changes or patient adherence were identified. CONCLUSIONS: Alcohol-mediated RDN was associated with a modest but statistically significant reduction in 24-hour ambulatory SBP compared with sham control. No significant differences between groups in office BP or 6-month major adverse events were observed. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02910414.
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Anti-Hipertensivos , Pressão Sanguínea , Hipertensão , Rim , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Anti-Hipertensivos/uso terapêutico , Hipertensão/fisiopatologia , Hipertensão/tratamento farmacológico , Hipertensão/cirurgia , Pressão Sanguínea/efeitos dos fármacos , Idoso , Rim/inervação , Estudos Prospectivos , Etanol/efeitos adversos , Etanol/administração & dosagem , Etanol/farmacologia , Resultado do Tratamento , Monitorização Ambulatorial da Pressão Arterial , Simpatectomia/efeitos adversos , Simpatectomia/métodos , Artéria Renal/inervaçãoRESUMO
Malaria tropica, caused by the parasite Plasmodium falciparum (P. falciparum), remains one of the greatest public health burdens for humankind. Due to its pivotal role in parasite survival, the energy metabolism of P. falciparum is an interesting target for drug design. To this end, analysis of the central metabolite adenosine triphosphate (ATP) is of great interest. So far, only cell-disruptive or intensiometric ATP assays have been available in this system, with various drawbacks for mechanistic interpretation and partly inconsistent results. To address this, we have established fluorescent probes, based on Förster resonance energy transfer (FRET) and known as ATeam, for use in blood-stage parasites. ATeams are capable of measuring MgATP2- levels in a ratiometric manner, thereby facilitating in cellulo measurements of ATP dynamics in real-time using fluorescence microscopy and plate reader detection and overcoming many of the obstacles of established ATP analysis methods. Additionally, we established a superfolder variant of the ratiometric pH sensor pHluorin (sfpHluorin) in P. falciparum to monitor pH homeostasis and control for pH fluctuations, which may affect ATeam measurements. We characterized recombinant ATeam and sfpHluorin protein in vitro and stably integrated the sensors into the genome of the P. falciparum NF54attB cell line. Using these new tools, we found distinct sensor response patterns caused by several different drug classes. Arylamino alcohols increased and redox cyclers decreased ATP; doxycycline caused first-cycle cytosol alkalization; and 4-aminoquinolines caused aberrant proteolysis. Our results open up a completely new perspective on drugs' mode of action, with possible implications for target identification and drug development.
Assuntos
Trifosfato de Adenosina , Antimaláricos , Transferência Ressonante de Energia de Fluorescência , Plasmodium falciparum , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/metabolismo , Plasmodium falciparum/genética , Trifosfato de Adenosina/metabolismo , Antimaláricos/farmacologia , Transferência Ressonante de Energia de Fluorescência/métodos , Corantes Fluorescentes/química , Humanos , Quinina/farmacologia , Doxiciclina/farmacologia , Artemisininas/farmacologia , Cloroquina/farmacologia , Concentração de Íons de HidrogênioRESUMO
Electroredox of organics provides a promising and green approach to producing value-added chemicals. However, it remains a grand challenge to achieve high selectivity of desired products simultaneously at two electrodes, especially for non-isoelectronic transfer reactions. Here a porous heterostructure of Mo2C@Co-NC is successfully fabricated, where subnanometre ß-Mo2C clusters (<1 nm, ≈10 wt%) are confined inside porous Co, N-doped carbon using metalorganic frameworks. It is found that Co species not only promote the formation of ß-Mo2C but also can prevent it from oxidation by constructing the heterojunctions. As noted, the heterostructure achieves >96% yield and 92% Faradaic efficiency (FE) for aldehydes in anodic alcohol oxidation, as well as >99.9% yield and 96% FE for amines in cathodal nitrocompounds reduction in 1.0 M KOH. Precise control of the reaction kinetics of two half-reactions by the electronic interaction between ß-Mo2C and Co is a crucial adjective. Density functional theory (DFT) gives in-depth mechanistic insight into the high aldehyde selectivity. The work guides authors to reveal the electrooxidation nature of Mo2C at a subnanometer level. It is anticipated that the strategy will provide new insights into the design of highly effective bifunctional electrocatalysts for the coproduction of more complex fine chemicals.
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The reported chemoenzymatic strategy involves the employment of vinyl 3-(dimethylamino)propanoate as an irreversible acyl donor in a chromatography-free lipase-catalyzed kinetic resolution (KR) of racemic sec-alcohols. This biotransformation is achieved in a sequential manner using CAL-B to affect the kinetic resolution, followed by a simple acidic extractive work-up furnishing both KR products with excellent enantioselectivity (E>200; up to 98 % ee). The elaborated method eliminates a single-use silica gel chromatographic separation and significantly reduces organic solvent consumption to foster a more environmentally friendly chemical industry.
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Álcoois , Biocatálise , Lipase , Lipase/metabolismo , Lipase/química , Cinética , Álcoois/química , Álcoois/metabolismo , Estereoisomerismo , Propionatos/química , Propionatos/metabolismo , Compostos de Vinila/químicaRESUMO
Chiral tertiary alcohols are important organic compounds in science as well as in industry. However, their preparation in enantiomerically pure form is still a challenge due to their complex structure and steric hindrances compared with primary and secondary alcohols, so kinetic resolution could be an attractive approach. Lipase A from Candida antarctica (CAL-A) has been shown to catalyze the enantioselective esterification of various tertiary alcohols with excellent enantioselectivity but low activity. Here we report a mutagenesis study by rational design to improve CAL-A activity against tertiary alcohols. Single mutants of CAL-A were selected, expressed, immobilized and screened for esterification of the tertiary alcohol 1,2,3,4-tetrahydronaphthalene-1-ol. A double mutant V278S+S429G showed a 1.5-fold higher reaction rate than that of the wild type CAL-A, while maintaining excellent enantioselectivity.
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Chiral alcohols are not only important building blocks of various bioactive natural compounds and pharmaceuticals, but can serve as synthetic precursors for other valuable organic chemicals, thus the synthesis of these products is of great importance. Bio-catalysis represents one effective way to obtain these molecules, however, the weak stability and high cost of enzymes often hinder its broad application. In this work, we designed a biological nanoreactor by embedding alcohol dehydrogenase (ADH) and glucose dehydrogenase (GDH) in metal-organic-framework ZIF-8. The biocatalyst ADH&GDH@ZIF-8 could be applied to the asymmetric reduction of a series of ketones to give chiral alcohols in high yields (up to 99 %) and with excellent enantioselectivities (>99 %). In addition, the heterogeneous biocatalyst could be recycled and reused at least four times with slight activity decline. Moreover, E.â coli containing ADH and GDH was immobilized by ZIF-8 to form biocatalyst E.â coli@ZIF-8, which also exhibits good catalytic behaviours. Finally, the chiral alcohols are further converted to marketed drugs (R)-Fendiline, (S)-Rivastigmine and NPS R-568 respectively.
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Álcool Desidrogenase , Biocatálise , Enzimas Imobilizadas , Escherichia coli , Glucose 1-Desidrogenase , Cetonas , Estruturas Metalorgânicas , Álcool Desidrogenase/metabolismo , Álcool Desidrogenase/química , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/metabolismo , Cetonas/química , Cetonas/metabolismo , Enzimas Imobilizadas/metabolismo , Enzimas Imobilizadas/química , Escherichia coli/enzimologia , Escherichia coli/metabolismo , Glucose 1-Desidrogenase/metabolismo , Glucose 1-Desidrogenase/química , Oxirredução , EstereoisomerismoRESUMO
Valorization of microalgae into high-value products and drop-in chemicals can reduce our dependence on non-renewable fossil fuels in an environmentally sustainable way. Among the valuable products, medium-chain carboxylic acids (MCCAs) and alcohols are attractive building blocks as fuel precursors. However, the biosynthetic mechanisms of MCCAs and alcohols in anaerobic microalgae fermentation and the regulating role of pH on the microbial structure and metabolism interaction among different functional groups have never been documented. In this work, we systematically investigated the roles of pH (5, 7, and 10) on the production of MCCAs and alcohols in anaerobic microalgae fermentation. The gene-centric and genome-centric metagenomes were employed to uncover the dynamics and metabolic network of the key players in the microbial communities. The results indicated that the pH significantly changed the product spectrum. The maximum production rate of alcohol was obtained at pH 5, while pH 7 was more beneficial for MCCA production. Metagenomic analysis reveals that this differential performance under different pH is attributed to the transformation of microbial guild and metabolism regulated by pH. The composition of various functional groups for MCCA and alcohol production also varies at different pH levels. Finally, a metabolic network was proposed to reveal the microbial interactions at different pH levels and thus provide insights into bioconversion of microalgae to high-value biofuels.IMPORTANCECarboxylate platforms encompass a biosynthesis process involving a mixed and undefined culture, enabling the conversion of microalgae, rich in carbohydrates and protein, into valuable fuels and mitigating the risks associated with algae blooms. However, there is little known about the effects of pH on the metabolic pathways of chain elongation and alcohol production in anaerobic microalgae fermentation. Moreover, convoluted and interdependent microbial interactions encumber efforts to characterize how organics and electrons flow among microbiome members. In this work, we compared metabolic differences among three different pH levels (5, 7, and 10) in anaerobic microalgae fermentation. In addition, genome-centric metagenomic analysis was conducted to reveal the microbial interaction for medium-chain carboxylic acid and alcohol production.
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Ácidos Carboxílicos , Microalgas , Fermentação , Ácidos Carboxílicos/metabolismo , Microalgas/metabolismo , Anaerobiose , Etanol/metabolismo , Concentração de Íons de HidrogênioRESUMO
Atopic dermatitis (AD) is a composite disease presenting disruption of the skin permeability barrier (SPB) in the stratum corneum (SC). Recent evidence supports derangement of the sebaceous gland (SG) activity in the AD pathomechanisms. The objective of this study was to delineate profiles of both sebaceous and epidermal lipids and of aminoacids from SG-rich (SGR) and SG-poor (SGP) areas in AD. Both sebum and SC were sampled from SGR areas, while SC was sampled also from SGP areas in 54 adult patients with AD, consisting of 34 and 20 subjects, respectively with and without clinical involvement of face, and in 44 age and sex-matched controls. Skin biophysics were assessed in all sampling sites. Disruption of the SBP was found to be associated with dysregulated lipidome. Abundance of sapienate and lignocerate, representing, respectively, sebum and the SC type lipids, were decreased in sebum and SC from both SGR and SGP areas. Analogously, squalene was significantly diminished in AD, regardless the site. Extent of lipid derangement in SGR areas was correlated with the AD severity. The abundance of aminoacids in the SC from SGR areas was altered more than that determined in SGP areas. Several gender-related differences were found in both controls and AD subgroups. In conclusion, the SG activity was differently compromised in adult females and males with AD, in both SGR and SGP areas. In AD, alterations in the aminoacidome profiles were apparent in the SGR areas. Lipid signatures in association with aminoacidome and skin physical properties may serve the definition of phenotype clusters that associate with AD severity and gender.
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Dermatite Atópica , Masculino , Adulto , Feminino , Humanos , Sebo , Glândulas Sebáceas , Pele , LipídeosRESUMO
Every biological and physicochemical process occurring in a fluid phase depends on the diffusion coefficient (D) of the species in solution. In the present work, a model to describe and fit the behaviour of D ${D}$ as a function of structure and extensive thermodynamics parameters in binary solutions of linear chain organic molecules is developed. Supporting experimental and computational evidences for this model are obtained by measuring D ${D}$ for a series of n ${n}$ -alcohols through a novel surface plasmon resonance method and molecular dynamics simulations. This allows to propose a kind of combined analysis to explain the dependence of D ${D}$ on various thermodynamic and structural parameters. The results suggest that for small linear systems in the range from 0 to 200â g mol-1 and under the assumption that the diffusive activation energy is a linear function of mass, D ${D}$ is strictly dependent on the molecular shape and on the relative strength of the solute-solvent intermolecular forces represented by a parameter named R. The newly proposed approach can be utilized to characterize and monitor progressive changes in physicochemical properties for any investigated species upon increasing the dimension of the aggregate/molecule along a certain direction.
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The oxidation of alcohols to the corresponding carbonyl derivatives has been realized under photoelectrochemical conditions in the presence of tetrabutylammonium decatungstate (TBADT) as the homogeneous photocatalyst. The protocol can be applied to both primary and secondary, benzylic and aliphatic alcohols. The desired products are obtained selectively, skipping the need for purposely added chemical oxidants. An in-depth study of photoelectrochemical conditions revealed that the protocol works best under amperostatic conditions in an undivided electrochemical cell irradiated with a 390 nm LED lamp. The comparison with analogous electrochemical and chemical oxidant-promoted photocatalytic oxidations demonstrates the superior efficiency and selectivity of the hereby reported photoelectrochemical conditions.
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Here, we introduce a new class of titanocene catalysts for epoxide hydrosilylation that frustrates their hydridicity and thereby emphasizes their electron transfer reactivity. This unique attenuation of hydridicity is accomplished by introducing Lewis acidic silicon centers to the cyclopentadienyl ligands for an intramolecular coordination of the titanium-bound hydride. The superiority of our rationally designed catalysts over classic titanocenes with alkyl-substituted cyclopentadienyl ligands is demonstrated in the dramatically improved regioselectivity of the hydrosilylation of monosubstituted epoxides to primary alcohols.
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The preparation of enantioenriched diarylmethanol derivatives is described using nickel-catalyzed electrochemical cross-couplings between various alkyl/aryl aldehydes and aryl iodides. Performed in an electrochemical cell equipped with an iron anode and a nickel cathode, this electrocatalytic variant led to the scalemic targeted products in the presence of 2,2-bis((4R,5S)-4,5-diphenyl-4,5-dihydrooxazol-2-yl)acetonitrile (L2), as enantiopure cyano-bis(oxazoline) ligand. X-ray structure analysis of a pre-catalyst, for instance the [Ni(II)(L2)2] complex, with L2 as an anionic bisoxazolinate ligand, confirms the chemical formulation of one nickel surrounded by two ligands. The redox behavior of the new Ni complexes generated in situ was first assessed by cyclic voltammetry showing a redox wave at ca. -1.5 V that can be assigned to the two-electron reduction of the Ni(II) center to the Ni(0) state. Oxidative addition between the electrogenerated Ni(0) complex and aryl iodide was evidenced. An intense current was observed in presence of a mixture of the two substrates pertaining an electrocatalytic process. Interestingly, we found that the sacrificial iron anode plays a crucial role in the catalytic mechanism.
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Hydroxytrifluoroethyl and trifluoroacetyl groups are of utmost importance in biologically active compounds, but methods to tether these motifs to organic architectures have been limited. Typically, the preparation of these compounds relied on the use of strong bases or multistep routes. The renaissance of radical chemistry in photocatalytic, transition metal mediated, and hydrogen atom transfer (HAT) processes have allowed the installation of these medicinally relevant fluorinated motifs. This review provides an overview of the methods available for the direct synthesis of hydroxytrifluoroethyl- and trifluoroacetyl-derived compounds governed by single-electron transfer processes.
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Allylic alcohols are a privileged motif in natural product synthesis and new methods that access them in a stereoselective fashion are highly sought after. Toward this goal, we found that chiral acetonide-protected polyketide fragments performing the Hoppe-Matteson-Aggarwal rearrangement in the absence of sparteine with high yields and diastereoselectivities rendering this protocol a highly valuable alternative to the Nozaki-Hiyama-Takai-Kishi reaction. Various stereodyads and -triads were investigated to determine their substrate induction. The mostly strong inherent stereoinduction was attributed to a combination of steric and electronic effects.
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A new series of unsymmetrical phenyl tellurides derived from 2-N-(quinolin-8-yl) benzamide ligand has been synthesized in a practical manner by the copper-catalyzed method by using diaryl ditelluride and Mg as a reductant at room temperature. In order to augment the Lewis acidity of these newly formed unsymmetrical monotellurides, these have been transformed into corresponding unsymmetrical 2-N-(quinolin-8-yl)benzamide tellurium cations. Subsequently, these Lewis acidic tellurium cations were used as chalcogen bonding catalysts, enabling the synthesis of various substituted 1,2-dihydroquinolines by activating ketones with anilines under mild conditions. Moreover, the synthesized 2-N-(quinolin-8-yl)benzamide phenyl tellurium cation has also catalyzed the formation of ß-amino alcohols in high regioselectivity by effectively activating epoxides at room temperature. Mechanistic insight by 1 H and 19 F NMR study, electrostatic surface potential (ESP map), control reaction in which tellurium cation reacted explosively with epoxide, suggested that the enhanced Lewis acidity of tellurium center seems responsible for efficient catalytic activities under mild conditions enabling ß-amino alcohols with excellent regioselectivity and 1,2-dihydroquinolines with trifluoromethyl, nitro, and pyridylsubstitution, which were difficult to access.
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Chiral secondary alcohols, serving as essential structural motifs, hold significant potential for diverse applications. The exploration of effective synthetic strategies toward these compounds is both attractive and challenging. Herein, we present an asymmetric oxa-Michael reaction involving aliphatic alcohols as nucleophiles and ß-fluoroalkyl vinylsulfones catalyzed by bifunctional phosphonium salt (BPS), achieving high yields and excellent enantioselectivities (up to 98 % yield and 98 %â ee). Additionally, a sequential process including asymmetric oxa-Michael and debenzylation, facilitated by BPS/Lewis acid cooperation, was revealed for synthesizing diverse chiral secondary alcohol compounds in high yields (81-88 %) with consistent stereoselectivities. Furthermore, mechanistic explorations and subsequent results unveiled that the enantioselectivity originates from hydrogen-bonding and ion-pair interactions between the BPS catalyst and the substrates.
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Chemodivergent (de)hydrogenative coupling of primary and secondary alcohols is achieved utilizing an inexpensive nickel catalyst, (6-OH-bpy)NiCl2 . This protocol demonstrates the synthesis of branched carbonyl compounds, α,α-disubstituted ketones, and α-substituted chalcones via borrowing hydrogen strategy and acceptorless dehydrogenative coupling, respectively. A wide range of aryl-based secondary alcohols are coupled with various primary alcohols in this tandem dehydrogenation/hydrogenation reaction. The nickel catalyst, along with KOt Bu or K2 CO3 , governed the selectivity for the formation of branched saturated ketones or chalcones. A preliminary mechanistic investigation confirms the reversible dehydrogenation of alcohols to carbonyls via metal-ligand cooperation (MLC) and the involvement of radical intermediates during the reaction.
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A mechanochemistry approach is developed for regioselective synthesis of functionalized dihydropyrido[2,3-d]pyrimidines by milling propargylic alcohols and 6-aminouracils with HFIP/p-TsOH. In the case of tert-propargyl alcohols, this [3+3] cascade annulation proceeded through allenylation of uracil followed by a 6-endo trig cyclization. With sec-propargyl alcohols, the reaction furnished the propargylation of uracil. This atom economy ball milling reaction allows access to a broad range of dihydropyrido[2,3-d]pyrimidine derivatives in excellent yields. We demonstrated the gram scale synthesis of 3 g and post-synthetic modifications to effect the cyclization of 5 to 6.
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The direct conversion of methane into alcohol is a promising approach for achieving a low-carbon future, yet it remains a major challenge. In this study, we utilize density functional theory to explore the potential of the (CoCrFeMnNi)3O4 (CCFMNO) high entropy oxide (HEO) for electrochemical oxidation of methane to methanol and ethanol, alongside their competition with CO2 production. Our primary focus in this study is on thermodynamics, enabling a prompt analysis of the catalyst's potential, with the calculation of electrochemical barriers falling beyond our scope. Among all potential active sites within CCFMNO HEO, we identify Co as the most active site for methane activation when using carbonate ions as oxidants. This results in methanol production with a limiting potential of 1.4â VCHE, and ethanol and CO2 productions with a limiting potential of 1.2â VCHE. Additionally, our findings suggest that the occupied p-band center of O* on CCFMNO HEO is a potential descriptor for identifying the most active site within CCFMNO HEO. Overall, our results indicate that CCFMNO HEO holds promise as catalysts for methane oxidation to alcohols, employing carbonate ions as oxidants.