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1.
Proc Natl Acad Sci U S A ; 119(11): e2118220119, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35254915

RESUMO

SignificanceChemical genetics, which investigates biological processes using small molecules, is gaining interest in plant research. However, a major challenge is to uncover the mode of action of the small molecules. Here, we applied the cellular thermal shift assay coupled with mass spectrometry (CETSA MS) to intact Arabidopsis cells and showed that bikinin, the plant-specific glycogen synthase kinase 3 (GSK3) inhibitor, changed the thermal stability of some of its direct targets and putative GSK3-interacting proteins. In combination with phosphoproteomics, we also revealed that GSK3s phosphorylated the auxin carrier PIN-FORMED1 and regulated its polarity that is required for the vascular patterning in the leaf.


Assuntos
Brassinosteroides/metabolismo , Ácidos Indolacéticos/metabolismo , Proteoma , Transdução de Sinais , Aminopiridinas/metabolismo , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Fosfoproteínas/metabolismo , Ligação Proteica , Estabilidade Proteica , Proteômica/métodos , Succinatos/metabolismo
2.
Opt Express ; 32(3): 3480-3491, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297568

RESUMO

Structured illumination is essential for high-performance ptychography. Especially in the extreme ultraviolet (EUV) range, where reflective optics are prevalent, the generation of structured beams is challenging and, so far, mostly amplitude-only masks have been used. In this study, we generate a highly structured beam using a phase-shifting diffuser optimized for 13.5 nm wavelength and apply this beam to EUV ptychography. This tailored illumination significantly enhances the quality and resolution of the ptychography reconstructions. In particular, when utilizing the full dynamics range of the detector, the resolution has been improved from 125 nm, when using an unstructured beam, to 34 nm. Further, ptychography enables the quantitative measurement of both the amplitude and phase of the EUV diffuser at 13.5 nm wavelength. This capability allows us to evaluate the influence of imperfections and contaminations on its "at wavelength" performance, paving the way for advanced EUV metrology applications and highlighting its importance for future developments in nanolithography and related fields.

3.
Medicina (Kaunas) ; 60(4)2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38674224

RESUMO

Background and Objectives: Although there is strong evidence of the positive effects of physical exercise on health, adherence to face-to-face exercise programs in the adult population is low, identifying several barriers that hinder their practice. There is research that demonstrates the viability of physical exercise programs with the use of Mobile Health in Ecological Momentary Assessment (EMA) mode, which contributes to overcoming many reported barriers. To synthesize the methodological characteristics and health effects of physical exercise programs based on mobile health in EMA modality in adults in developing countries. Materials and Methods: This systematic review was conducted according to guidelines established by the PRISMA statement in APA PsycArticles and CINAHL databases by EBSCOhost, Cochrane Library, PubMed, and Web of Science for articles published between 2008 and March 2024. Results: Telephone counseling on clinical-behavioral factors is believed to reduce morbidity and mortality in developed countries, but this aspect is not explored in developing countries. We included nine randomized controlled trials with a total of 4394 male and female participants aged 18 to 60 years. The interventions were mainly carried out by text messages, lasting between 20 to 80 min per session, 3 to 5 days per week, and most were carried out over 12 months. The interventions on the variables of physical activity, nutrition, and medical assessments showed significant effects, and variables such as quality of life and anthropometric measurements were not significant in most studies. Conclusions: This systematic review included studies from different developing countries, the most common diseases being diabetes, overweight, obesity, and hypertension. All the studies used mobile devices as the technology, finding a profile of the adults studied, as well as the characteristics of exercise programs based on mobile health in EMA modality.


Assuntos
Países em Desenvolvimento , Avaliação Momentânea Ecológica , Exercício Físico , Saúde Mental , Telemedicina , Humanos , Exercício Físico/psicologia , Exercício Físico/fisiologia , Telemedicina/métodos , Adulto , Meio Social , Cognição/fisiologia , Masculino , Feminino , Pessoa de Meia-Idade
4.
Opt Express ; 31(16): 26958-26968, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710544

RESUMO

We examine the interplay between spectral bandwidth and illumination curvature in ptychography. By tailoring the divergence of the illumination, broader spectral bandwidths can be tolerated without requiring algorithmic modifications to the forward model. In particular, a strong wavefront curvature transitions a far-field diffraction geometry to an effectively near-field one, which is less affected by temporal coherence effects. The relaxed temporal coherence requirements allow for leveraging wider spectral bandwidths and larger illumination spots. Our findings open up new avenues towards utilizing pink and broadband beams for increased flux and throughput at both synchrotron facilities and lab-scale beamlines.

5.
Opt Express ; 31(9): 14212-14224, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37157290

RESUMO

We present high-speed and wide-field EUV ptychography at 13.5 nm wavelength using a table-top high-order harmonic source. Compared to previous measurements, the total measurement time is significantly reduced by up to a factor of five by employing a scientific complementary metal oxide semiconductor (sCMOS) detector that is combined with an optimized multilayer mirror configuration. The fast frame rate of the sCMOS detector enables wide-field imaging with a field of view of 100 µm × 100 µm with an imaging speed of 4.6 Mpix/h. Furthermore, fast EUV wavefront characterization is employed using a combination of the sCMOS detector with orthogonal probe relaxation.

6.
Opt Express ; 31(9): 13763-13797, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37157257

RESUMO

Conventional (CP) and Fourier (FP) ptychography have emerged as versatile quantitative phase imaging techniques. While the main application cases for each technique are different, namely lens-less short wavelength imaging for CP and lens-based visible light imaging for FP, both methods share a common algorithmic ground. CP and FP have in part independently evolved to include experimentally robust forward models and inversion techniques. This separation has resulted in a plethora of algorithmic extensions, some of which have not crossed the boundary from one modality to the other. Here, we present an open source, cross-platform software, called PtyLab, enabling both CP and FP data analysis in a unified framework. With this framework, we aim to facilitate and accelerate cross-pollination between the two techniques. Moreover, the availability in Matlab, Python, and Julia will set a low barrier to enter each field.

7.
Rev Med Chil ; 151(7): 869-879, 2023 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-39093176

RESUMO

Metabolic syndrome (MetS) is prevalent in our population. The purpose of this study is to evaluate the effect of physical exercise, assisted by a mobile application (m-Health), on cardiorespiratory fitness (ACR) and cardiovascular risk markers in women with metabolic disorders typical of MetS, and to compare it with the effect of exercise monitored face to face in women with similar characteristics. MATERIALS AND METHODS: Controlled experimental study with two arms. Forty-one women with metabolic disorders were recruited; 14 completed the study and, for convenience, formed the intervention group with m-Health or the control group with the Vida Sana Program, both carried out for ten weeks. ACR, body composition, anthropometry, and blood pressure (BP) were evaluated before and after the intervention. RESULTS: 95% of the women presented low and very low basal ACR. The group treated with m-Health after 10 weeks increased VO2max (% change: + 44.4; p = 0.035) and decreased waist circumference (% change: -2.6; p = 0.022) and DBP (% change: -14.1; p = 0.036). Meanwhile, the control group decreased waist circumference (% change: -6.5; p = 0.015) and DBP (% change: -12.2; p = 0.05) but did not change VO2 max. Comparisons between groups did not show differences. CONCLUSIONS: A physical exercise program via m-Health improved ACR and anthropometric parameters in women with cardiometabolic disorders.


Assuntos
Aptidão Cardiorrespiratória , Terapia por Exercício , Síndrome Metabólica , Aplicativos Móveis , Humanos , Feminino , Aptidão Cardiorrespiratória/fisiologia , Síndrome Metabólica/fisiopatologia , Síndrome Metabólica/terapia , Pessoa de Meia-Idade , Adulto , Terapia por Exercício/métodos , Circunferência da Cintura/fisiologia , Consumo de Oxigênio/fisiologia , Pressão Sanguínea/fisiologia , Exercício Físico/fisiologia
8.
Lancet ; 398(10315): 1965-1973, 2021 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-34793746

RESUMO

BACKGROUND: Intragastric balloons are anatomy-preserving, minimally invasive obesity therapies. Enhanced tolerance and durability could help broaden clinical adoption. We investigated the safety and efficacy of an adjustable intragastric balloon (aIGB) in adults with obesity. METHODS: In this prospective, multicentre, open-label, randomised clinical trial done at seven US sites, adults aged 22-65 years with obesity were randomly assigned (2:1) to aIGB with lifestyle intervention or lifestyle intervention alone (control) for 32 weeks. Balloon volume could be increased to facilitate weight loss or decreased for tolerability. Coprimary endpoints included mean percentage total bodyweight loss and responder rate (≥5% total bodyweight loss) at 32 weeks. We used a multiple imputed intention-to-treat population analysis. This study was registered with ClinicalTrials.gov, NCT02812160. FINDINGS: Between Aug 9, 2016, and Dec 7, 2018, we randomly assigned 288 patients to aIGB (n=187 [65%]) or control (n=101 [35%]) groups. Mean total bodyweight loss at 32 weeks was 15·0% (95% CI 13·9-16·1) in the aIGB group versus 3·3% (2·0-4·6) in the control group (p<0·0001). Clinical response was observed in 171 (92%) patients in the aIGB group. Adjustments to the aIGB occurred in 145 (80%) patients for weight loss plateau or intolerance. Upward volume adjustment facilitated an additional mean 5·2% (4·5-5·8) total bodyweight loss. Downward volume adjustment allowed 21 (75%) patients in the aIGB group to complete the full duration of therapy. Intolerance caused early removal of the device in 31 (17%) patients. No micronutrient deficiencies were observed in the aIGB cohort. Device-related serious adverse events were observed in seven (4%) patients, without any deaths. INTERPRETATION: When aIGB was combined with lifestyle modification, significant weight loss was achieved and maintained for 6 months following removal. Balloon volume adjustability permitted individualised therapy, maximising weight loss and tolerance. FUNDING: Spatz Medical.


Assuntos
Balão Gástrico , Obesidade/terapia , Redução de Peso , Adulto , Remoção de Dispositivo , Feminino , Gastroscopia , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
9.
Int J Mol Sci ; 23(23)2022 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-36499165

RESUMO

The PCTAIRE subfamily belongs to the CDK (cyclin-dependent kinase) family and represents an understudied class of kinases of the dark kinome. They exhibit a highly conserved binding pocket and are activated by cyclin Y binding. CDK16 is targeted to the plasma membrane after binding to N-myristoylated cyclin Y and is highly expressed in post-mitotic tissues, such as the brain and testis. Dysregulation is associated with several diseases, including breast, prostate, and cervical cancer. Here, we used the N-(1H-pyrazol-3-yl)pyrimidin-4-amine moiety from the promiscuous inhibitor 1 to target CDK16, by varying different residues. Further optimization steps led to 43d, which exhibited high cellular potency for CDK16 (EC50 = 33 nM) and the other members of the PCTAIRE and PFTAIRE family with 20-120 nM and 50-180 nM, respectively. A DSF screen against a representative panel of approximately 100 kinases exhibited a selective inhibition over the other kinases. In a viability assessment, 43d decreased the cell count in a dose-dependent manner. A FUCCI cell cycle assay revealed a G2/M phase cell cycle arrest at all tested concentrations for 43d, caused by inhibition of CDK16.


Assuntos
Quinases Ciclina-Dependentes , Ciclinas , Masculino , Humanos , Ciclinas/metabolismo , Sequência de Aminoácidos , Quinases Ciclina-Dependentes/metabolismo , Ligação Proteica
10.
Angew Chem Int Ed Engl ; 61(23): e202203175, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35325497

RESUMO

By limiting the nitrogen source to glutamic acid, we isolated cyclic peptides from Euglena gracilis containing asparagine and non-proteinogenic amino acids. Structure elucidation was accomplished through spectroscopic methods, mass spectrometry and chemical degradation. The euglenatides potently inhibit pathogenic fungi and cancer cell lines e.g., euglenatide B exhibiting IC50 values of 4.3 µM in Aspergillus fumigatus and 0.29 µM in MCF-7 breast cancer cells. In an unprecedented convergence of non-ribosomal peptide synthetase and polyketide synthase assembly-line biosynthesis between unicellular species and the metazoan kingdom, euglenatides bear resemblance to nemamides from Caenorhabditis elegans and inhibited both producing organisms E. gracilis and C. elegans. By molecular network analysis, we detected over forty euglenatide-like metabolites in E. gracilis, E. sanguinea and E. mutabilis, suggesting an important biological role for these natural products.


Assuntos
Euglena gracilis , Microalgas , Animais , Caenorhabditis elegans , Euglena gracilis/metabolismo , Água Doce , Peptídeos Cíclicos/metabolismo , Peptídeos Cíclicos/farmacologia
11.
J Nat Prod ; 84(4): 1127-1134, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33793225

RESUMO

Pentaminomycins F-H (1-3), a group of three new hydroxyarginine-containing cyclic pentapeptides, were isolated from cultures of a Streptomyces cacaoi subsp. cacaoi strain along with the known pentaminomycins A-E. The structures of the new peptides were determined by a combination of mass spectrometry, NMR, and Marfey's analyses. Pentaminomycins F (1) and G (2) were shown to contain the rare amino acid 3-(2-pyridyl)-alanine. This finding represents the first reported examples of nonribosomal peptides containing this residue. The ldlld chiral sequence found for the three compounds was in agreement with that reported for previously isolated pentaminomycins and consistent with the epimerization domains present in the putative nonribosomal peptide synthetase (NRPS) biosynthetic gene cluster.


Assuntos
Alanina/química , Peptídeos Cíclicos/química , Piridinas/química , Streptomyces/química , Estrutura Molecular
12.
Molecules ; 26(21)2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34770989

RESUMO

Streptomyces are well-known producers of a range of different secondary metabolites, including antibiotics and other bioactive compounds. Recently, it has been demonstrated that "silent" biosynthetic gene clusters (BGCs) can be activated by heterologously expressing transcriptional regulators from other BGCs. Here, we have activated a silent BGC in Streptomyces sp. CA-256286 by overexpression of a set of SARP family transcriptional regulators. The structure of the produced compound was elucidated by NMR and found to be an N-acetyl cysteine adduct of the pyranonaphtoquinone polyketide 3'-O-α-d-forosaminyl-(+)-griseusin A. Employing a combination of multi-omics and metabolic engineering techniques, we identified the responsible BGC. These methods include genome mining, proteomics and transcriptomics analyses, in combination with CRISPR induced gene inactivations and expression of the BGC in a heterologous host strain. This work demonstrates an easy-to-implement workflow of how silent BGCs can be activated, followed by the identification and characterization of the produced compound, the responsible BGC, and hints of its biosynthetic pathway.


Assuntos
Biologia Computacional , Streptomyces/química , Fatores de Transcrição/metabolismo , Estrutura Molecular , Naftoquinonas/análise , Naftoquinonas/metabolismo , Streptomyces/metabolismo , Fatores de Transcrição/genética , Transcrição Gênica/genética
13.
Appl Intell (Dordr) ; 51(9): 6497-6527, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34764606

RESUMO

The17 Sustainable Development Goals (SDGs) established by the United Nations Agenda 2030 constitute a global blueprint agenda and instrument for peace and prosperity worldwide. Artificial intelligence and other digital technologies that have emerged in the last years, are being currently applied in virtually every area of society, economy and the environment. Hence, it is unsurprising that their current role in the pursuance or hampering of the SDGs has become critical. This study aims at providing a snapshot and comprehensive view of the progress made and prospects in the relationship between artificial intelligence technologies and the SDGs. A comprehensive review of existing literature has been firstly conducted, after which a series SWOT (Strengths, Weaknesses, Opportunities and Threats) analyses have been undertaken to identify the strengths, weaknesses, opportunities and threats inherent to artificial intelligence-driven technologies as facilitators or barriers to each of the SDGs. Based on the results of these analyses, a subsequent broader analysis is provided, from a position vantage, to (i) identify the efforts made in applying AI technologies in SDGs, (ii) pinpoint opportunities for further progress along the current decade, and (iii) distill ongoing challenges and target areas for important advances. The analysis is organized into six categories or perspectives of human needs: life, economic and technological development, social development, equality, resources and natural environment. Finally, a closing discussion is provided about the prospects, key guidelines and lessons learnt that should be adopted for guaranteeing a positive shift of artificial intelligence developments and applications towards fully supporting the SDGs attainment by 2030.

14.
Emerg Infect Dis ; 26(1): 150-153, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674901

RESUMO

Most human hantavirus infections occur in Asia, but some cases have been described in Europe in travelers returning from Asia. We describe a case of hantavirus pulmonary syndrome in a previously healthy traveler occurring shortly after he returned to Spain from Nepal. Serologic tests suggested a Puumala virus-like infection.


Assuntos
Síndrome Pulmonar por Hantavirus/epidemiologia , Viagem , Adulto , Síndrome Pulmonar por Hantavirus/diagnóstico , Síndrome Pulmonar por Hantavirus/etiologia , Síndrome Pulmonar por Hantavirus/virologia , Humanos , Masculino , Nepal/epidemiologia , Virus Puumala , Espanha/epidemiologia
15.
Angew Chem Int Ed Engl ; 59(31): 12654-12658, 2020 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-32407589

RESUMO

Lantibiotics are ribosomally synthesized and post-translationally modified peptides (RiPPs) characterized by the presence of lanthionine or methyllanthionine rings and their antimicrobial activity. Cacaoidin, a novel glycosylated lantibiotic, was isolated from a Streptomyces cacaoi strain and fully characterized by NMR, mass spectrometry, chemical derivatization approaches and genome analysis. The new molecule combines outstanding structural features, such as a high number of d-amino acids, an uncommon glycosylated tyrosine residue and an unprecedented N,N-dimethyl lanthionine. This latter feature places cacaoidin within a new RiPP family located between lanthipeptides and linaridins, here termed lanthidins. Cacaoidin displayed potent antibacterial activity against Gram-positive pathogens including Clostridium difficile. The biosynthetic gene cluster showed low homology with those of other known lanthipeptides or linaridins, suggesting a new RiPP biosynthetic pathway.


Assuntos
Antibacterianos/farmacologia , Bacteriocinas/farmacologia , Glicopeptídeos/farmacologia , Sequência de Aminoácidos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Bacteriocinas/química , Bacteriocinas/isolamento & purificação , Clostridioides difficile/efeitos dos fármacos , Glicopeptídeos/química , Glicopeptídeos/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Streptomyces/química
16.
Annu Rev Pharmacol Toxicol ; 56: 141-61, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26566155

RESUMO

A drug must engage its intended target to achieve its therapeutic effect. However, conclusively measuring target engagement (TE) in situ is challenging. This complicates preclinical development and is considered a key factor in the high rate of attrition in clinical trials. Here, we discuss a recently developed, label-free, biophysical assay, the cellular thermal shift assay (CETSA), which facilitates the direct assessment of TE in cells and tissues at various stages of drug development. CETSA also reveals biochemical events downstream of drug binding and therefore provides a promising means of establishing mechanistic biomarkers. The implementation of proteome-wide CETSA using quantitative mass spectrometry represents a novel strategy for defining off-target toxicity and polypharmacology and for identifying downstream mechanistic biomarkers. The first year of CETSA applications in the literature has focused on TE studies in cell culture systems and has confirmed the broad applicability of CETSA to many different target families. The next phase of CETSA applications will likely encompass comprehensive animal and patient studies, and CETSA will likely serve as a very valuable tool in many stages of preclinical and clinical drug development.


Assuntos
Bioensaio/métodos , Biomarcadores/metabolismo , Animais , Sistemas de Liberação de Medicamentos/métodos , Descoberta de Drogas/métodos , Humanos , Proteoma/metabolismo
17.
Chemistry ; 25(53): 12367-12379, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31278780

RESUMO

The combination of the surface-adhesive properties of catechol rings and functional moieties conveying specific properties is very appealing to materials chemistry, but the preparation of catechol derivatives often requires elaborate synthetic routes to circumvent the intrinsic reactivity of the catechol ring. In this work, functional catechols are synthesized straightforwardly by using the bioinspired reaction of several functional thiols with o-benzoquinone. With one exception, the conjugated addition of the thiol takes place regioselectively at the 3-position of the quinone, and is rationalized by DFT calculations. Overall, this synthetic methodology provides a general and straightforward access to functional and chain-extended catechol derivatives, which are later tested with regard to their hydro-/oleophobicity, colloidal stability, fluorescence, and metal-coordinating capabilities in proof-of-concept applications.


Assuntos
Catecóis , Catecóis/química , Metais/química , Compostos de Sulfidrila/química , Propriedades de Superfície
18.
J Electrochem Soc ; 166(2): B125-B132, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31341328

RESUMO

A microfluidic platform for hydrodynamic electrochemical analysis was developed, consisting of a poly(methyl methacrylate) chip and three removable electrodes, each housed in 1/16" OD polyether ether ketone tube which can be removed independently for polishing or replacement. The working electrode was a 100-µm diameter Pt microdisk, located flush with the upper face of a 150 µm × 20 µm × 3 cm microchannel, smaller than previously reported for these types of removable electrodes. A commercial leak-less reference electrode was utilized, and a coiled platinum wire was the counter electrode. The platform was evaluated electrochemically by oxidizing a potassium ferrocyanide solution at the working electrode, and a typical limiting current behavior was observed after running linear sweep voltammetry and chronoamperometry, with flow rates 1-6 µL/min. While microdisk channel electrodes have been simulated before using a finite difference method in an ideal 3D geometry, here we predict the limiting current using finite elements in COMSOL Multiphysics 5.3a, which allowed us to easily explore variations in the microchannel geometry that have not previously been considered in the literature. Experimental and simulated currents showed the same trend but differed by 41% in simulations of the ideal geometry, which improved when channel and electrode imperfections were included.

19.
Mar Drugs ; 18(1)2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31888028

RESUMO

As part of our continuing efforts to discover new bioactive compounds from microbial sources, a reinvestigation of extracts of scaled-up cultures of the marine-derived Streptomyces sp. strain CA-271078 resulted in the isolation and structural elucidation of four new napyradiomycins (1-3, 5). The known napyradiomycin SC (4), whose structural details had not been previously described in detail, and another ten related known compounds (6-15). The structures of the new napyradiomycins were characterized by HRMS and 1D- and 2D-NMR spectroscopies and their relative configurations were established through a combination of molecular modelling with nOe and coupling constants NMR analysis. The absolute configuration of each compound is also proposed based on biosynthetic arguments and the comparison of specific rotation data with those of related compounds. Among the new compounds, 1 was determined to be the first non-halogenated member of napyradiomycin A series containing a functionalized prenyl side chain, while 2-4 harbor in their structures the characteristic chloro-cyclohexane ring of the napyradiomycin B series. Remarkably, compound 5 displays an unprecedented 14-membered cyclic ether ring between the prenyl side chain and the chromophore, thus representing the first member of a new class of napyradiomycins that we have designated as napyradiomycin D1. Anti-infective and cytotoxic properties for all isolated compounds were evaluated against a set of pathogenic microorganisms and the HepG2 cell line, respectively. Among the new compounds, napyradiomycin D1 exhibited significant growth-inhibitory activity against methicillin-resistant Staphylococcus aureus, Mycobacterium tuberculosis, and HepG2.


Assuntos
Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Naftoquinonas/farmacologia , Streptomyces/química , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Naftoquinonas/química , Naftoquinonas/isolamento & purificação
20.
Nat Chem Biol ; 12(10): 815-21, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27526030

RESUMO

The structure-specific nuclease human flap endonuclease-1 (hFEN1) plays a key role in DNA replication and repair and may be of interest as an oncology target. We present the crystal structure of inhibitor-bound hFEN1, which shows a cyclic N-hydroxyurea bound in the active site coordinated to two magnesium ions. Three such compounds had similar IC50 values but differed subtly in mode of action. One had comparable affinity for protein and protein-substrate complex and prevented reaction by binding to active site catalytic metal ions, blocking the necessary unpairing of substrate DNA. Other compounds were more competitive with substrate. Cellular thermal shift data showed that both inhibitor types engaged with hFEN1 in cells, and activation of the DNA damage response was evident upon treatment with inhibitors. However, cellular EC50 values were significantly higher than in vitro inhibition constants, and the implications of this for exploitation of hFEN1 as a drug target are discussed.


Assuntos
Inibidores Enzimáticos/farmacologia , Endonucleases Flap/antagonistas & inibidores , Endonucleases Flap/metabolismo , Domínio Catalítico/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Endonucleases Flap/química , Humanos , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade , Temperatura
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