RESUMEN
We introduce STOPLIGHT, a web portal to assist medicinal chemists in prioritizing hits from screening campaigns and the selection of compounds for optimization. STOPLIGHT incorporates services to assess 6 physiochemical and structural properties, 6 assay liabilities, and 11 pharmacokinetic properties, for any small molecule represented by its SMILES string. We briefly describe each service and illustrate the utility of this portal with a case study. The STOPLIGHT portal provides a user-friendly tool to guide hit selection in early drug discovery campaigns, whereby compounds with unfavorable properties can be quickly recognized and eliminated.
Asunto(s)
Descubrimiento de Drogas , Descubrimiento de Drogas/métodos , Programas Informáticos , Evaluación Preclínica de Medicamentos/métodos , Internet , Bibliotecas de Moléculas Pequeñas/químicaRESUMEN
Tracing the globally circulating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) phylogenetic clades by high-throughput sequencing is costly, time-consuming, and labor-intensive. We here propose a rapid, simple, and cost-effective amplification refractory mutation system (ARMS)-based multiplex reverse-transcription polymerase chain reaction (PCR) assay to identify six distinct phylogenetic clades: S, L, V, G, GH, and GR. Our multiplex PCR is designed in a mutually exclusive way to identify V-S and G-GH-GR clade variants separately. The pentaplex assay included all five variants and the quadruplex comprised of the triplex variants alongside either V or S clade mutations that created two separate subsets. The procedure was optimized with 0.2-0.6 µM primer concentration, 56-60°C annealing temperature, and 3-5 ng/µl complementary DNA to validate on 24 COVID-19-positive samples. Targeted Sanger sequencing further confirmed the presence of the clade-featured mutations with another set of primers. This multiplex ARMS-PCR assay is a fast, low-cost alternative and convenient to discriminate the circulating phylogenetic clades of SARS-CoV-2.
Asunto(s)
Prueba de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , COVID-19/virología , Prueba de Ácido Nucleico para COVID-19/economía , Análisis Costo-Beneficio , Genotipo , Humanos , Reacción en Cadena de la Polimerasa Multiplex , Mutación , Filogenia , Reproducibilidad de los Resultados , SARS-CoV-2/clasificaciónRESUMEN
Degradation of soil and water from discharge of untreated industrial effluent is alarming in Bangladesh. Therefore, buildup of heavy metals in soil from contaminated effluent, their entry into the food chain and effects on rice yield were quantified in a pot experiment. The treatments were comprised of 0, 25%, 50%, 75% and 100% industrial effluents applied as irrigation water. Effluents, initial soil, different parts of rice plants and post-harvest pot soil were analyzed for various elements, including heavy metals. Application of elevated levels of effluent contributed to increased heavy metals in pot soils and rice roots due to translocation effects, which were transferred to rice straw and grain. The results indicated that heavy metal toxicity may develop in soil because of contaminated effluent application. Heavy metals are not biodegradable, rather they accumulate in soils, and transfer of these metals from effluent to soil and plant cells was found to reduce the growth and development of rice plants and thereby contributed to lower yield. Moreover, a higher concentration of effluent caused heavy metal toxicity as well as reduction of growth and yield of rice, and in the long run a more aggravated situation may threaten human lives, which emphasizes the obligatory adoption of effluent treatment before its release to the environment, and regular monitoring by government agencies needs to be ensured.
Asunto(s)
Metales Pesados/metabolismo , Oryza/crecimiento & desarrollo , Contaminantes del Suelo/metabolismo , Agricultura , Silicatos de Aluminio/análisis , Arcilla , Monitoreo del Ambiente , Oryza/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismoRESUMEN
Condensation of 2-hydroxy-benzophenone (HL') with (R or S)-(Ar)ethylamine yields the enantiopure Schiff bases (S or R)-2-((E)-1-(1-(Ar)ethylimino)ethyl)phenol {Ar = C6H5 (S- or R-HL1), p-CH3OC6H4 (S- or R-HL2)}. These Schiff bases react with copper(ii) acetate under reflux to give green microcrystals of bis[(R or S)-2-((E)-1-(1-(Ar)ethylimino)ethyl)phenolato-κ2N,O]-Λ/Δ-copper(ii), {Ar = C6H5 (Λ/Δ-Cu-R- or S-L1), p-CH3OC6H4 (Λ/Δ-Cu-R- or S-L2)} with induction of Λ/Δ-chirality at-metal. The presence of Schiff base ligands in the paramagnetic green microcrystals is confirmed by decomplexation reaction with NaCN via reduction of Cu(ii) to Cu(i) in DMSO-d6 solution. Crystallization attempts of the green microcrystalline Schiff-base Cu complexes provide deep-green block-shaped crystals of an about equal admixture of bis[2-oxo-benzophenonato-κ2O,O']-copper(ii), (CuL'2) and bis[2-(imino(phenyl)methyl)phenolato-κ2N,O]copper(ii), (CuL''2) via in situ hydrolysis of the coordinated Schiff base ligands back to 2-hydroxy-benzophenone (HL') and to 2-(imino(phenyl)methyl)phenol (HL''), which in-turn bind with the copper(ii) ion. Powder X-ray diffraction (PXRD) patterns of R-HL1 and Cu-R-L1 allowed their structure determinations using the program Expo-2014 followed by Rietveld refinement. The Cu structures refined to four-coordinated Λ/Δ-copper(ii)-complexes by the two phenolate-oxygen and two imine-nitrogen atoms from two Schiff base ligands in a pseudotetrahedral geometry. DFT optimized structures (at gas-phase) reveal the Δ-Cu-S-L1 or Λ-Cu-R-L1 diastereomer as slightly more stable than the corresponding Λ-Cu-S-L1 or Δ-Cu-R-L1 by ca. 7.60 kcal mol-1, resulting from diastereoselectively induced Λ vs. Δ-chirality at-metal. Electronic circular dichroism (ECD) spectra display mirror-image relationships and comparisons of experimental and simulated ECD spectra by TDDFT suggest an excess of the Δ-Cu-S-L1 or Λ-Cu-R-L1 diastereomer in solution. The cyclic voltammograms demonstrate two one electron charge transfer processes for Cu2+/Cu+ and Cu+/Cu0 couples in acetonitrile, respectively.