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1.
Eur J Nucl Med Mol Imaging ; 51(6): 1703-1712, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38191817

RESUMO

PURPOSE: Boramino acids are a class of amino acid biomimics that replace the carboxylate group with trifluoroborate and can achieve the 18F-labeled positron emission tomography (PET) and boron neutron capture therapy (BNCT) with identical chemical structure. METHODS: This study reports a trifluoroborate-derived boronophenylalanine (BBPA), a derived boronophenylalanine (BPA) for BNCT, as a promising PET tracer for tumor imaging. RESULTS: Competition inhibition assays in cancer cells suggested the cell accumulation of [18F]BBPA is through large neutral amino acid transporter type-1 (LAT-1). Of note, [18F]BBPA is a pan-cancer probe that shows notable tumor uptake in B16-F10 tumor-bearing mice. In the patients with gliomas and metastatic brain tumors, [18F]BBPA-PET shows good tumor uptake and notable tumor-to-normal brain ratio (T/N ratio, 18.7 ± 5.5, n = 11), higher than common amino acid PET tracers. The [18F]BBPA-PET quantitative parameters exhibited no difference in diverse contrast-enhanced status (P = 0.115-0.687) suggesting the [18F]BBPA uptake was independent from MRI contrast-enhancement. CONCLUSION: This study outlines a clinical trial with [18F]BBPA to achieve higher tumor-specific accumulation for PET, provides a potential technique for brain tumor diagnosis, and might facilitate the BNCT of brain tumors.


Assuntos
Compostos de Boro , Neoplasias Encefálicas , Radioisótopos de Flúor , Fenilalanina , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Traçadores Radioativos , Animais , Feminino , Humanos , Camundongos , Compostos de Boro/análise , Compostos de Boro/metabolismo , Compostos de Boro/farmacocinética , Terapia por Captura de Nêutron de Boro , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/metabolismo , Radioisótopos de Flúor/análise , Radioisótopos de Flúor/metabolismo , Radioisótopos de Flúor/farmacocinética , Voluntários Saudáveis , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Imageamento por Ressonância Magnética , Melanoma Experimental , Camundongos Endogâmicos C57BL , Sondas Moleculares/análise , Sondas Moleculares/metabolismo , Sondas Moleculares/farmacocinética , Fenilalanina/análogos & derivados , Fenilalanina/análise , Fenilalanina/metabolismo , Fenilalanina/farmacocinética , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Soft Matter ; 20(33): 6635-6647, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39109438

RESUMO

Rapid adsorption of surfactants onto a freshly formed interface is vital for emulsification because emulsification is a competitive process occurring between the very short time span of interface formation and surfactant mass transport. The biosurfactant surfactin has been previously reported to reach adsorption equilibrium at the hydrophobic/hydrophilic interface within hundreds of milliseconds and rapidly reduce the interfacial tension compared to chemically synthesized surfactants. According to a prior study, surfactin is expected to exhibit good performance in stabilizing micro-droplets of oil within the aging time scale of milliseconds. Herein, the stabilities of micro-droplets of n-hexadecane in the presence of a biosurfactant, surfactin (C15-SFT), and a chemically synthesized surfactant, sodium cetyl benzene sulfonate (8-SCBS), were investigated using a microfluidic method. The coalescence frequency of micro-droplets, the evolution of micro-droplet size, and the coalescence time of micro-droplets were evaluated. The results indicated that C15-SFT exhibited superiority over 8-SCBS in stabilizing the micro-droplets of n-hexadecane. Biosurfactant C15-SFT effectively reduced the fusion probability between oil droplets and elongated the coalescence time compared to 8-SCBS, and these phenomena were obvious at a shorter aging time (150 ms) and lower surfactant concentration (0.1 × critical micelle concentration). The stabilities of micro-droplets increased with aging time and the bulk concentration of surfactants. Stable micro-droplets of n-hexadecane were formed in 1 × 10-4 mol L-1 C15-SFT solution at 600 ms aging time, and the bulk concentration was 1 × 10-3 mol L-1 in the case of 8-SCBS. The micro-droplets rarely coalesced in the presence of 1 × 10-4 mol L-1 C15-SFT after 600 ms aging time, but the micro-droplets in 1 × 10-4 mol L-1 8-SCBS coalesced frequently in the midstream and downstream of the coalescence chamber, and big droplets were dominant in the emulsion. The coalescence time of micro-droplets stabilized by C15-SFT was obviously longer than that of those stabilized by 8-SCBS under the same condition, indicating that the interfacial film formed by C15-SFT has much strength to resist coalescence during collisions. This work is helpful for understanding the activity of lipopeptides in the very short early stage of the emulsification process, laying the foundation for biosurfactant research in the fields of enhanced oil recovery, bioremediation of contaminated water or soil, etc.

3.
Chemotherapy ; : 1-14, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39128459

RESUMO

INTRODUCTION: Osimertinib (AZD9291) is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor that has shown significant clinical benefits in patients with EGFR-sensitizing mutations or the EGFR T790M mutation. The homologous recombination (HR) pathway is crucial for repairing DNA double-strand breaks (DSBs). Rad51 plays a central role in HR, facilitating the search for homology and promoting DNA strand exchange between homologous DNA molecules. Rad51 is overexpressed in numerous types of cancer cells. B02, a specific small molecule inhibitor of Rad51, inhibits the DNA strand exchange activity of Rad51. Previous studies have indicated that B02 disrupted Rad51 foci formation in response to DNA damage and inhibited DSBs repair in human cells and sensitized them to chemotherapeutic drugs in vitro and in vivo. However, the potential therapeutic effects of combining osimertinib with a Rad51 inhibitor are not well understood. The aim of this study was to elucidate whether the downregulation of Rad51 expression and activity can enhance the osimertinib-induced cytotoxicity in non-small cell lung cancer (NSCLC) cells. METHODS: We used the MTS, trypan blue dye exclusion and colony-formation ability assay to determine whether osimertinib alone or in combination with B02 had cytotoxic effects on NSCLC cell lines. Real-time polymerase chain reaction was conducted to measure the amounts of Rad51 mRNA. The protein levels of phosphorylated AKT and Rad51 were determined by Western blot analysis. RESULTS: We found that osimertinib reduced Rad51 expression by inactivating AKT activity. Rad51 knockdown using small interfering RNA or AKT inactivation through the phosphatidylinositol 3-kinase inhibitor LY294002 or si-AKT RNA transfection enhanced the cytotoxic and growth inhibitory effects of osimertinib. In contrast, AKT-CA (a constitutively active form of AKT) vector-enforced expression could mitigate the cytotoxic and cell growth inhibitory effects of osimertinib. Furthermore, B02 significantly enhanced the cytotoxic and cell growth inhibitory effects of osimertinib in NSCLC cells. Compared to parental cells, the activation of AKT and Rad51 expression in osimertinib-resistant cells could not be significantly inhibited by osimertinib treatment. Moreover, the increased expression of Rad51 is associated with the resistance mechanism in osimertinib-resistant H1975 and A549 cells. CONCLUSION: Collectively, the downregulation of Rad51 expression and activity enhances the cytotoxic effect of osimertinib in human NSCLC cells.

4.
Molecules ; 29(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38474557

RESUMO

This study involved the design and synthesis of a series of novel 4-chromanone-derived compounds. Their in vivo anti-cucumber mosaic virus (CMV) activity in field trials against CMV disease in Passiflora spp. was then assessed. Bioassay results demonstrated that compounds 7c and 7g exhibited remarkable curative effects and protection against CMV, with inhibition rates of 57.69% and 51.73% and 56.13% and 52.39%, respectively, surpassing those of dufulin and comparable to ningnanmycin. Field trials results indicated that compound 7c displayed significant efficacy against CMV disease in Passiflora spp. (passion fruit) after the third spraying at a concentration of 200 mg/L, with a relative control efficiency of 47.49%, surpassing that of dufulin and comparable to ningnanmycin. Meanwhile, nutritional quality test results revealed that compound 7c effectively enhanced the disease resistance of Passiflora spp., as evidenced by significant increases in soluble protein, soluble sugar, total phenol, and chlorophyll contents in Passiflora spp. leaves as well as improved the flavor and taste of Passiflora spp. fruits, as demonstrated by notable increases in soluble protein, soluble sugar, soluble solid, and vitamin C contents in Passiflora spp. fruits. Additionally, a transcriptome analysis revealed that compound 7c primarily targeted the abscisic acid (ABA) signaling pathway, a crucial plant hormone signal transduction pathway, thereby augmenting resistance against CMV disease in Passiflora spp. Therefore, this study demonstrates the potential application of these novel 4-chromanone-derived compounds as effective inducers of plant immunity for controlling CMV disease in Passiflora spp. in the coming decades.


Assuntos
Cromonas , Cucumovirus , Infecções por Citomegalovirus , Passiflora , Frutas , Resistência à Doença , Açúcares/metabolismo
5.
Angew Chem Int Ed Engl ; 63(44): e202407443, 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39058370

RESUMO

The C-C coupling of methane (CH4) and carbon dioxide (CO2) to generate acetic acid (CH3COOH) represents a highly atom-efficient chemical conversion, fostering the comprehensive utilization of greenhouse gases. However, the inherent thermodynamic stability and kinetic inertness of CH4 and CO2 present obstacles to achieving efficient and selective conversion at room temperature. Our study reveals that hydroxyl radicals (⋅OH) and hydrated electrons (eaq -) produced by water radiolysis can effectively activate CH4 and CO2, yielding methyl radicals (⋅CH3) and carbon dioxide radical anions(⋅CO2 -) that facilitate the production of CH3COOH at ambient temperature. The introduction of radiation-synthesized CuO-anchored TiO2 bifunctional catalyst could further enhance reaction efficiency and selectivity remarkably by boosting radiation absorption and radical stability, resulting in a concentration of 7.1 mmol ⋅ L-1 of CH3COOH with near-unity selectivity (>95 %). These findings offer valuable insights for catalyst design and implementation in radiation-induced chemical conversion.

6.
Angew Chem Int Ed Engl ; : e202413249, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39349362

RESUMO

Trifluoroborate boronophenylalanine (BBPA) is a boron amino acid analog of 4­boronophenylalanine (BPA) but with a trifluoroborate group (-BF3-) instead of a carboxyl group (-COOH). Clinical studies have shown that 18F-labeled BBPA ([18F]BBPA) can produce high-contrast tumor images in positron emission tomography (PET). Beyond PET imaging, BBPA is a theranostic agent for boron neutron capture therapy (BNCT). Because BBPA possesses an identical chemical structure to BNCT and PET, it can potentially predict the boron concentration for BNCT using [18F]BBPA-PET. The synthesis of BBPA was achieved by selectively fluorinating the α-aminoborate compound, taking advantage of the varying rates of solvolysis of the B-F bond. The study showcased the high-contrast [18F]BBPA-PET imaging in various tumor models, highlighting its broad applicability for both [18F]BBPA-PET and BBPA-BNCT. [18F]BBPA-PET tumor uptake remains consistent across various doses, including those used in BNCT. This enables accurate estimation of the boron concentration in tumors using [18F]BBPA-PET. With its dual boron structure, BBPA increases boron concentration in tumor cells and tumor tissues compared to BPA. Thus, less boron carrier is needed. This study introduces a new theranostic boron carrier that enhances boron accumulation in tumors, predicts boron concentration, and enhances the accuracy and effectiveness of BNCT.

7.
Biotechnol Appl Biochem ; 70(6): 1806-1816, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37278163

RESUMO

Rhamnolipid, as a low-toxic, biodegradable and environmentally friendly biosurfactant, has broad application prospects in many industries. However, the quantitative determination of rhamnolipid is still a challenging task. Here, a new sensitive method for the quantitative analysis of rhamnolipid based on a simple derivatization reaction was developed. In this study, 3-[3'-(l-rhamnopyranosyloxy) decanoyloxy] decanoic acid (Rha-C10-C10) and 3-[3'-(2'-O-α-l-rhamnopyranosyloxy) decanoyloxy] decanoic acid (Rha-Rha-C10-C10) were utilized as the representative rhamnolipids. Liquid chromatography-mass spectrometry and high-performance liquid chromatography-ultra violet results showed that these two compounds were successfully labeled with 1 N1-(4-nitrophenyl)-1,2-ethylenediamine. There was an excellent linear relationship between rhamnolipid concentration and peak area of labeled rhamnolipid. The detection limits of the Rha-C10-C10 and Rha-Rha-C10-C10 were 0.018 mg/L (36 nmol/L) and 0.014 mg/L (22 nmol/L), respectively. The established amidation method was suitable for the accurate analysis of rhamnolipids in the biotechnological process. The method had good reproducibility with the relative standard deviation of 0.96% and 0.79%, respectively, and sufficient accuracy with a recovery of 96%-100%. This method was applied to quantitative analysis of 10 rhamnolipid homologs metabolized by Pseudomonas aeruginosa LJ-8. The single labeling method was used for the quantitative analysis of multiple components, which provided an effective method for the quality evaluation of other glycolipids with carboxyl groups.


Assuntos
Biotecnologia , Glicolipídeos , Cromatografia Líquida de Alta Pressão , Reprodutibilidade dos Testes , Glicolipídeos/metabolismo , Pseudomonas aeruginosa , Tensoativos/química
8.
Biotechnol Appl Biochem ; 70(1): 238-248, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35419893

RESUMO

Surfactin, which is composed of a ß-hydroxy fatty acid chain and a peptide ring, has drawn considerable attention due to its potential applications in the biomedicine, bioremediation, and petroleum industries. However, the low yield of surfactin from wild strains still restricts its industrial applications. In this study, eight genes relevant to the fatty acid biosynthesis pathway were targeted to enhance surfactin production, and high surfactin-yielding strains with potential industrial applications were obtained. When ldeHA and acc were co-overexpressed, the surfactin yield of recombinant strains TDS8 and TPS8 increased to 1.55- and 1.19-fold of their parental strains, respectively, again proving that the conversion of acetyl-coenzyme A (CoA) to malonyl-CoA is the rate-limiting step in fatty acid biosynthesis. Furthermore, changes in surfactin isoforms of recombinant strain TPS8 suggest that the fatty acid precursor synthesis pathway can be modified to improve the proportion of different isoforms. In addition, the deletion of lpdV, which is responsible for the conversion of α-ketoacyl-CoA precursors, resulted in a sharp decrease in surfactin production, further demonstrating the importance of branched-chain fatty acid biosynthesis in surfactin production. This work will facilitate the design and construction of more efficiently engineered strains for surfactin production and further extend industrial applications.


Assuntos
Bacillus subtilis , Ácidos Graxos , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Ácidos Graxos/metabolismo , Engenharia Genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Lipopeptídeos/genética , Lipopeptídeos/metabolismo , Peptídeos Cíclicos/genética , Peptídeos Cíclicos/metabolismo
9.
Environ Microbiol ; 24(7): 3063-3080, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35254697

RESUMO

The recently proposed order Candidatus Thermoprofundales, currently containing only one family-level lineage Marine Benthic Group-D (MBG-D), is distributed in global subsurface ecosystems and ecologically important, but its diversity, evolution and metabolism remain largely unknown. Here we described two novel family-level specialized lineages in Ca. Thermoprofundales, JdFR-43 and HyVt, which are restricted to specific biotopes (primarily in marine hydrothermal vents and occasionally in oil reservoirs and hot springs) in contrast to the cosmopolitan lineage MBG-D. The comparative genomics revealed that the specialized lineages have streamlined genomes, higher GC contents, enriched genes associated with nucleotide biosynthesis, ribosome biogenesis and DNA repair and additional thermostable aminopeptidases, enabling them to adapt to high-temperature habitats such as marine hydrothermal vents, deep subsurface oil reservoirs and hot springs. On the contrary, the unique metabolic traits of the cosmopolitan MBG-D, motility, glycolysis, butanoate metabolism, secondary metabolites production and additional genes for specific peptides and carbohydrates degradation potentially enhance its response to environmental change. Substrate preference is found for most MAGs across all lineages with the ability to utilize both polysaccharides (chitin and starch) and proteinaceous substances, whereas JdFR-43 members from oil reservoirs can only utilize proteins. These results expand the diversity of Ca. Thermoprofundales significantly and further improve our understandings of the adaptations of Ca. Thermoprofundales to various environments.


Assuntos
Fontes Termais , Fontes Hidrotermais , Archaea/genética , Ecossistema , Filogenia
10.
J Basic Microbiol ; 62(11): 1319-1336, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35048396

RESUMO

Polysaccharides are biobased polymers obtained from renewable sources. They exhibit various interesting features including biocompatibility, biodegradability, and nontoxicity. Microbial polysaccharides are produced by several microorganisms including yeast, fungi, algae, and bacteria. Microbial polysaccharides have gained high importance in biotechnology due to their novel physiochemical characteristics and composition. Among microbial polysaccharides, xanthan, alginate, gellan, and dextran are the most commonly reported polysaccharides for the development of biomimetic materials for biomedical applications including targeted drug delivery, wound healing, and tissue engineering. Several chemical and physical cross-linking reactions are performed to increase their technological and functional properties. Owning to the broad-scale applications of microbial polysaccharides, this review aims to summarize the characteristics with different ways of physical/chemical crosslinking for polysaccharide regulation. Recently, several biopolymers have gained high importance due to their biologically active properties. This will help in the formation of bioactive nutraceuticals and functional foods. This review provides a perspective on microbial polysaccharides, with special emphasis given to applications in promising biosectors and the subsequent advancement on the discovery and development of new polysaccharides for adding new products.


Assuntos
Polissacarídeos , Engenharia Tecidual , Sistemas de Liberação de Medicamentos , Polímeros , Alginatos , Biopolímeros
11.
Int Ophthalmol ; 42(3): 981-988, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34642840

RESUMO

PURPOSE: To analyze functions of corneal biomechanical properties (CBP)-related variants as corneal resistance factor (CRF) and corneal hysteresis (CH). METHODS: Related single nucleotide polymorphisms (SNPs) and genes were identified from NHGRI-EBI GWAS catalog, GWASdb v2 and possible data in published studies. HaploReg v4.1 was used to find linkage SNPs. Functional annotations were performed by GWAVA, CADD and RegulomeDB. GTEx Portal database was used to find out expression quantitative trait locus (eQTL) association. Enrichr was used to annotate the function of GWAS gene and the associated signal pathway. STING (v11.0) database was utilized for protein interaction and network construction. RESULTS: The integration of 302 CH-associated and 420 CRF-associated lead SNPs has produced 531 CBP-associated lead SNPs. A total of 5,324 proxy variants identified using the HaploReg v4.1 and lead SNPs were functionally annotated. Based on the threshold (CADD ≥ 10, GWAVA ≥ 0.4 and RegulomeDB < rank 3), 23 prioritized putative regulatory SNPs were identified. Eight prioritized eQTL variants (rs75203695, rs34861673, rs846766, rs11024102, rs1377416, rs3829492, rs9934438 and rs197912) were found with strong potential of CBP regulation. It was indicated that CBP-associated genes were significantly enriched in extracellular matrix receptor interaction pathway, closely related to the phenotype of corneal dystrophy and keratoconus. COL1A1, SMAD3, BMP4 and RUNX2 occupied the core position in the co-expression network. CONCLUSIONS: Data integrative analysis can evaluate CBP variations and explore collagen and extracellular matrix pathways in CBP regulation, which is a promising tool to investigate biological process of corneal diseases.


Assuntos
Fenômenos Biomecânicos , Córnea , Polimorfismo de Nucleotídeo Único , Biologia Computacional , Estudo de Associação Genômica Ampla , Humanos , Locos de Características Quantitativas
12.
Angew Chem Int Ed Engl ; 61(38): e202208861, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-35880539

RESUMO

We report the development of bifunctional trifluoromethylsilyl reagents for selective trifluoromethylation. The newly developed reagent, Me2 (CH2 Cl)SiCF3 , allows highly enantioselective trifluoromethylations of ketones with broad scope. Notably, by taking advantage of the chloromethyl group, a tandem synthesis of chiral trifluoromethylated oxasilacyclopentanes is developed, paving way to α-CF3 tertiary alcohols with vicinal tertiary or quaternary stereocenters. Theoretical studies revealed the important role of nonclassical C-H⋅⋅⋅F-C interactions in stabilizing the transition state, and that the presence of the chlorine atom enhances such interactions for better enantiofacial control.

13.
Mol Plant Microbe Interact ; 34(12): 1446-1449, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34445887

RESUMO

Erysiphe necator is an economically important biotrophic fungal pathogen responsible for powdery mildew disease on grapevine. Currently, genome sequences are available for only a few E. necator isolates from the United States. Based on the combination of Nanopore and Illumina sequencing technologies, we present here the complete genome assembly for an isolate of E. necator, NAFU1, identified in China. We acquired a total of 15.93 Gb of raw reads. These reads were processed into a 61.12-Mb genome assembly containing 73 contigs with an N50 of 2.06 Mb and a maximum length of 6.05 Mb. Combining the results of three gene-prediction modules (i.e., an evidence-based gene modeler [EVidenceModeler], an ab initio gene modeler, and a homology-based gene modeler), we predicted 7,235 protein-coding genes in the assembled genome of E. necator NAFU1. This information will facilitate studies of genome evolution and pathogenicity mechanisms of E. necator and other powdery mildew species through comparative genome sequence analysis and other molecular genetic tools.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Ascomicetos , Vitis , Erysiphe , Doenças das Plantas
14.
New Phytol ; 230(5): 2029-2046, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33595857

RESUMO

Calcium-dependent protein kinases (CDPKs) play vital roles in metabolic regulations and stimuli responses in plants. However, little is known about their function in grapevine. Here, we report that VpCDPK9 and VpCDPK13, two paralogous CDPKs from Vitis pseudoreticulata accession Baihe-35-1, appear to positively regulate powdery mildew resistance. The transcription of them in leaves of 'Baihe-35-1' were differentially induced upon powdery mildew infection. Overexpression of VpCDPK9-YFP or VpCDPK13-YFP in the V. vinifera susceptible cultivar Thompson Seedless resulted in enhanced resistance to powdery mildew (YFP, yellow fluorescent protein). This might be due to elevation of SA and ethylene production, and excess accumulation of H2 O2 and callose in penetrated epidermal cells and/or the mesophyll cells underneath. Ectopic expression of VpCDPK9-YFP in Arabidopsis resulted in varied degrees of reduced stature, pre-mature senescence and enhanced powdery mildew resistance. However, these phenotypes were abolished in VpCDPK9-YFP transgenic lines impaired in SA signaling (pad4sid2) or ethylene signaling (ein2). Moreover, both of VpCDPK9 and VpCDPK13 were found to interact with and potentially phosphorylate VpMAPK3, VpMAPK6, VpACS1 and VpACS2 in vivo (ACS, 1-aminocyclopropane-1-carboxylic acid (ACC) synthase; MAPK, mitogen-activated protein kinase). These results suggest that VpCDPK9 and VpCDPK13 contribute to powdery mildew resistance via positively regulating SA and ethylene signaling in grapevine.


Assuntos
Arabidopsis , Ascomicetos , Vitis , Arabidopsis/genética , China , Resistência à Doença/genética , Doenças das Plantas , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Proteínas Quinases/genética , Vitis/genética
15.
J Org Chem ; 86(13): 9206-9217, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34126743

RESUMO

An unprecedented catalyst-free reaction of benzo[b]thiophene-2,3-diones with difluoroenoxysilanes has been developed using either MeOH or H2O as the solvent, which constitutes a facile and efficient protocol for the solvent-controlled divergent synthesis of five- and seven-membered S-heterocycles featuring a gem-difluoromethylene group. A gram-scale synthesis and the diversification of the product transformations to other difluorinated S-heterocycles further highlight its utility.


Assuntos
Solventes , Catálise
16.
Bioorg Med Chem Lett ; 41: 127881, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33662541

RESUMO

Inhibition of cdc2-like kinase1 (CLK1) could efficiently induce autophagy and it has been thought as a potential target for treatment of autophagy-related diseases. Herein we report the discovery of a series of 3,6-disubstutited-imidazo[1,2-a]pyridine derivatives as a new class of CLK1 inhibitors. Among them, compound 9e is the most potent one, which exhibits an IC50 value of 4 nM against CLK1 kinase. In vitro, this compound reduces the phosphorylation level of the typical downstream substrates of CLK1 and affects their subcellular redistribution. Further study indicates that 9e is efficient to induce autophagy. Overall, this study provides a promising lead compound for drug discovery targeting CLK1 kinase.


Assuntos
Inibidores Enzimáticos/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/antagonistas & inibidores , Sítios de Ligação , Inibidores Enzimáticos/química , Humanos , Estrutura Molecular , Ligação Proteica
17.
Anal Biochem ; 600: 113746, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32333904

RESUMO

Metabolite profiling in anaerobic alkane biodegradation plays an important role in revealing activation mechanisms. Apart from alkylsuccinates, which are considered to be the usual biomarkers via fumarate addition, the downstream metabolites of C-skeleton rearrangement can also be regarded as biomarkers. However, it is difficult to detect intermediate metabolites in both environmental samples and enrichment cultures, resulting in lacking direct evidence to prove the occurrence of fumarate addition pathway. In this work, a synthetic method of rearrangement metabolites was established. Four compounds, namely, propylmalonic acid, 2-(2-methylbutyl)malonic acid, 2-(2-methylpentyl)malonic acid and 2-(2-methyloctyl)malonic acid, were synthesized and determined by four derivatization approaches. Besides, their mass spectra were obtained. Four characteristic ions were observed at m/z 133 + 14n, 160 + 28n, 173 + 28n and [M - (45 + 14n)]+ (n = 0 and 2 for ethyl and n-butyl esters, respectively). For methyl esterification, mass spectral features were m/z 132, 145 and [M - 31]+, while for silylation, fragments were m/z 73, 147, 217, 248, 261 and [M - 15]+. These data provide basis on identification of potential rearrangement metabolites in anaerobic alkane biodegradation via fumarate addition.


Assuntos
Alcanos/metabolismo , Fumaratos/metabolismo , Malonatos/metabolismo , Alcanos/química , Anaerobiose , Fumaratos/química , Malonatos/química , Espectrometria de Massas
18.
Langmuir ; 36(9): 2349-2356, 2020 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-32045250

RESUMO

Microemulsions have found a wide range of applications exploiting their chemical and physical properties. Development of microfluidic-based approaches has allowed for the controlled production of highly monodispersed emulsions, including the formation of multiple and hierarchical emulsions. Conventional poly(dimethylsiloxane)-based microfluidic systems require tight spatial control over the surface chemistry when used for double emulsion generation, which can be challenging to achieve on the micrometer scale. Here, we present a two-dimensional device design, which can selectively be surface-treated in a straightforward manner and allows for the formation of uniform water/oil/water double emulsions by combining two distinct hydrophilic and hydrophobic surface properties. These surfaces are sufficiently separated in space to allow for imparting their functionalization without the requirement for lithographic approaches or complex flow control. We demonstrate that a mismatch between the wettability requirements of the continuous phase and the channel wall inherent in this approach can be tolerated over several hundreds of micrometers, opening up the possibility to use simple pressure-driven flows to achieve surface functionalization. The design architecture exhibits robust efficiency in emulsion generation while retaining simple device fabrication. We finally demonstrate the potential of this approach by generating water in oil in water emulsions with lipid molecules acting as surfactants.

19.
Environ Sci Technol ; 54(17): 10610-10620, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32786606

RESUMO

Microbial anaerobic alkane degradation is a key process in subsurface oil reservoirs and anoxic environments contaminated with petroleum, with a major impact on global carbon cycling. However, the thermophiles capable of water-insoluble paraffins (>C17) degradation under methanogenic conditions has remained understudied. Here, we established thermophilic (55 °C) n-paraffins-degrading (C21-C30) cultures from an oil reservoir. After over 900 days of incubation, the even-numbered n-paraffins were biodegraded to methane. The bacterial communities are dominated by a novel class-level lineage of actinobacteria, 'Candidatus Syntraliphaticia'. These 'Ca. Syntraliphaticia'-like metagenome-assembled genomes (MAGs) encode a complete alkylsuccinate synthases (ASS) gene operon, as well as hydrogenases and formate dehydrogenase, and several enzymes potentially involved in alkyl-CoA oxidation and the Wood-Ljungdahl pathway. Metatranscriptomic analysis suggests that n-paraffins are activated via fumarate addition reaction, and oxidized into carbon dioxide, hydrogen/formate and acetate by 'Ca. Syntraliphaticia', that could be further converted to methane by the abundant hydrogenotrophic and acetoclastic methanogens. We also found a divergent methyl-CoM reductase-like complex (MCR) and a canonical MCR in two MAGs representing 'Ca. Methanosuratus' (within candidate phylum Verstraetearchaeota), indicating the capability of methane and short-chain alkane metabolism in the oil reservoir. Ultimately, this result offers new insights into the degradability and the mechanisms of n-paraffins under methanogenic conditions at high temperatures.


Assuntos
Euryarchaeota , Parafina , Alcanos , Anaerobiose , Metano , Filogenia
20.
Acta Pharmacol Sin ; 41(12): 1547-1556, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32488170

RESUMO

Cerebral ischemia/reperfusion (I/R) results in harmful consequences during ischemic stroke, especially the disruption of the blood-brain barrier (BBB), which leads to severe hemorrhagic transformation through aggravation of edema and brain hemorrhage. Our previous study demonstrated that icariside II (ICS II), which is derived from Herba Epimedii, attenuates cerebral I/R injury by inhibiting the GSK-3ß-mediated activation of autophagy both in vitro and in vivo. However, the effect of ICS II on the BBB remains unclear. Thus, in this study, we investigated the regulation of BBB integrity by ICS II after cerebral I/R injury and further explored the underlying mechanism in rats. Cerebral I/R injury was induced by middle cerebral artery occlusion (MCAO), and the treatment groups were administered ICS II at a dose of 16 mg/kg by gavage twice a day for 3 days. The results showed that ICS II effectively prevented BBB disruption, as evidenced by Evans Blue staining. Moreover, ICS II not only significantly reduced the expression of MMP2/9 but also increased TIMP1 and tight junction protein (occludin, claudin 5, and ZO 1) expression. Intriguingly, ICS II may directly bind to both MMP2 and MMP9, as evidenced by molecular docking. In addition, ICS II also inhibited cerebral I/R-induced apoptosis and ameliorated the Bax/Bcl-2 ratio and cleaved-caspase 3 level. Collectively, our findings reveal that ICS II significantly ameliorates I/R-induced BBB disruption and neuronal apoptosis in MCAO rats by regulating the MMP9/TIMP1 balance and inhibiting the caspase 3-dependent apoptosis pathway.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Isquemia Encefálica/metabolismo , Flavonoides/uso terapêutico , Metaloproteinase 9 da Matriz/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Animais , Apoptose/efeitos dos fármacos , Encéfalo/patologia , Isquemia Encefálica/etiologia , Isquemia Encefálica/patologia , Claudina-5/metabolismo , Flavonoides/metabolismo , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/patologia , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Simulação de Acoplamento Molecular , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/metabolismo , Ocludina/metabolismo , Ligação Proteica , Ratos Sprague-Dawley , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Proteína da Zônula de Oclusão-1/metabolismo
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