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1.
Planta ; 251(2): 43, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31907627

RESUMO

MAIN CONCLUSION: Co-expression and regulatory networks yield important insights into the growth-defense tradeoffs mechanism under jasmonic acid (JA) signals in Arabidopsis. Elevated defense is commonly associated with growth inhibition. However, a comprehensive atlas of the genes associated with the plant growth-defense tradeoffs under JA signaling is lacking. To gain an insight into the dynamic architecture of growth-defense tradeoffs, a coexpression network analysis was employed on publicly available high-resolution transcriptomes of Arabidopsis treated with coronatine (COR), a mimic of jasmonoyl-l-isoleucine. The genes involved in JA-mediated growth-defense tradeoffs were systematically revealed. Promoter enrichment analysis revealed the core regulatory module in which the genes underwent rapid activation, sustained upregulation after COR treatment, and mediated the growth-defense tradeoffs. Several transcription factors (TFs), including RAP2.6L, MYB44, WRKY40, and WRKY18, were identified as instantly activated components associated with pathogen and insect resistance. JA might rapidly activate RAV1 and KAN1 to repress brassinosteroid (BR) response genes, upregulate KAN1, the C2H2 TF families ZF2, ZF3, ZAT6, and STZ/ZAT10 to repress the biosynthesis, transport, and signaling of auxin to arrest growth. Independent datasets and preserved analyses validated the reproducibility of the results. Our study provided a comprehensive snapshot of genes that respond to JA signals and provided valuable resources for functional studies on the genetic modification of breeding population that exhibit robust growth and defense simultaneously.

2.
Sensors (Basel) ; 19(22)2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31766287

RESUMO

We report the γ-ray ionizing radiation response of commercial off-the-shelf (COTS) monolithic active-pixel sensors (MAPS) with different integration times and gains. The distribution of the eight-bit two-dimensional matrix of MAPS output frame images was studied for different parameter settings and dose rates. We present the first results of the effects of these parameters on the response of the sensor and establish a linear relationship between the average response signal and radiation dose rate in the high-dose rate range. The results show that the distribution curves can be separated into three ranges. The first range is from 0 to 24, which generates the first significant low signal peak. The second range is from 25 to 250, which shows a smooth gradient change with different integration times, gains, and dose rates. The third range is from 251 to 255, where a final peak appears, which has a relationship with integral time, gain, and dose rate. The mean pixel value shows a linear dependence on the radiation dose rate, albeit with different calibration constants depending on the integration time and gain. Hence, MAPS can be used as a radiation monitoring device with good precision.

3.
Bioorg Med Chem Lett ; 29(7): 912-916, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30777610

RESUMO

A new series of 3,6-diaryl-1H-pyrazolo[3,4-b]pyridine compounds have been discovered as potent anaplastic lymphoma kinase (ALK) inhibitors. The 4-hydroxyphenyl in the 6-position of 1H-pyrazolo[3,4-b]pyridine were crucial and a fluorine atom substitution could give promising inhibitory activity. The IC50 of compound 9v against ALK was up to 1.58 nM and a binding mechanism was proposed.

4.
J Agric Food Chem ; 67(5): 1360-1370, 2019 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-30640452

RESUMO

Oxathiapiprolin is one of the best active fungicides discovered for oomycetes control. To develop a fungicide candidate with a broad spectrum of activity, 22 new piperidinylthiazole derivatives were designed and synthesized. Compound 5l showed the best activity against Pseudoperonospora cubensis (Berk. et Curt.) Rostov and Phytophthora infestans in vivo with 100% and 80% of inhibition, respectively, at 1 mg/L, and 72.87% of field efficacy against P. cubensis at 1 g ai/667 m2 validated these results. Compound 5i exhibited a broad spectrum of excellent activity against Sclerotinia sclerotiorum with EC50 = 0.30 mg/L (>10 times more active than oxathiapiprolin and azoxystrobin in vitro), good activity against Botrytis cinerea, Cercospora arachidicola, and Gibberella zeae with EC50 of 14.54, 5.57, and 14.03 mg/L in vitro and against P. cubensis and P. infestans with 60% and 30% inhibition rates, respectively, at 1 mg/L in vivo. Mode of action studies by RNA sequencing analysis discovered oxysterol-binding protein (OSBP), chitin synthase (CHS1), and (1,3)-ß-glucan synthase (FKS2) as the potent target of 5i against S. sclerotiorum. Quenching studies validated that OSBP was the same target of both 5i and oxathiapiprolin; it was quenched by both of them. Our studies discovered isothiazole-containing piperidinylthiazole as an OSBP target-based novel lead for fungicide development.


Assuntos
Fungicidas Industriais/química , Fungicidas Industriais/farmacologia , Tiazóis/química , Tiazóis/farmacologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/crescimento & desenvolvimento , Botrytis/efeitos dos fármacos , Botrytis/crescimento & desenvolvimento , Cucumis sativus/microbiologia , Descoberta de Drogas , Lycopersicon esculentum/microbiologia , Phytophthora infestans/efeitos dos fármacos , Phytophthora infestans/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Relação Estrutura-Atividade
5.
J Agric Food Chem ; 67(6): 1647-1655, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30669828

RESUMO

To contribute molecular diversity for novel fungicide development, a series of novel thiazole carboxamides were rationally designed, synthesized, and characterized with the succinate dehydrogenase (SDH) as target. Bioassay indicated that compound 6g showed the similar excellent SDH inhibition as that of Thifluzamide with IC50 of 0.56 mg/L and 0.55 mg/L, respectively. Some derivatives displayed improved in vitro fungicidal activities against Rhizoctonia cerealis and Sclerotinia sclerotiorum with EC50 of 1.2-16.4 mg/L and 0.5-1.9 mg/L. Surprisingly, 6g showed promising in vitro fungicidal activities against R. cerealis and S. sclerotiorum with EC50 of 6.2 and 0.6 mg/L, respectively, which was superior to Thifluzamide with the EC50 of 22.1 and 4.4 mg/L, respectively. Additionally, compounds 6c and 6g displayed excellent in vivo fungicidal activities against S. sclerotiorum on Brassica napus L. leaves with protective activity of 75.4% and 67.3% at 2.0 mg/L, respectively, while Thifluzamide without activity at 5.0 mg/L. Transcriptomic analysis of S. sclerotiorum treated with 6g by RNA sequencing indicated the down-regulation of succinate dehydrogenase gene SDHA and SDHB, and the inhibition of the TCA-cycle.


Assuntos
Inibidores Enzimáticos/farmacologia , Proteínas Fúngicas/antagonistas & inibidores , Fungicidas Industriais/farmacologia , Succinato Desidrogenase/antagonistas & inibidores , Tiazóis/farmacologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/enzimologia , Descoberta de Drogas , Inibidores Enzimáticos/química , Proteínas Fúngicas/metabolismo , Fungicidas Industriais/química , Estrutura Molecular , Rhizoctonia/efeitos dos fármacos , Rhizoctonia/enzimologia , Relação Estrutura-Atividade , Succinato Desidrogenase/metabolismo , Tiazóis/química
6.
Pest Manag Sci ; 75(1): 292-301, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29885056

RESUMO

BACKGROUND: Plant viral diseases cause tremendous decreases in yield and quality. Natural polycyclic compounds such as those containing carbocycles are often very important lead compounds for drug and pesticide development. Tricyclic spiranoid lactones with 5A 5B 6C -ring fusion topologies possess various bioactivities. In this study, 33 new 5A 5B 6C tricyclic spirolactones were rationally designed, synthesized, characterized and evaluated for antiviral activities. RESULT: These compounds showed no apparent toxicity against Italian honeybees up to 2.73 µg bee-1 . Spirolactones 14, 16, 19, 23 and 28 at a concentration of 100 µg mL-1 inactivated 90% of tobacco mosaic virus (TMV) infection, making these compounds much more potent than the positive controls. Significantly, compound 19 displayed the best inactivation activity causing inhibition of up to 98%. CONCLUSION: The results of the bioassays and QSAR studies indicated that the carbon-containing cyclic moiety was the antiviral pharmacophore, and derivative 19, which showed the best inactivation activity, could emerge as a potential antiviral agent against TMV. In vitro capsid protein (CP) assembly and TMV assembly inhibition determinations indicated that these compounds induced crosslinking in the TMV and prevented its uncoating, which was a putative new mode of action for TMV inactivation. © 2018 Society of Chemical Industry.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Espironolactona/síntese química , Espironolactona/farmacologia , Animais , Antivirais/química , Antivirais/toxicidade , Abelhas/efeitos dos fármacos , Proteínas do Capsídeo/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Relação Quantitativa Estrutura-Atividade , Espironolactona/química , Espironolactona/toxicidade , Vírus do Mosaico do Tabaco/efeitos dos fármacos , Montagem de Vírus/efeitos dos fármacos
7.
J Agric Food Chem ; 66(46): 12439-12452, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30350975

RESUMO

Target identification is an essential basis for novel-pesticide development in new molecular design and lead optimization. 3-(4-Methyl-1,2,3-thiadiazolyl)-6-trichloromethyl[1,2,4]triazolo[3,4- b][1,3,4]thiadizole (YZK-C22) is a novel fungicide candidate with specific antifungal activity. We investigated its mode of action, and our studies indicated that YZK-C22 showed no cross resistance against Saccharomyces cerevisiae mutants with classic fungicide targets. Mec1 and Rad53 are two kinases that respond to DNA-replication damage, and the efficacy test showed that YZK-C22 could not perform its fungicidal activity by inhibiting DNA repair. Target screening by drug-affinity-responsive target stability (DARTS) showed that pyruvate kinase (PK), a key enzyme in the glycolytic pathway, was the potent new fungicidal target of YZK-C22. Fifty-eight differentially expressed proteins (DEPs) primarily involved in the metabolic process were identified by isobaric tags for relative and absolute quantification analysis (iTRAQ) in S. cerevisiae, and protein expression in the citrate cycle decreased with treatment of 5 mg/L YZK-C22, which was consistent with the results of DARTS. Molecular-docking analysis further validated that YZK-C22 could dock into the active center of PK instead of phosphoenolpyruvate. The enzyme activity of PK from S. cerevisiae was competitively inhibited with a Ki of 3.33 ± 0.28 µmol/L, and the cell-growth inhibition of S. cerevisiae was released by supplementation with pyruvic acid, whereas the growth of S. cerevisiae was not recovered by adding PK's substrate (phosphoenolpyruvate) or allosteric regulator (fructose-1,6-bisphosphate). The present studies uncovered and validated the primary target of the new, potent fungicidal candidate YZK-C22; our results provide a successful, valuable, and applicable case of target discovery and identification for novel-fungicide development.


Assuntos
Inibidores Enzimáticos/química , Fungicidas Industriais/química , Piruvato Quinase/antagonistas & inibidores , Proteínas de Saccharomyces cerevisiae/antagonistas & inibidores , Saccharomyces cerevisiae/efeitos dos fármacos , Tiadiazóis/química , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Fungicidas Industriais/farmacologia , Cinética , Simulação de Acoplamento Molecular , Piruvato Quinase/genética , Piruvato Quinase/metabolismo , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Tiadiazóis/farmacologia
8.
J Agric Food Chem ; 66(28): 7319-7327, 2018 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-29913064

RESUMO

A molecular design approach was used in our laboratory to guide the development of imidazole-based fungicides. Based on homology modeling and molecular docking studies targeting the cytochrome P450-dependent sterol 14α-demethylase, 3,4-dichloroisothiazole-based imidazoles showed great potential. Several such compounds were then rationally designed, synthesized, characterized, and their antifungal activities were evaluated. Bioassay results showed that compounds such as ( R)-11, ( R)-12, and ( S)-11 have commendable, broad-spectrum antifungal activities that are comparable to those of commercial products. Based on Q-PCR testing and microscopy observations, the imidazole derivatives affect fungal cell wall formation through the inhibition of the BcCYP51 expression system. These findings strongly suggest that the mode of action of these imidazole compounds is similar to that of tioconazole and imazalil. This report indicates that this molecular design strategy is not only practical but productive.


Assuntos
Fungicidas Industriais/síntese química , Fungicidas Industriais/farmacologia , Imidazóis/síntese química , Imidazóis/farmacologia , Inibidores de 14-alfa Desmetilase/síntese química , Inibidores de 14-alfa Desmetilase/química , Inibidores de 14-alfa Desmetilase/farmacologia , Proteínas Fúngicas/antagonistas & inibidores , Proteínas Fúngicas/química , Fungos/efeitos dos fármacos , Fungos/enzimologia , Fungos/genética , Fungicidas Industriais/química , Imidazóis/química , Modelos Moleculares , Simulação de Acoplamento Molecular , Esterol 14-Desmetilase/química
9.
J Colloid Interface Sci ; 463: 75-82, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26520813

RESUMO

A highly selective and stable catalyst based on Pt nanoparticles confined in Mesoporous TiO2-SiO2 frameworks were prepared and employed for selective hydrogenation of cinnamaldehyde to cinnamyl alcohol. The as-prepared Pt/MesoTiO2-SiO2-M catalyst displayed excellent selectivity to cinnamyl alcohol (around 91%) at nearly complete conversion. Ti(2+) and stronger metal-support interaction (SMSI) played key roles on the adsorption behavior of cinnamaldehyde and activation of CO bonds. The existence of amorphous SiO2 and mixed TiO2 phases (anatase and rutile) was helpful for the formation of Ti(2+) sites and SMSI. The electron-enriched Pt surfaces and the formed Pt-TiOx system benefited the enhanced activity and selectivity.

10.
Org Lett ; 16(5): 1350-3, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24571784

RESUMO

Copper-catalyzed cyclization of an oxime ester toward divergent heterocycle synthesis is reported. Oxime ester serves as an enamine precursor to cyclize with malononitrile and aldehydes for access to 2-aminonicotinonitriles in a one-pot reaction, while cyclizing with N-sulfonylimines leads to synthesis of pyrazolines.


Assuntos
Cobre/química , Iodetos/química , Ácidos Nicotínicos/síntese química , Nitrilos/síntese química , Oximas/química , Pirazóis/síntese química , Catálise , Ciclização , Ésteres , Estrutura Molecular , Ácidos Nicotínicos/química , Nitrilos/química , Pirazóis/química
11.
Wei Sheng Wu Xue Bao ; 45(2): 258-63, 2005 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-15989272

RESUMO

The psychrotrophs SYP-A2-3 producing the cold-adapted protease has been isolated from the bacterial samples collected from the No. 1 Glacier of China and identified as Bacillus cereus according to its morphological and physiochemical characteristics and 16s rDNA gene sequence analysis. It could grow between 0 degree C and 38 degrees C while its optimal growth temperature was 25 degrees C and the optimal temperature for its protease production was 15 degrees C. The cold-adapted protease was identified as neutral metallo-protease, the molecular weight was 34.2 kD shown by SDS-PAGE, the optimal pH and temperature for activity was 7.0-8.5 and 42 degrees C, respectively. Various fermentation conditions of its protease production were also investigated. The results showed that casein was the best nitrogen source while glucose and starch were suitable carbon source for its protease production. The initial pH of fermentation broth ranged from 6.5 to 7.0 was optimal. Under optimized conditions, the protease activity produced by SYP-A2-3 could reach 3800 U/mL and 4800 U/mL conducted in shaking flask and 5 L stirred jar experiment, respectively.


Assuntos
Bacillus cereus/classificação , Bacillus cereus/enzimologia , Metaloproteases/biossíntese , Bacillus cereus/crescimento & desenvolvimento , Bacillus cereus/isolamento & purificação , Meios de Cultura , Estabilidade Enzimática , Fermentação , Concentração de Íons de Hidrogênio , Metaloproteases/química , Metaloproteases/metabolismo , Peso Molecular , Temperatura Ambiente
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