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1.
Biosci Biotechnol Biochem ; 84(1): 178-186, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31581931

RESUMO

Prohydrojasmon has been reported to improve the quality of crops. However, most previous studies have investigated its application on fruits. Here, we evaluated the effect of prohydrojasmon on the growth and total phenolic content, anthocyanin content, and antioxidant activity in komatsuna (Brassica rapa var. periviridis) and lettuce (Lactuca sativa L.). Prohydrojasmon did not show any serious inhibitory effect. Prohydrojasmon applied to komatsuna at a concentration of 0.5 µM significantly increased the total phenolic content and anthocyanin content, and a concentration of 1 µM increased the antioxidant activity. In lettuce, prohydrojasmon at a concentration of 400 µM significantly increased the total phenolic content and anthocyanin content, while a concentration of 0.5 µM significantly increased the antioxidant activity. These results suggest that prohydrojasmon positively affects the phenolic compound and anthocyanin accumulation and antioxidant activity in komatsuna and lettuce without adversely affecting growth.


Assuntos
Antocianinas/metabolismo , Antioxidantes/metabolismo , Brassica rapa/efeitos dos fármacos , Ciclopentanos/farmacologia , Alface/efeitos dos fármacos , Oxilipinas/farmacologia , Reguladores de Crescimento de Planta/farmacologia , Polifenóis/metabolismo , Brassica rapa/crescimento & desenvolvimento , Ciclopentanos/síntese química , Alface/crescimento & desenvolvimento , Oxilipinas/síntese química , Compostos Fitoquímicos/síntese química , Compostos Fitoquímicos/farmacologia , Reguladores de Crescimento de Planta/síntese química , Polifenóis/farmacologia , Transdução de Sinais/efeitos dos fármacos , Verduras/efeitos dos fármacos
2.
J Agric Food Chem ; 67(49): 13509-13517, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31725280

RESUMO

In this study, novel water-soluble quaternary ammonium salts of iminofullerenes (IFQA) were synthesized by nitrene chemistry in combination with quaternization and identified as [C60(NCH2CH2NH3+·CF3COO-)4·10H2O]n by various spectroscopies. Maize and Arabidopsis seeds were used to test the bioactivity of IFQA in seed germination. Compared with the control, maize seed exposure to 50 mg/L IFQA (normal: 73.1% vs 58.7%; drought: 66.7% vs 50.0% at the second day) and Arabidopsis seed exposure to 20 mg/L IFQA (normal: 77.5% vs 58.8%; drought: 63.3% vs 36.7% at the second day) had higher germination rates and quicker germination. The results of two-dimensional gel electrophoresis combined with mass spectroscopy showed that the abundance of 21 proteins in embryo proteome of maize seeds was significantly changed (>1.5 fold). The downregulated six storage proteins and upregulated four proteins induced by IFQA for energy production and sugar metabolism indicated a faster metabolic activity of maize seed germination. The upregulated eight stress-related proteins and antioxidant enzymes suggested that the role of IFQA was to activate the metabolic processes in seed germination and also increase seed stress response. The results provide important information to understand the mechanism of seed germination enhancement by carbon nanomaterials.


Assuntos
Compostos de Amônio/farmacologia , Arabidopsis/crescimento & desenvolvimento , Fulerenos/farmacologia , Reguladores de Crescimento de Planta/farmacologia , Sementes/efeitos dos fármacos , Triticum/crescimento & desenvolvimento , Compostos de Amônio/química , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/metabolismo , Fulerenos/química , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Germinação/efeitos dos fármacos , Reguladores de Crescimento de Planta/síntese química , Reguladores de Crescimento de Planta/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Triticum/efeitos dos fármacos , Triticum/genética , Triticum/metabolismo
3.
N Biotechnol ; 48: 76-82, 2019 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-30077756

RESUMO

Strigolactones (SLs) constitute a new class of plant hormones of increasing importance in plant science. The structure of natural SLs is too complex for ready access by synthesis. Therefore, much attention is being given to design of SL analogues and mimics with a simpler structure but with retention of bioactivity. Here new hybrid type SL mimics have been designed derived from auxins, the common plant growth regulators. Auxins were simply coupled with the butenolide D-ring using bromo (or chloro) butenolide. D-rings having an extra methyl group at the vicinal C-3' carbon atom, or at the C-2' carbon atom, or at both have also been studied. The new hybrid type SL mimics were bioassayed for germination activity of seeds of the parasitic weeds S. hermonthica, O. minor and P. ramosa using the classical method of counting germinated seeds and a colorimetric method. For comparison SL mimics derived from phenyl acetic acid were also investigated. The bioassays revealed that mimics with a normal D-ring had appreciable to good activity, those with an extra methyl group at C-2' were also appreciably active, whereas those with a methyl group in the vicinal C-3' position were inactive (S. hermonthica) or only slightly active. The new hybrid type mimics may be attractive as potential suicidal germination agents in agronomic applications.


Assuntos
Materiais Biomiméticos/química , Ácidos Indolacéticos/química , Lactonas/química , Reguladores de Crescimento de Planta/química , Materiais Biomiméticos/síntese química , Materiais Biomiméticos/farmacologia , Desenho de Drogas , Estabilidade de Medicamentos , Germinação/efeitos dos fármacos , Ácidos Indolacéticos/síntese química , Ácidos Indolacéticos/farmacologia , Lactonas/síntese química , Lactonas/farmacologia , Estrutura Molecular , Reguladores de Crescimento de Planta/síntese química , Reguladores de Crescimento de Planta/farmacologia , Plantas Daninhas/efeitos dos fármacos , Plantas Daninhas/crescimento & desenvolvimento
4.
Chemistry ; 25(14): 3496-3500, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30589135

RESUMO

The PYR/PYL/RCAR protein families have recently emerged as receptors of the phytohormone abscisic acid (ABA, 1), which regulates plant responses to environmental stress. These families have multiple members with different physiological actions, and so selective agonists or antagonists are needed both as tools to elucidate functional differences and as lead compounds for agrochemicals. We previously identified RK460 (rac-3 a) as a PYR1-selective antagonist, and showed that it possesses five stereocenters on a 6,5-cis-bicyclo skeleton. Here, we synthesized all the stereoisomers of RK460 and evaluated their activity towards a panel of receptors. Relative stereochemistry as well as absolute stereochemistry was important for selective action.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/antagonistas & inibidores , Arabidopsis/efeitos dos fármacos , Compostos Bicíclicos com Pontes/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Reguladores de Crescimento de Planta/metabolismo , Receptores de Superfície Celular/antagonistas & inibidores , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Compostos Bicíclicos com Pontes/síntese química , Compostos Bicíclicos com Pontes/química , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Reguladores de Crescimento de Planta/síntese química , Reguladores de Crescimento de Planta/química , Receptores de Superfície Celular/metabolismo , Estereoisomerismo
5.
Org Biomol Chem ; 16(38): 6860-6864, 2018 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-30226251

RESUMO

The plant hormone conjugate 2-O-(indole-3-acetyl)-myo-inositol (IAInos) has been selectively prepared for the first time by two routes from myo-inositol. One of the syntheses depended upon the construction of the 3-indoleacetyl group by a Fischer indole synthesis on an unreactive axial hydroxyl group, while the other via a direct acylation of the equatorially orientated hydroxy group created by conformational constraint of the cyclohexane ring. The latter synthesis produced IAInos in 5 steps and 29% overall yield.


Assuntos
Ácidos Indolacéticos/síntese química , Indóis/síntese química , Inositol/síntese química , Reguladores de Crescimento de Planta/síntese química , Acilação , Técnicas de Química Sintética , Ácidos Indolacéticos/química , Indóis/química , Inositol/análogos & derivados , Reguladores de Crescimento de Planta/química
6.
Planta ; 248(5): 1049-1062, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30069731

RESUMO

MAIN CONCLUSION: Gibberellic acid is a plant growth hormone that promotes cell expansion and division. Studies have aimed at optimizing and reducing production costs, which could make its application economically viable for different cultivars. Gibberellins consist of a large family of plant growth hormones discovered in the 1930s, which are synthesized via the terpenes route from the geranylgeranyl diphosphate and feature a basic structure formed by an ent-gibberellane tetracyclic skeleton. Among them, only four have biological activity, including gibberellic acid (GA3), which acts as a natural plant growth regulator, especially for stem elongation, seed germination, and increased fruit size. It can be obtained from plants, fungi, and bacteria. There are also some reports about microalgae GA3 producers. Fungi, especially Gibberella fujikuroi, are preferred for GA3 production via submerged fermentation or solid-state fermentation. Many factors may affect its production, some of which are related to the control and scale-up of fermentation parameters. Different GA3 products are available on the market. They can be found in liquid or solid formulations containing only GA3 or a mixture of other biological active gibberellins, which can be applied on a wide variety of cultivars, including crops and fruits. However, the product's cost still limits its large and continuous application. New low-cost and efficient GA3 production alternatives are surely welcome. This review deals with the latest scientific and technological advances on production, recovery, formulation, and applications of this important plant growth hormone.


Assuntos
Giberelinas/síntese química , Reguladores de Crescimento de Planta/síntese química , Biotecnologia/métodos , Fermentação , Giberelinas/química , Giberelinas/isolamento & purificação , Reguladores de Crescimento de Planta/química , Reguladores de Crescimento de Planta/isolamento & purificação
7.
ACS Chem Biol ; 13(9): 2585-2594, 2018 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-30138566

RESUMO

Indole-3-acetic acid (auxin) is considered one of the cardinal hormones in plant growth and development. It regulates a wide range of processes throughout the plant. Synthetic auxins exploit the auxin-signaling pathway and are valuable as herbicidal agrochemicals. Currently, despite a diversity of chemical scaffolds all synthetic auxins have a carboxylic acid as the active core group. By applying bio-isosteric replacement we discovered that indole-3-tetrazole was active by surface plasmon resonance spectrometry, showing that the tetrazole could initiate assembly of the Transport Inhibitor Resistant 1 (TIR1) auxin coreceptor complex. We then tested the tetrazole's efficacy in a range of whole plant physiological assays and in protoplast reporter assays, which all confirmed auxin activity, albeit rather weak. We then tested indole-3-tetrazole against the AFB5 homologue of TIR1, finding that binding was selective against TIR1, absent with AFB5. The kinetics of binding to TIR1 are contrasted to those for the herbicide picloram, which shows the opposite receptor preference, as it binds to AFB5 with far greater affinity than to TIR1. The basis of the preference of indole-3-tetrazole for TIR1 was revealed to be a single residue substitution using molecular docking, and assays using tir1 and afb5 mutant lines confirmed selectivity in vivo. Given the potential that a TIR1-selective auxin might have for unmasking receptor-specific actions, we followed a rational design, lead optimization campaign, and a set of chlorinated indole-3-tetrazoles was synthesized. Improved affinity for TIR1 and the preference for binding to TIR1 was maintained for 4- and 6-chloroindole-3-tetrazoles, coupled with improved efficacy in vivo. This work expands the range of auxin chemistry for the design of receptor-selective synthetic auxins.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas F-Box/metabolismo , Herbicidas/metabolismo , Ácidos Indolacéticos/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Receptores de Superfície Celular/metabolismo , Tetrazóis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Halogenação , Herbicidas/síntese química , Herbicidas/química , Ácidos Indolacéticos/síntese química , Ácidos Indolacéticos/química , Simulação de Acoplamento Molecular , Reguladores de Crescimento de Planta/síntese química , Reguladores de Crescimento de Planta/química , Ligação Proteica , Tetrazóis/síntese química , Tetrazóis/química
8.
J Sci Food Agric ; 98(13): 5129-5133, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29635793

RESUMO

BACKGROUND: The present investigation reports the stimulating effects of different substituted alkyl silatranes (3a-3e) on the early seedling growth of wheat (Triticum aestivum) and maize (Zea mays). Seeds of these plants were exposed to six different concentrations (0, 10, 50, 100, 200 and 500 µmol L-1 ). The results revealed that different substitutions (3a-3e) had different effects on root and shoot elongation. Silatranes (3a-3e) were synthesized employing microwave irradiation by a solvent-mediated transesterification reaction, thereby reducing reaction times from several hours under conventional reflux conditions to 15 min under microwave irradiation. RESULTS: It was of interest that the effect of these silatranes did not show a dose-dependent relationship but an optimum concentration, which was 100 µmol L-1 for maize and 200 µmol L-1 for wheat. γ-Aminopropyl silatranes (3b and 3e) gave the best results in maize, whereas γ-chloropropyl silatrane (3a) was most efficient for wheat at these optimum concentrations. CONCLUSION: All the synthesized silatranes were effective in promoting root and shoot growth of wheat and maize. Furthermore, an efficient green microwave methodology was successful for the synthesis of silatranes. These observations pave the way for silatranes as efficient plant growth regulators for crops. © 2018 Society of Chemical Industry.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos de Organossilício/farmacologia , Reguladores de Crescimento de Planta/farmacologia , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento , Triticum/efeitos dos fármacos , Zea mays/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/síntese química , Compostos de Organossilício/síntese química , Reguladores de Crescimento de Planta/síntese química , Raízes de Plantas/efeitos dos fármacos , Brotos de Planta/efeitos dos fármacos , Triticum/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento
9.
J Exp Bot ; 69(9): 2205-2218, 2018 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-29385517

RESUMO

The development and growth of plants are regulated by interplay of a plethora of complex chemical reactions in which plant hormones play a pivotal role. In recent years, a group of new plant hormones, namely strigolactones (SLs), was discovered and identified. The first SL, strigol, was isolated in 1966, but it took almost 20 years before the details of its structure were fully elucidated. At present, two families of SLs are known, one having the stereochemistry of (+)-strigol and the other that of (-)-orobanchol, the most abundant naturally occurring SL. The most well-known bioproperty of SLs is the germination of seeds of the parasitic weeds Striga and Orobanche. It is evident that SLs are going to play a prominent role in modern molecular botany. In this review, relevant molecular and bioproperties of SLs are discussed. Items of importance are the effect of stereochemistry, structure-activity relationships, design and synthesis of analogues with a simple structure, but with retention of bioactivity, introduction of fluorescent labels into SLs, biosynthetic origin of SLs, mode of action in plants, application in agriculture for the control of parasitic weeds, stimulation of the branching of arbuscular mycorrhizal (AM) fungi, and the control of plant architecture. The future potential of SLs in molecular botany is highlighted.


Assuntos
Lactonas/química , Micorrizas/fisiologia , Reguladores de Crescimento de Planta/química , Fenômenos Fisiológicos Vegetais , Controle de Plantas Daninhas , Lactonas/síntese química , Desenvolvimento Vegetal , Reguladores de Crescimento de Planta/síntese química , Plantas Daninhas , Estereoisomerismo , Relação Estrutura-Atividade
10.
Molecules ; 22(12)2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29244719

RESUMO

2',3'-iso-Benzoabscisic acid (iso-PhABA), an excellent selective abscisic acid (ABA) analog, was developed in our previous work. In order to find its more structure-activity information, some structural modifications were completed in this paper, including the substitution of phenyl ring and replacing the ring with heterocycles. Thus, 16 novel analogs of iso-PhABA were synthesized and screened with three bioassays, Arabidopsis and lettuce seed germination and rice seedling elongation. Some of them, i.e., 2',3'-iso-pyridoabscisic acid (iso-PyABA) and 2',3'-iso-franoabscisic acid (iso-FrABA), displayed good bioactivities that closed to iso-PhABA and natural (+)-ABA. Some others, for instance, substituted-iso-PhABA, exhibited certain selectivity to different physiological process when compared to iso-PhABA or (+)-ABA. These analogs not only provided new candidates of ABA-like synthetic plant growth regulators (PGRs) for practical application, but also new potential selective agonist/antagonist for probing the specific function of ABA receptors.


Assuntos
Ácido Abscísico/análogos & derivados , Ácido Abscísico/síntese química , Ácido Abscísico/metabolismo , Arabidopsis/metabolismo , Germinação , Alface/metabolismo , Estrutura Molecular , Oryza/metabolismo , Reguladores de Crescimento de Planta/síntese química , Reguladores de Crescimento de Planta/metabolismo , Plântula/metabolismo , Sementes/metabolismo
11.
J Agric Food Chem ; 65(51): 11273-11279, 2017 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-29144740

RESUMO

The quality of kiwifruit became worse as a result of the abuse of plant growth regulators (PGRs). The safety of the fruits treated with PGRs also worried consumers. Therefore, the present study analyzed the structure of thidiazuron [TDZ, (1-phenyl-3-(1,2,3-thidiazol-5-yl)-urea)] (1) and its metabolites of biotransformation in kiwifruits using liquid chromatography hybrid ion trap time-of-flight mass spectrometry (LC-IT-TOF-MS). Standard compounds were also synthesized and used for structural identification of those metabolites. In addition, cytotoxicity of TDZ and its metabolites was tested through sulforhodamine B assays against normal Chinese hamster ovary (CHO) cells. Four metabolites were identified. They were 4-hydroxy-thidiazuron (2), 3-hydroxy-thidiazuron (3), thidiazuron-4-O-ß-d-glucoside (4), and thidiazuron-3-O-ß-d-glucoside (5). Values of IC50 of compounds 1, 2, and 3 to CHO cells were 18.3 ± 1.8, 37.56 ± 1.5, and 23.36 ± 1.59 µM, respectively. Compounds 4 and 5 had no effect on CHO cells.


Assuntos
Actinidia/química , Frutas/química , Compostos de Fenilureia/química , Reguladores de Crescimento de Planta/química , Tiadiazóis/química , Animais , Células CHO , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cricetinae , Cricetulus , Espectrometria de Massas , Estrutura Molecular , Compostos de Fenilureia/síntese química , Compostos de Fenilureia/metabolismo , Compostos de Fenilureia/toxicidade , Reguladores de Crescimento de Planta/síntese química , Reguladores de Crescimento de Planta/metabolismo , Reguladores de Crescimento de Planta/toxicidade , Tiadiazóis/síntese química , Tiadiazóis/metabolismo , Tiadiazóis/toxicidade
12.
Molecules ; 22(10)2017 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-29065539

RESUMO

Tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) has become a frequently deadly infection due to increasing antimicrobial resistance. This serious issue has driven efforts worldwide to discover new drugs effective against Mtb. One research area is the synthesis and evaluation of pyrazinamide derivatives as potential anti-TB drugs. In this paper we report the synthesis and biological evaluations of a series of ureidopyrazines. Compounds were synthesized by reacting alkyl/aryl isocyanates with aminopyrazine or with propyl 5-aminopyrazine-2-carboxylate. Reactions were performed in pressurized vials using a CEM Discover microwave reactor with a focused field. Purity and chemical structures of products were assessed, and the final compounds were tested in vitro for their antimycobacterial, antibacterial, and antifungal activities. Propyl 5-(3-phenylureido)pyrazine-2-carboxylate (compound 4, MICMtb = 1.56 µg/mL, 5.19 µM) and propyl 5-(3-(4-methoxyphenyl)ureido)pyrazine-2-carboxylate (compound 6, MICMtb = 6.25 µg/mL, 18.91 µM) had high antimycobacterial activity against Mtb H37Rv with no in vitro cytotoxicity on HepG2 cell line. Therefore 4 and 6 are suitable for further structural modifications that might improve their biological activity and physicochemical properties. Based on the structural similarity to 1-(2-chloropyridin-4-yl)-3-phenylurea, a known plant growth regulator, two selected compounds were evaluated for similar activity as abiotic elicitors.


Assuntos
Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Pirazinas/farmacologia , Antituberculosos/síntese química , Antituberculosos/química , Proliferação de Células/efeitos dos fármacos , Fagopyrum/química , Células Hep G2 , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Reguladores de Crescimento de Planta/síntese química , Reguladores de Crescimento de Planta/química , Reguladores de Crescimento de Planta/farmacologia , Pirazinamida/química , Pirazinamida/farmacologia , Pirazinas/síntese química , Pirazinas/química , Estresse Fisiológico/efeitos dos fármacos
13.
Org Biomol Chem ; 15(38): 8218-8231, 2017 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-28880031

RESUMO

In this paper, we synthesized and evaluated the biological activity of structural analogues of natural strigolactones in which the butenolide D-ring has been replaced with a γ-lactam. The key step to obtain the α,ß-unsaturated-γ-lactam was an RCM on suitably substituted amides. Strigolactones (SLs) are plant hormones with various developmental functions. As soil signaling chemicals, they are required for establishing beneficial mycorrhizal plant/fungus symbiosis. Beside these auxinic roles, recently SLs have been successfully investigated as antitumoral agents. Peculiar to the SL perception system is the enzymatic activity of the hormone receptor. SARs data have shown that the presence of the butenolide D-ring is crucial to retain the biological activity. The substitution of the butenolide with a lactam might shed light on the mechanism of perception. In the following, a dedicated in silico study suggested the binding modes of the synthesized compounds to the receptor of SLs in plants.


Assuntos
Lactonas/síntese química , Reguladores de Crescimento de Planta/síntese química , Germinação/efeitos dos fármacos , Lactonas/química , Modelos Moleculares , Estrutura Molecular , Micorrizas , Orobanchaceae/efeitos dos fármacos , Reguladores de Crescimento de Planta/química , Sementes/efeitos dos fármacos
14.
Z Naturforsch C J Biosci ; 72(7-8): 285-292, 2017 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-28665793

RESUMO

In higher plants, jasmonates are lipid-derived signaling molecules that control many physiological processes, including responses to abiotic stress, defenses against insects and pathogens, and development. Among jasmonates, ω-oxidized compounds form an important subfamily. The biological roles of these ω-modified derivatives are not fully understood, largely due to their limited availability. Herein, a brief (two-step), simple and efficient (>80% yield), versatile, gram-scalable, and environmentally friendly synthetic route to ω-oxidized jasmonates is described. The approach utilizes olefin cross-metathesis as the key step employing inexpensive, commercially available substrates and catalysts.


Assuntos
Alcenos/química , Ciclopentanos/química , Ciclopentanos/síntese química , Modelos Químicos , Oxilipinas/química , Oxilipinas/síntese química , Vias Biossintéticas , Catálise , Ciclopentanos/metabolismo , Hidroxilação , Estrutura Molecular , Oxilipinas/metabolismo , Reguladores de Crescimento de Planta/síntese química , Reguladores de Crescimento de Planta/química , Reguladores de Crescimento de Planta/metabolismo , Solventes/química , Temperatura Ambiente
15.
Steroids ; 125: 20-26, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28636873

RESUMO

26-Hydroxycholestan-22-one derivatives with oxygenated functions in the rings A and/or B were successfully synthesized from diosgenin. After the modifications of rings A and B, the spiroketal side chain was selectively opened through a Lewis acid mediated acetolysis to afford the cholestane derivatives. These compounds incorporate pharmacophores, which mimic the activity of natural phytohormones and show high growth promoting activity in Mexican rice cultivars using the rice lamina inclination test.


Assuntos
Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Colestanóis/química , Reguladores de Crescimento de Planta/química , Reguladores de Crescimento de Planta/farmacologia , Materiais Biomiméticos/síntese química , Relação Dose-Resposta a Droga , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Reguladores de Crescimento de Planta/síntese química
16.
Sci Rep ; 7: 43863, 2017 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-28272449

RESUMO

The phytohormone abscisic acid (ABA) plays a crucial role in mediating plant growth and development by recruiting genetically redundant ABA receptors. To overcome its oxidation inactivation, we developed a novel ABA analog named 2',3'-benzo-iso-ABA (iso-PhABA) and studied its function and structural characterization with A. thaliana ABA receptors. The (+)-iso-PhABA form showed much higher ABA-like activities than (+)-ABA including inhibitory effects on the seed germination of lettuce and A. thaliana, wheat embryo germination and rice seedling elongation. The PP2C (protein phosphatases 2C) activity assay showed that (+)-iso-PhABA acted as a potent and selective ABA receptor agonist, which is preferred to PYL10. In some cases, (-)-iso-PhABA showed moderate to high activity for the PYL protein inhibiting PP2C activity, suggesting different mechanisms of action of iso-PhABA and ABA. The complex crystal structure of iso-PhABA with PYL10 was determined and elucidated successfully, revealing that (+)-iso-PhABA was better coordinated in the same binding pocket compared to (+)-ABA. Moreover, the detailed interaction network of iso-PhABA/PYL10 was disclosed and involves hydrogen bonds and multiple hydrophobic interactions that provide a robust framework for the design of novel ABA receptor agonists/antagonists.


Assuntos
Ácido Abscísico/síntese química , Ácido Abscísico/farmacologia , Desenho de Drogas , Modelos Químicos , Ácido Abscísico/química , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/agonistas , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Cristalografia por Raios X , Germinação/efeitos dos fármacos , Alface/crescimento & desenvolvimento , Estrutura Molecular , Oryza/crescimento & desenvolvimento , Reguladores de Crescimento de Planta/síntese química , Reguladores de Crescimento de Planta/química , Reguladores de Crescimento de Planta/farmacologia , Proteína Fosfatase 2C/antagonistas & inibidores , Proteína Fosfatase 2C/metabolismo , Receptores de Superfície Celular/agonistas , Receptores de Superfície Celular/química , Receptores de Superfície Celular/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento
17.
Int J Mol Sci ; 18(3)2017 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-28282853

RESUMO

Brassinosteroids (BRs) are plant hormones that promote growth in different plant organs and tissues. The structural requirements that these compounds should possess to exhibit this biological activity have been studied. In this work, a series of known BR analogs 5-15, were synthesized starting from hyodeoxycholic acid 4, and maintaining the alkyl side chain as cholic acid or its methyl ester. The growth-promoting effects of brassinolide (1) and synthesized analogs were evaluated by using the rice lamina inclination assay at concentrations ranging from 1 × 10-8-1 × 10-6 M. Our results indicate that in this concentration range the induced bending angle of rice seedlings increases with increasing concentration of BRs. Analysis of the activities, determined at the lowest tested concentration, in terms of BR structures shows that the 2α,3α-dihydroxy-7-oxa-6-ketone moiety existing in brassinolide is required for the plant growing activity of these compounds, as it has been proposed by some structure-activity relationship studies. The effect of compound 8 on cell elongation was assessed by microscopy analysis, and the results indicate that the growth-promoting effect of analog 8 is mainly due to cell elongation of the adaxial sides, instead of an increase on cell number.


Assuntos
Brassinosteroides/síntese química , Brassinosteroides/farmacologia , Ácido Desoxicólico/química , Reguladores de Crescimento de Planta/síntese química , Reguladores de Crescimento de Planta/farmacologia , Brassinosteroides/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Reguladores de Crescimento de Planta/química , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento
18.
Nat Commun ; 8: 14318, 2017 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-28165456

RESUMO

Evolution often diversifies a peptide hormone family into multiple subfamilies, which exert distinct activities by exclusive interaction with specific receptors. Here we show that systematic swapping of pre-existing variation in a subfamily of plant CLE peptide hormones leads to a synthetic bifunctional peptide that exerts activities beyond the original subfamily by interacting with multiple receptors. This approach provides new insights into the complexity and specificity of peptide signalling.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/fisiologia , Hormônios Peptídicos/fisiologia , Reguladores de Crescimento de Planta/fisiologia , Células-Tronco/fisiologia , Sequência de Aminoácidos , Arabidopsis/citologia , Proteínas de Arabidopsis/síntese química , Biodiversidade , Evolução Molecular , Ligantes , Simulação de Acoplamento Molecular , Estrutura Molecular , Hormônios Peptídicos/síntese química , Reguladores de Crescimento de Planta/síntese química , Plantas Geneticamente Modificadas , Células-Tronco/metabolismo , Relação Estrutura-Atividade , Especificidade por Substrato/fisiologia
19.
FEBS Lett ; 591(5): 792-800, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28186640

RESUMO

Strigolactones are a new class of phytohormones synthesized from carotenoids via carlactone. The complex structure of carlactone is not easily deducible from its precursor, a cis-configured ß-carotene cleavage product, and is thus formed via a poorly understood series of reactions and molecular rearrangements, all catalyzed by only one enzyme, the carotenoid cleavage dioxygenase 8 (CCD8). Moreover, the reactions leading to carlactone are expected to form a second, yet unidentified product. In this study, we used 13 C and 18 O-labeling to shed light on the reactions catalyzed by CCD8. The characterization of the resulting carlactone by LC-MS and NMR, and the identification of the assumed, less accessible second product allowed us to formulate a minimal reaction mechanism for carlactone generation.


Assuntos
Carotenoides/química , Dioxigenases/química , Lactonas/síntese química , Reguladores de Crescimento de Planta/síntese química , Proteínas de Plantas/química , beta Caroteno/química , Biocatálise , Isótopos de Carbono , Dioxigenases/isolamento & purificação , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Isótopos de Oxigênio , Ervilhas/química , Ervilhas/enzimologia , Proteínas de Plantas/isolamento & purificação , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação
20.
Methods Mol Biol ; 1564: 9-21, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28124242

RESUMO

Synthetic derivatization of hormonally active brassinosteroids (BRs) can provide useful small molecule tools to probe BR signaling pathways, such as fluorescent analogs. However, most biologically active BRs are not suitable for direct chemical conjugation techniques because their derivatization typically requires extensive synthetic work and chemistry expertise. Here, we describe an operationally simple, two-step procedure to prepare and purify an Alexa Fluor 647-castasterone (AFCS) from commercially available materials. The reported strategy is also amenable to the introduction of various other amine-based labeling groups.


Assuntos
Brassinosteroides/síntese química , Técnicas de Química Sintética , Colestanóis/química , Oximas/química , Reguladores de Crescimento de Planta/síntese química , Carbocianinas/química , Cromatografia em Camada Delgada/métodos , Corantes Fluorescentes/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Coloração e Rotulagem/métodos
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