RESUMO
Melatonin receptors MT1 and MT2 are G protein-coupled receptors that mediate the effects of melatonin, a hormone involved in circadian rhythms and other physiological functions. Understanding the molecular interactions between these receptors and their ligands is crucial for developing novel therapeutic agents. In this study, we used molecular docking, molecular dynamics simulations, and quantum mechanics calculation to investigate the binding modes and affinities of three ligands: melatonin (MLT), ramelteon (RMT), and 2-phenylmelatonin (2-PMT) with both receptors. Based on the results, we identified key amino acids that contributed to the receptor-ligand interactions, such as Gln181/194, Phe179/192, and Asn162/175, which are conserved in both receptors. Additionally, we described new meaningful interactions with Gly108/Gly121, Val111/Val124, and Val191/Val204. Our results provide insights into receptor-ligand recognition's structural and energetic determinants and suggest potential strategies for designing more optimized molecules. This study enhances our understanding of receptor-ligand interactions and offers implications for future drug development.
Assuntos
Melatonina , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ligação Proteica , Receptor MT1 de Melatonina , Receptor MT2 de Melatonina , Melatonina/metabolismo , Melatonina/química , Receptor MT2 de Melatonina/metabolismo , Receptor MT2 de Melatonina/química , Receptor MT1 de Melatonina/metabolismo , Receptor MT1 de Melatonina/química , Humanos , Ligantes , Teoria Quântica , Sítios de Ligação , Indenos/química , Indenos/metabolismoRESUMO
The phytohormone jasmonoyl-isoleucine (JA-Ile) regulates fundamental plant processes as developmental and defense responses. JA-Ile mediates the interaction between the F-box protein COI1 (part of the SCFCOI1 E3 ubiquitin ligase) and a JAZ repressor leading to early jasmonate responses. The Arabidopsis JAZ1 protein contains the canonical LPIARR degron sequence, which is responsible for the stabilization of the AtCOI1-JA-Ile-AtJAZ1 complex. In strawberry (Fragaria × ananassa) JAZ family was described at the transcriptional level during fruit development but the information about the interaction mode of this complex is still scarce at the molecular level. To gain insight into the strawberry JA-Ile receptor complex, we evaluated the interaction at the structural level, and protein models were built and analyzed for FaCOI1 and FaJAZ1, FaJAZ8.1, and FaJAZ10. The interaction between FaCOI1 and FaJAZ1, FaJAZ8.1 and FaJAZ10 were explored using several ligands, through molecular docking and molecular dynamics (MD) simulations, finding the strongest interaction with (+)-7-iso-JA-Ile than other ligands. Additionally, we tested interactions between FaCOI1 and FaJAZs by yeast two-hybrid assays in the presence of coronatine (COR, a JA-Ile mimic). We detected strong COR-dependent interactions between FaCOI1 and FaJAZ1. Interestingly, FaJAZ1 contains a new non-canonical (IPMQRK) functional degron sequence, in which Arg and Lys are the key residues for maintaining the interaction of the FaCOI1-COR-FaJAZ1 complex as we observed in mutated versions of the FaJAZ1 degron. Phylogenetic analysis showed that the IPMQRK degron is only present in orthologs belonging to the Rosoideae but not in other Rosaceae subfamilies. Together, this study uncovers a new degron sequence in plants, which could be required to make an alternative and functional JA-Ile perception complex in strawberry.
Assuntos
Fragaria/química , Proteínas de Plantas/química , Aminoácidos/metabolismo , Fragaria/genética , Indenos/metabolismo , Filogenia , Proteínas de Plantas/genética , Ligação Proteica , Conformação ProteicaRESUMO
Pseudomonas syringae is a phytopathogenic bacterium that causes lesions in leaves during the colonisation process. The damage is associated with production of many virulence factors, such as biofilm and phytotoxins. The essential oils of Thymus vulgaris (thyme) and Origanum vulgare (oregano) have been demonstrated to inhibit P. syringae. The aim of this study was to investigate the effects of T. vulgaris and O. vulgare essential oils on production of virulence factors of phytopathogenic P. syringae strains, including anti-biofilm and anti-toxins activities. The broth microdilution method was used for determination of MIC and biofilm inhibition assays. Coronatine, syringomycin and tabtoxin were pheno- and genotypically evaluated. Both oils showed good inhibitory activity against P. syringae, with MIC values from 1.43 to 11.5 mg·ml-1 for thyme and 5.8 to 11.6 mg·ml-1 for oregano. Biofilm formation, production of coronatine, syringomycin and tabtoxin were inhibited by thyme and oregano essential oil in most strains. The results presented here are promising, demonstrating the bactericidal activity and reduction of virulence factor production after treatment with thyme and oregano oil, providing insight into how they exert their antibacterial activity. These natural products could be considered in the future for the control of diseases caused by P. syringae.
Assuntos
Óleos Voláteis/química , Óleos Voláteis/farmacologia , Origanum/química , Extratos Vegetais/farmacologia , Pseudomonas syringae/efeitos dos fármacos , Pseudomonas syringae/metabolismo , Thymus (Planta)/química , Fatores de Virulência/metabolismo , Aminoácidos/metabolismo , Proteínas de Bactérias/metabolismo , Dipeptídeos/metabolismo , Indenos/metabolismo , Testes de Sensibilidade MicrobianaRESUMO
Ketonic indeno[1,2-b]indole-9,10-dione derivatives, initially designed as human casein kinase II (CK2) inhibitors, were recently shown to be converted into efficient inhibitors of drug efflux by the breast cancer resistance protein ABCG2 upon suited substitutions including a N (5)-phenethyl on C-ring and hydrophobic groups on D-ring. A series of ten phenolic and seven p-quinonic derivatives were synthesized and screened for inhibition of both CK2 and ABCG2 activities. The best phenolic inhibitors were about threefold more potent against ABCG2 than the corresponding ketonic derivatives, and showed low cytotoxicity. They were selective for ABCG2 over both P-glycoprotein and MRP1 (multidrug resistance protein 1), whereas the ketonic derivatives also interacted with MRP1, and they additionally displayed a lower interaction with CK2. Quite interestingly, they strongly stimulated ABCG2 ATPase activity, in contrast to ketonic derivatives, suggesting distinct binding sites. In contrast, the p-quinonic indenoindoles were cytotoxic and poor ABCG2 inhibitors, whereas a partial inhibition recovery could be reached upon hydrophobic substitutions on D-ring, similarly to the ketonic derivatives.
Assuntos
Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Antineoplásicos/farmacologia , Desenho de Fármacos , Indenos/farmacologia , Indóis/farmacologia , Proteínas de Neoplasias/antagonistas & inibidores , Fenóis/farmacologia , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/química , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Sítios de Ligação , Caseína Quinase II/antagonistas & inibidores , Caseína Quinase II/química , Caseína Quinase II/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células HEK293 , Humanos , Interações Hidrofóbicas e Hidrofílicas , Indenos/síntese química , Indenos/metabolismo , Indóis/síntese química , Indóis/metabolismo , Camundongos , Mitoxantrona/metabolismo , Modelos Moleculares , Estrutura Molecular , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Proteínas Associadas à Resistência a Múltiplos Medicamentos/química , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Células NIH 3T3 , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Fenóis/síntese química , Fenóis/metabolismo , Ligação Proteica , Relação Estrutura-Atividade , TransfecçãoRESUMO
Brazilein, a natural small molecule, shows a variety of pharmacological activities, especially on nervous system and immune system. As a potential multifunctional drug, we studied the distribution and the transport behavior and metabolic behavior of brazilein in vivo and in vitro. Brazilein was found to be able to distribute in the mouse brain and transport into neural cells. A metabolite was found in the brain and in the cells. Positive and negative mode-MS/MS and Q-TOF were used to identify the metabolite. MS/MS fragmentation mechanisms showed the methylation occurred at the 10-hydroxyl of brazilein (10-O-methylbrazilein). Further, catechol-O- methyltransferase (COMT) was confirmed as a crucial enzyme correlated with the methylated metabolite generation by molecular docking and pharmacological experiment.
Assuntos
Benzopiranos/metabolismo , Indenos/metabolismo , Neurônios/metabolismo , Animais , Benzopiranos/administração & dosagem , Benzopiranos/química , Benzopiranos/farmacologia , Transporte Biológico/efeitos dos fármacos , Encéfalo/metabolismo , Catecol O-Metiltransferase/química , Catecol O-Metiltransferase/metabolismo , Morte Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Complexo IV da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Indenos/administração & dosagem , Indenos/química , Indenos/farmacologia , Masculino , Metilação/efeitos dos fármacos , Camundongos Endogâmicos ICR , Neurônios/efeitos dos fármacos , Células PC12 , Ratos , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Temperatura , Raios UltravioletaRESUMO
To optimize the medium for high zofimarin production, sucrose maltose, glucose, tryptone and peptone were used in an orthogonal array design experiment, where the highest value of zofimarin produced was 25.6 µg/mL. This value was about 3 times higher than that obtained with Czapek yeast extract (CzYE) culture medium. A study with Plackett-Burman design showed that sucrose, maltose, glucose and NaNO3 were significant factors in zofimarin production. Further studies using central composite design (CCD) showed the significance of glucose and the interactions of these critical components affecting zofimarin production. Multiple regression analysis of the data yielded a poor fit as shown by the mismatch of the model with these variable factors. When a polynomial equation was applied, the maximum zofimarin production was predicted to be 201.9 µg/mL. Experimental verification yielded a much lower amount of zofimarin, at around 70 µg/mL. Reconsideration of the CCD data and repetition of some runs with high zofimarin production resulted in reproducible zofimarin yield at 79.7 µg/mL. Even though the amount was lower than the predicted value, the medium optimization study was considered to be quite successful as the yield increased to around 8 times that obtained with the original CzYE culture medium.
Assuntos
Antifúngicos/metabolismo , Meios de Cultura/química , Endófitos/metabolismo , Xylariales/metabolismo , Indenos/metabolismoRESUMO
To optimize the medium for high zofimarin production, sucrose maltose, glucose, tryptone and peptone were used in an orthogonal array design experiment, where the highest value of zofimarin produced was 25.6 µg/mL. This value was about 3 times higher than that obtained with Czapek yeast extract (CzYE) culture medium. A study with Plackett-Burman design showed that sucrose, maltose, glucose and NaNO3 were significant factors in zofimarin production. Further studies using central composite design (CCD) showed the significance of glucose and the interactions of these critical components affecting zofimarin production. Multiple regression analysis of the data yielded a poor fit as shown by the mismatch of the model with these variable factors. When a polynomial equation was applied, the maximum zofimarin production was predicted to be 201.9 µg/mL. Experimental verification yielded a much lower amount of zofimarin, at around 70 µg/mL. Reconsideration of the CCD data and repetition of some runs with high zofimarin production resulted in reproducible zofimarin yield at 79.7 µ/mL. Even though the amount was lower than the predicted value, the medium optimization study was considered to be quite successful as the yield increased to around 8 times that obtained with the original CzYE culture medium.
Assuntos
Antifúngicos/metabolismo , Meios de Cultura/química , Endófitos/metabolismo , Xylariales/metabolismo , Indenos/metabolismoRESUMO
To optimize the medium for high zofimarin production, sucrose maltose, glucose, tryptone and peptone were used in an orthogonal array design experiment, where the highest value of zofimarin produced was 25.6 µg/mL. This value was about 3 times higher than that obtained with Czapek yeast extract (CzYE) culture medium. A study with Plackett-Burman design showed that sucrose, maltose, glucose and NaNO3 were significant factors in zofimarin production. Further studies using central composite design (CCD) showed the significance of glucose and the interactions of these critical components affecting zofimarin production. Multiple regression analysis of the data yielded a poor fit as shown by the mismatch of the model with these variable factors. When a polynomial equation was applied, the maximum zofimarin production was predicted to be 201.9 µg/mL. Experimental verification yielded a much lower amount of zofimarin, at around 70 µg/mL. Reconsideration of the CCD data and repetition of some runs with high zofimarin production resulted in reproducible zofimarin yield at 79.7 µ/mL. Even though the amount was lower than the predicted value, the medium optimization study was considered to be quite successful as the yield increased to around 8 times that obtained with the original CzYE culture medium.(AU)
Assuntos
Antifúngicos/metabolismo , Meios de Cultura/química , Endófitos/metabolismo , Xylariales/metabolismo , Indenos/metabolismoRESUMO
The phyllosphere, i.e., the aerial parts of the plant, provides one of the most important niches for microbial colonization. This niche supports the survival and, often, proliferation of microbes such as fungi and bacteria with diverse lifestyles including epiphytes, saprophytes, and pathogens. Although most microbes may complete the life cycle on the leaf surface, pathogens must enter the leaf and multiply aggressively in the leaf interior. Natural surface openings, such as stomata, are important entry sites for bacteria. Stomata are known for their vital role in water transpiration and gas exchange between the plant and the environment that is essential for plant growth. Recent studies have shown that stomata can also play an active role in limiting bacterial invasion of both human and plant pathogenic bacteria as part of the plant innate immune system. As counter-defense, plant pathogens such as Pseudomonas syringae pv tomato (Pst) DC3000 use the virulence factor coronatine to suppress stomate-based defense. A novel and crucial early battleground in host-pathogen interaction in the phyllosphere has been discovered with broad implications in the study of bacterial pathogenesis, host immunity, and molecular ecology of bacterial diseases.
Assuntos
Aminoácidos/metabolismo , Indenos/metabolismo , Solanum lycopersicum/fisiologia , Folhas de Planta/fisiologia , Estômatos de Plantas/fisiologia , Pseudomonas syringae/patogenicidade , Fatores de Virulência/fisiologia , Aminoácidos/genética , Solanum lycopersicum/genética , Solanum lycopersicum/microbiologia , Folhas de Planta/microbiologia , Estômatos de Plantas/microbiologia , Pseudomonas syringae/genética , Fatores de Virulência/genéticaRESUMO
The phyllosphere, i.e., the aerial parts of the plant, provides one of the most important niches for microbial colonization. This niche supports the survival and, often, proliferation of microbes such as fungi and bacteria with diverse lifestyles including epiphytes, saprophytes, and pathogens. Although most microbes may complete the life cycle on the leaf surface, pathogens must enter the leaf and multiply aggressively in the leaf interior. Natural surface openings, such as stomata, are important entry sites for bacteria. Stomata are known for their vital role in water transpiration and gas exchange between the plant and the environment that is essential for plant growth. Recent studies have shown that stomata can also play an active role in limiting bacterial invasion of both human and plant pathogenic bacteria as part of the plant innate immune system. As counter-defense, plant pathogens such as Pseudomonas syringae pv tomato (Pst) DC3000 use the virulence factor coronatine to suppress stomate-based defense. A novel and crucial early battleground in host-pathogen interaction in the phyllosphere has been discovered with broad implications in the study of bacterial pathogenesis, host immunity, and molecular ecology of bacterial diseases.