Estudos estruturais e computacionais de proteínas alvos de doenças negligenciadas para a descoberta de novos fármacos
Carregando...
Data
2022-05-31
Autores
Hernández Alvarez, Lilian
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
As doenças tropicais negligenciadas (NTDs) são infecções prevalentes em áreas remotas e rurais de países pobres da África Subsaariana, Ásia e América, que têm sido historicamente desatendidas e representam o mercado de menor prioridade das grandes indústrias farmacêuticas. As NTDs causadas por parasitas protozoários apresentam altos índices de morbilidade e mortalidade, e os tratamentos disponíveis são tóxicos e ineficientes. Neste estudo, técnicas experimentais e computacionais foram utilizadas para contribuir ao conhecimento das bases moleculares de diversos alvos proteicos dessas doenças com vistas ao desenvolvimento de futuros fármacos. Estratégias computacionais foram empregadas com o objetivo de identificar novos inibidores competitivos da cruzaína, a maior cisteíno protease do Trypanosoma cruzi. A avaliação experimental nos permitiu descobrir um novo inibidor competitivo desta protease com um IC50 inferior a 15 μM. Além disso, foi determinada a estruturas de raios-X do complexo cruzaína-gallinamida A e métodos computacionais nos permitiram identificar os determinantes atômico-estruturais subjacentes na inibição seletiva desta série de compostos. Por outro lado, as bases moleculares da modulação alostérica exercida sobre fator de iniciação de tradução eucariótica 4E 1 (LmIF4E-1) em Leishmania major pela proteína 4E-IP1 (Lm4E-IP1) foram desvendadas utilizando métodos in silico. Nesse sentido, foram determinadas as diferenças nos movimentos internos das formas apo e complexadas com Lm4E-IP1 e com cap da LmIF4E-1. Este estudo permitiu detalhar as perturbações dinâmicas ocorridas no sítio principal de ligação da LmIF4E-1 desencadeadas pela união com Lm4E-IP1. Esta analise contribuiu à compreensão do processo da expressão gênica nos tripanossomatídeos e revelou informações cruciais da regulação alostérica nas eIF4Es. Por fim, foi realizada a modelagem computacional do homodímero da esterol 14alfa-desmetilase (AcCYP51) de Acanthamoeba castellani inserido numa bicamada lipídica. Nosso modelo revelou que o dímero permanece estável, interagindo com a bicamada ao longo do tempo de simulação. Esses resultados também nos forneceram informações sobre a potência superior do isavuconazol contra esse parasita comparados com outros do mesmo gênero.
Neglected tropical diseases (NTDs) are a group of infections that are prevalent in remote and rural areas of low-income countries in Sub-Saharan Africa, Asia, and the Americas. These diseases do not receive enough attention, representing the lowest priority markets for the big pharmaceutical manufacturers. NTDs caused by protozoan parasites are responsible for significant morbidity and mortality and current drug treatments are toxic and prolonged. Here, experimental and computational approaches were employed to contribute to the knowledge of the molecular bases of several targets and the development of future drugs against these diseases. A computational strategy was employed to predict novel competitive inhibitors against the papain-like cysteine protease cruzain. The experimental evaluation of the predicted compounds allowed us to identify a novel competitive inhibitor of this protease with an IC50 under 15 μM. In addition, the X-ray structures of the cruzain complexes with gallinamide A and analogs were also determined, and two series of synthetic gallinamide A analogs (23 compounds) were evaluated against cruzain and intracellular Trypanosoma cruzi amastigotes. The employed computational techniques allowed us to identify the hot spots and structural determinates underlying the selective inhibition of this compound series. Moreover, in silico strategy was developed to elucidate the molecular bases of the previously-reported allosteric modulation in Leishmania major exerted by 4E-IP1 (Lm4E-IP1) on eukaryotic translation initiation factor 4E 1 (LmIF4E-1). Here, the differences in internal motions of LmIF4E-1 apo form, cap-bound, and Lm4E-IP1-bound systems were described. This study thoroughly describes the dynamical perturbations of LmIF4E-1 cap-binding site triggered by Lm4E IP1, providing an understanding of trypanosomatids’ gene expression and gaining insight into the allostery of eIF4Es. Finally, the computational modeling of full-length sterol 14alpha-demethylase (AcCYP51) homodimer of Acanthamoeba castellani inserted in a lipid bilayer was performed. Our model revealed that AcCYP51 dimer interacts with the membrane lipids and remains stable within the bilayer along the simulation time. These results also provided us the insights into the superior potency of isavuconazole against this parasite.
Neglected tropical diseases (NTDs) are a group of infections that are prevalent in remote and rural areas of low-income countries in Sub-Saharan Africa, Asia, and the Americas. These diseases do not receive enough attention, representing the lowest priority markets for the big pharmaceutical manufacturers. NTDs caused by protozoan parasites are responsible for significant morbidity and mortality and current drug treatments are toxic and prolonged. Here, experimental and computational approaches were employed to contribute to the knowledge of the molecular bases of several targets and the development of future drugs against these diseases. A computational strategy was employed to predict novel competitive inhibitors against the papain-like cysteine protease cruzain. The experimental evaluation of the predicted compounds allowed us to identify a novel competitive inhibitor of this protease with an IC50 under 15 μM. In addition, the X-ray structures of the cruzain complexes with gallinamide A and analogs were also determined, and two series of synthetic gallinamide A analogs (23 compounds) were evaluated against cruzain and intracellular Trypanosoma cruzi amastigotes. The employed computational techniques allowed us to identify the hot spots and structural determinates underlying the selective inhibition of this compound series. Moreover, in silico strategy was developed to elucidate the molecular bases of the previously-reported allosteric modulation in Leishmania major exerted by 4E-IP1 (Lm4E-IP1) on eukaryotic translation initiation factor 4E 1 (LmIF4E-1). Here, the differences in internal motions of LmIF4E-1 apo form, cap-bound, and Lm4E-IP1-bound systems were described. This study thoroughly describes the dynamical perturbations of LmIF4E-1 cap-binding site triggered by Lm4E IP1, providing an understanding of trypanosomatids’ gene expression and gaining insight into the allostery of eIF4Es. Finally, the computational modeling of full-length sterol 14alpha-demethylase (AcCYP51) homodimer of Acanthamoeba castellani inserted in a lipid bilayer was performed. Our model revealed that AcCYP51 dimer interacts with the membrane lipids and remains stable within the bilayer along the simulation time. These results also provided us the insights into the superior potency of isavuconazole against this parasite.
Descrição
Palavras-chave
Trypanosoma cruzi, Leishmania, Acanthamoeba castellanii, LmIF4E-1, Cruzaína, Dímero AcCYP51, Alosteria, Dinâmica molecular, Triagem virtual, Energia livre de ligação, Ensaio enzimático, Modo de ligação, Cristalografia de raios X, NTDs, Parasite, Chagas, Cruzain, AcCYP51 dimer, Allostery, Molecular dynamics simulation, Virtual screening, Free energy, Inhibition assays, Binding mode, Community analysis, X-ray crystallography