Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 84
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Methods ; 219: 82-94, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37778659

RESUMO

Artificial intelligence (AI), particularly deep learning as a subcategory of AI, provides opportunities to accelerate and improve the process of discovering and developing new drugs. The use of AI in drug discovery is still in its early stages, but it has the potential to revolutionize the way new drugs are discovered and developed. As AI technology continues to evolve, it is likely that AI will play an even greater role in the future of drug discovery. AI is used to identify new drug targets, design new molecules, and predict the efficacy and safety of potential drugs. The inclusion of AI in drug discovery can screen millions of compounds in a matter of hours, identifying potential drug candidates that would have taken years to find using traditional methods. AI is highly utilized in the pharmaceutical industry by optimizing processes, reducing waste, and ensuring quality control. This review covers much-needed topics, including the different types of machine-learning techniques, their applications in drug discovery, and the challenges and limitations of using machine learning in this field. The state-of-the-art of AI-assisted pharmaceutical discovery is described, covering applications in structure and ligand-based virtual screening, de novo drug creation, prediction of physicochemical and pharmacokinetic properties, drug repurposing, and related topics. Finally, many obstacles and limits of present approaches are outlined, with an eye on potential future avenues for AI-assisted drug discovery and design.


Assuntos
Inteligência Artificial , Aprendizado de Máquina , Desenho de Fármacos , Descoberta de Drogas/métodos , Preparações Farmacêuticas
2.
Environ Res ; 257: 119331, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38851371

RESUMO

Toxicological stress in aquatic organisms is caused by the discharge of hundreds of toxic pollutants and contaminants among which the current study concentrates on the toxic effect of non-steroidal anti-inflammatory drug ibuprofen (IBF) and the trace element selenium (Se). In this study, IBF and Se toxicity on freshwater mussel Lamellidens marginalis was studied for 14 days, and in silico predictions for their degradation were made using Molecular modelling and Quantum Mechanical approaches. The degrading propensity of cytochrome c oxidase proteins from Trametes verticillatus and Thauera selenatis (Turkey tail fungi and Gram-negative bacteria) is examined into atom level. The results of molecular modelling study indicate that ionic interactions occur in the T. selenatis-HEME bound complex by Se interacting directly with HEME, and in the T. versicolor-HEME bound complex by IBF bound to a nearby region of HEME. Experimental and theoretical findings suggest that, the toxicological effects of Se and IBF pollution can be reduced by bioremediation with special emphasis on T. versicolor, and T. selenatis, which can effectively interact with Se and IBF present in the environment and degrade them. Besides, this is the first time in freshwater mussel L. marginalis that ibuprofen and selenium toxicity have been studied utilizing both experimental and computational methodologies for their bioremediation study.

3.
J Cell Mol Med ; 27(24): 3966-3973, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37772815

RESUMO

LncRNA Survival Associated Mitochondrial Melanoma Specific Oncogenic Non-coding RNA (SAMMSON) is located on human chromosome 3p13, and its expression is upregulated in several tumours, including melanoma, breast cancer, glioblastoma and liver cancer and has an oncogenic role in malignancy disorders. It has been reported that SAMMSON impacts metabolic regulation, cell proliferation, apoptosis, EMT, drug resistance, invasion and migration. Also, SAMMSON is involved in regulating several pathways such as Wnt, MAPK, PI3K, Akt, ERK and p53. SAMMSON is considered a potential diagnostic and prognostic biomarker in several types of cancer and a suitable therapeutic target. In addition, the highly expressed SAMMSON is closely associated with clinicopathological features of various cancers. SAMMSON has a significant role in regulating epigenetic processes by regulating histone protein or the status of DNA methylation. Herein for the first time, we comprehensively summarized the currently available SAMMSON, molecular regulatory pathways, and clinical significance. We believe that clarifying all the molecular aspects of this lncRNA can be a good guide for cancer studies in the future.


Assuntos
Melanoma , RNA Longo não Codificante , Humanos , Melanoma/genética , Melanoma/patologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Transformação Celular Neoplásica/genética , Carcinogênese/genética , Histonas/metabolismo , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral
4.
Mol Biol Rep ; 50(11): 9367-9378, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37819498

RESUMO

OBJECTIVE: To observe the effects of acupuncture and moxibustion therapy on pain relief in sciatica rats and to explore the mechanism of its anti-inflammatory effect. METHODS: SPF grade 4-6-week-old Kunming rats were randomly divided into 5 groups including a blank group, sham-operated group, model group, acupuncture, and moxibustion (AnM) group, and positive group. A total of 10 rats were included in each group. The model group, the AnM group, and the positive group were prepared by ligating the left sciatic nerve. AnM group was used for acupuncture and moxibustion therapy intervention, and the positive group was rendered to quick-acting sciatica pills once a day for 7 days (3 courses of treatment). The blank group, sham-operated group, and model group were not treated. The changes in thermal and mechanical pain thresholds were observed before and after the operation, and the morphological changes of the dorsal horn of the spinal cord in the lumbosacral region of the rats in each group were observed by HE staining after the courses of treatment finished. The contents of IL-1ß, IL-6, IL-18, and TNF-α were measured by ELISA and the expressions of NOX1, NOX2, NOX4, and NLRP3 genes were detected by RT-qPCR while the protein expressions of NOX1, NOX2, NOX4 and NLRP3 were analyzed by Western blotting. RESULTS: The AnM and positive group showed a significant increase in thermal and mechanical pain thresholds after treatment, while there was no significant change in the model group. As compared to the control group, the contents of IL- 1ß, IL-6, IL-18, and TNF-α, as well as the relative expressions of NOX1, NOX2, NOX4, and NLRP3 genes were significantly increased in the model group (P < 0.05 or P < 0.01). As compared to the model group, the contents of IL-1ß, IL-6, IL-18, and TNF-α, as well as the relative expressions of NOX1, NOX2, NOX4, and NLRP3 genes significantly decreased in the AnM and positive groups (P < 0.05 or P < 0.01). The pathological changes of inflammatory infiltration of tissue cells in the dorsal horn of the lumbosacral spinal cord were slowed in the AnM group. CONCLUSION: Acupuncture and moxibustion therapy have a positive effect on pain relief and anti-inflammatory effects in CCI sciatica rats, which may point to the regulation of NOX1, NOX2, NOX4, and NLRP3 expressions, and inhibition of ROS.


Assuntos
Terapia por Acupuntura , Moxibustão , Ciática , Ratos , Animais , Interleucina-18 , Proteína 3 que Contém Domínio de Pirina da Família NLR , Espécies Reativas de Oxigênio , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6
5.
Fish Shellfish Immunol ; 121: 183-196, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34971736

RESUMO

Analyzing the health benefits of any two immunostimulants (synbiotics) in combined form and information on their interactions gain more visibility in the usage of synbiotics in aquafarms. With this intention, the current work explores the immunostimulant effect and structural interaction of synbiotic (ß-1, 3 glucan binding protein from marine crab, Portunus pelagicus (Ppß-GBP) and Bacillus licheniformis) on Oreochromis mossambicus. The experimental diet was prepared with Ppß-GBP and B. licheniformis, and nourished to the fingerlings of O. mossambicus for 30 days. After the experimental trial, a higher growth rate and immune reactions (lysozyme, protease, myeloperoxidase and alkaline phosphatase activity) were noticed in the fish nourished with synbiotic (B. licheniformis and Ppß-GBP) enriched diet. Moreover, the synbiotic enriched diet elevated the antioxidant responses like glutathione peroxidase (GSH-Px) and catalase (CAT) activity in the experimental diet-nurtured fish. At the end of the feed trial, synbiotic diet nourished fish shows an increased survival rate during Aeromonas hydrophila infection, reflecting the disease resistance potential of experimental fish. Also, the interaction between Ppß-GBP and Bacillus licheniformis was analyzed through computational approaches. The results evidenced that, Ppß-GBP interacts with the B. licheniformis through sugar-based ligand, ß-glucan through a hydrogen bond with a good docking score. Thus, the synbiotic diet would be an effective immunostimulant to strengthen the fish immune system for better productivity.


Assuntos
Adjuvantes Imunológicos , Bacillus licheniformis , Proteínas de Transporte/imunologia , Doenças dos Peixes , Lectinas/imunologia , Tilápia , Aeromonas hydrophila , Ração Animal/análise , Animais , Antioxidantes/metabolismo , Bacillus licheniformis/imunologia , Dieta/veterinária , Resistência à Doença , Simbióticos
6.
Mol Divers ; 26(3): 1893-1913, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34686947

RESUMO

The global spread of COVID-19 has raised the importance of pharmaceutical drug development as intractable and hot research. Developing new drug molecules to overcome any disease is a costly and lengthy process, but the process continues uninterrupted. The critical point to consider the drug design is to use the available data resources and to find new and novel leads. Once the drug target is identified, several interdisciplinary areas work together with artificial intelligence (AI) and machine learning (ML) methods to get enriched drugs. These AI and ML methods are applied in every step of the computer-aided drug design, and integrating these AI and ML methods results in a high success rate of hit compounds. In addition, this AI and ML integration with high-dimension data and its powerful capacity have taken a step forward. Clinical trials output prediction through the AI/ML integrated models could further decrease the clinical trials cost by also improving the success rate. Through this review, we discuss the backend of AI and ML methods in supporting the computer-aided drug design, along with its challenge and opportunity for the pharmaceutical industry. From the available information or data, the AI and ML based prediction for the high throughput virtual screening. After this integration of AI and ML, the success rate of hit identification has gained a momentum with huge success by providing novel drugs.


Assuntos
Inteligência Artificial , Tratamento Farmacológico da COVID-19 , Desenho de Fármacos , Indústria Farmacêutica , Humanos , Aprendizado de Máquina
7.
Int J Mol Sci ; 22(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209188

RESUMO

Coronavirus disease (COVID)-19 is the leading global health threat to date caused by a severe acute respiratory syndrome coronavirus (SARS-CoV-2). Recent clinical trials reported that the use of Bruton's tyrosine kinase (BTK) inhibitors to treat COVID-19 patients could reduce dyspnea and hypoxia, thromboinflammation, hypercoagulability and improve oxygenation. However, the mechanism of action remains unclear. Thus, this study employs structure-based virtual screening (SBVS) to repurpose BTK inhibitors acalabrutinib, dasatinib, evobrutinib, fostamatinib, ibrutinib, inositol 1,3,4,5-tetrakisphosphate, spebrutinib, XL418 and zanubrutinib against SARS-CoV-2. Molecular docking is conducted with BTK inhibitors against structural and nonstructural proteins of SARS-CoV-2 and host targets (ACE2, TMPRSS2 and BTK). Molecular mechanics-generalized Born surface area (MM/GBSA) calculations and molecular dynamics (MD) simulations are then carried out on the selected complexes with high binding energy. Ibrutinib and zanubrutinib are found to be the most potent of the drugs screened based on the results of computational studies. Results further show that ibrutinib and zanubrutinib could exploit different mechanisms at the viral entry and replication stage and could be repurposed as potential inhibitors of SARS-CoV-2 pathogenesis.


Assuntos
Adenina/análogos & derivados , Reposicionamento de Medicamentos , Simulação de Dinâmica Molecular , Piperidinas/química , Inibidores de Proteínas Quinases/química , Pirazóis/química , Pirimidinas/química , Adenina/química , Adenina/metabolismo , Adenina/uso terapêutico , Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Tirosina Quinase da Agamaglobulinemia/metabolismo , Enzima de Conversão de Angiotensina 2/antagonistas & inibidores , Enzima de Conversão de Angiotensina 2/metabolismo , Sítios de Ligação , COVID-19/patologia , COVID-19/virologia , Humanos , Simulação de Acoplamento Molecular , Piperidinas/metabolismo , Piperidinas/uso terapêutico , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Pirazóis/metabolismo , Pirazóis/uso terapêutico , Pirimidinas/metabolismo , Pirimidinas/uso terapêutico , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/metabolismo , Serina Endopeptidases/química , Serina Endopeptidases/metabolismo , Termodinâmica , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/metabolismo , Tratamento Farmacológico da COVID-19
8.
Int J Mol Sci ; 22(17)2021 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-34502280

RESUMO

Estrogen receptor alpha (ERα) is a ligand-dependent transcriptional factor in the nuclear receptor superfamily. Many structures of ERα bound with agonists and antagonists have been determined. However, the dynamic binding patterns of agonists and antagonists in the binding site of ERα remains unclear. Therefore, we performed molecular docking, molecular dynamics (MD) simulations, and quantum mechanical calculations to elucidate agonist and antagonist dynamic binding patterns in ERα. 17ß-estradiol (E2) and 4-hydroxytamoxifen (OHT) were docked in the ligand binding pockets of the agonist and antagonist bound ERα. The best complex conformations from molecular docking were subjected to 100 nanosecond MD simulations. Hierarchical clustering was conducted to group the structures in the trajectory from MD simulations. The representative structure from each cluster was selected to calculate the binding interaction energy value for elucidation of the dynamic binding patterns of agonists and antagonists in the binding site of ERα. The binding interaction energy analysis revealed that OHT binds ERα more tightly in the antagonist conformer, while E2 prefers the agonist conformer. The results may help identify ERα antagonists as drug candidates and facilitate risk assessment of chemicals through ER-mediated responses.


Assuntos
Estradiol/metabolismo , Receptor alfa de Estrogênio/agonistas , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/metabolismo , Tamoxifeno/análogos & derivados , Estradiol/química , Receptor alfa de Estrogênio/química , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Teoria Quântica , Tamoxifeno/química , Tamoxifeno/metabolismo
9.
Molecules ; 25(12)2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32575485

RESUMO

Selectins belong to a group of adhesion molecules that fulfill an essential role in immune and inflammatory responses and tissue healing. Selectins are glycoproteins that decode the information carried by glycan structures, and non-covalent interactions of selectins with these glycan structures mediate biological processes. The sialylated and fucosylated tetrasaccharide sLex is an essential glycan recognized by selectins. Several glycosyltransferases are responsible for the biosynthesis of the sLex tetrasaccharide. Selectins are involved in a sequence of interactions of circulated leukocytes with endothelial cells in the blood called the adhesion cascade. Recently, it has become evident that cancer cells utilize a similar adhesion cascade to promote metastases. However, like Dr. Jekyll and Mr. Hyde's two faces, selectins also contribute to tissue destruction during some infections and inflammatory diseases. The most prominent function of selectins is associated with the initial stage of the leukocyte adhesion cascade, in which selectin binding enables tethering and rolling. The first adhesive event occurs through specific non-covalent interactions between selectins and their ligands, with glycans functioning as an interface between leukocytes or cancer cells and the endothelium. Targeting these interactions remains a principal strategy aimed at developing new therapies for the treatment of immune and inflammatory disorders and cancer. In this review, we will survey the significant contributions to and the current status of the understanding of the structure of selectins and the role of selectins in various biological processes. The potential of selectins and their ligands as therapeutic targets in chronic and acute inflammatory diseases and cancer will also be discussed. We will emphasize the structural characteristic of selectins and the catalytic mechanisms of glycosyltransferases involved in the biosynthesis of glycan recognition determinants. Furthermore, recent achievements in the synthesis of selectin inhibitors will be reviewed with a focus on the various strategies used for the development of glycosyltransferase inhibitors, including substrate analog inhibitors and transition state analog inhibitors, which are based on knowledge of the catalytic mechanism.


Assuntos
Adesão Celular , Migração e Rolagem de Leucócitos , Leucócitos/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Selectinas/metabolismo , Animais , Humanos , Inflamação/metabolismo , Inflamação/patologia , Leucócitos/patologia , Neoplasias/patologia
10.
J Mol Recognit ; 29(5): 186-98, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26686319

RESUMO

In invertebrates, the prophenoloxidase (proPO) pathway is involved in the phenol-like antioxidant production against invading pathogens. Overproduction of melanin and phenolic substances leads to the disruption of hemocytes (own host cells); therefore, there is a prerequisite to regulate the antioxidant production, which is performed by the proteases and proPO-associated cell adhesion protein peroxinectin (PX). PX is a macromolecular structure consisting of protein involved in the proPO pathway, which is a potential target in the regulatory mechanism in crustaceans. In the proPO cascade, pattern recognition proteins initiate the proPO cascade by the consequent reaction, and PX is involved in the key step in the regulatory mechanism of phenoloxidase enzyme synthesis. In the present study, Indian white shrimp Fenneropenaeus indicus PX (Fein-PX) gene sequence was used. Upregulation of Fein-PX was determined using immunostimulants ß-glucan (agonists) and examined its expression by quantitative RT-PCR. To find the downregulation or negative regulation of Fein-PX, inhibitors were screened, and its 3D model provides molecular insights into the rationale inhibitor design for developing an effective molecule against Fein-PX.


Assuntos
Moléculas de Adesão Celular/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Heme/antagonistas & inibidores , Penaeidae/metabolismo , beta-Glucanas/farmacologia , Animais , Catecol Oxidase/metabolismo , Moléculas de Adesão Celular/antagonistas & inibidores , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/metabolismo , Clonagem Molecular , Simulação por Computador , Precursores Enzimáticos/metabolismo , Técnicas In Vitro , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Penaeidae/química , Penaeidae/genética , Filogenia , Relação Estrutura-Atividade
11.
Arch Biochem Biophys ; 596: 10-21, 2016 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-26926257

RESUMO

The genome of Leishmania donovani, the causative agent of visceral leishmaniasis, codes for approximately 65% of both conserved and non-conserved hypothetical proteins. Studies on 'conserved hypothetical' proteins are expected to reveal not only new and crucial aspects of Leishmania biochemistry, but it could also lead to discovery of novel drug candidates. Conserved hypothetical protein, LdBPK_070020, is a 31.14 kDa protein, encoded by an 810 bp gene. BLAST analysis of LdBPK_070020, performed against NCBI non-redundant database, showed 80-99% similarity with conserved hypothetical proteins of Leishmania belonging to other species. Using homologues recombination method, we have performed gene knockout of LdBPK_070020 and effects of the same were investigated on the parasite. The gene knocked out strain shows significant retardation in growth with respect to wild type. Detailed biochemical studies indicated towards important role of LdBPK_070020 in the parasite survival and growth.


Assuntos
Leishmania donovani , Bases de Dados de Proteínas , Técnicas de Silenciamento de Genes , Leishmania donovani/genética , Leishmania donovani/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Análise de Sequência de Proteína
12.
Biotechnol Appl Biochem ; 63(6): 779-788, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26466758

RESUMO

Prophenoloxidase (ProPO) cascade is a principal defense system in crustaceans, which consists of a variety of pattern recognition proteins (lipopolysaccharide and ß-glucan-binding protein [ß-GBP], ß-GBP, and ß-glucan recognition protein), proteases (serine protease), and protease inhibitors (α2-macroglobulin and pacifastin) to regulate the protection mechanism in crustaceans. In the prophneoloxidase pathway, the protein-protein interactions (PPIs) and other immune-related analyses still have not been reported. Moreover, the structural features of ProPO cascade proteins have not yet been reported, hence we constructed the three-dimensional structural features for all ProPO pathway proteins. Their PPIs were studied through an in silico approach. Laminarin has been identified as a triggering activator and it showed energetic binding with homology modeled ß-GBP and activated the ß-GBP, followed by the protein-protein complex formation leading to phenoloxidase synthesis. These findings provided a novel view of the ProPO mechanism and enhanced our knowledge of the innate immune system in crustaceans via computation. In conclusion, we propose a combined experimental and computational approach to analyze the mechanism of ProPO cascade proteins.


Assuntos
Catecol Oxidase/metabolismo , Precursores Enzimáticos/metabolismo , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Mapeamento de Interação de Proteínas , Animais , Braquiúros/enzimologia , Catecol Oxidase/química , Precursores Enzimáticos/química , Ligantes , Conformação Proteica , beta-Glucanas/metabolismo
13.
J Chem Inf Model ; 55(8): 1686-97, 2015 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-26270943

RESUMO

Calpains belong to the family of calcium-dependent, structurally related intracellular cysteine proteases that exhibit significant functions in evolution of different types of cataracts in human as well as animal models. Application of calpain inhibitors generated through a virtual screening workflow may provide new avenues for the prevention of cataractogenesis. Hence, in the current study, compounds were first screened for potent calpain inhibitory activity by employing a structure-based approach, and the screening results were then validated through biological experiments in rat lenses. A hit compound, HTS08688, was obtained by structure-based virtual screening. A micromolar concentration of HTS08688 was found to prevent in vitro cataractogenesis in isolated Wistar rat lenses, while maintaining the antioxidant and calcium concentrations at near normal levels. Inhibition of superoxide anion generation, as observed through cytochemical localization studies, and maintenance of structural integrity, as demonstrated by histological analysis of lenticular tissue, also suggested that HTS08688 can ameliorate the cataractous condition induced by selenite in an in vitro rodent model. A cell proliferation assay was performed; the IC 50 value of the screened calpain inhibitor, HTS08688, against human lenticular epithelial cells-b3 was found to be 177 µM/mL. This combined theoretical and experimental approach has demonstrated a potent lead compound, HTS08688, that exhibits putative anticataractogenic activity by virtue of its potential to inhibit calpain.


Assuntos
Calpaína/antagonistas & inibidores , Catarata/prevenção & controle , Inibidores de Cisteína Proteinase/química , Inibidores de Cisteína Proteinase/uso terapêutico , Cristalino/efeitos dos fármacos , Animais , Cálcio/metabolismo , Calpaína/química , Calpaína/metabolismo , Catarata/metabolismo , Catarata/patologia , Linhagem Celular , Cristalografia por Raios X , Descoberta de Drogas , Humanos , Cristalino/metabolismo , Cristalino/patologia , Modelos Moleculares , Conformação Proteica , Ratos Wistar , Ácido Selenioso
14.
Biotechnol Appl Biochem ; 62(3): 416-23, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25066826

RESUMO

A full-length cDNA of a ß-glucan binding protein (ß-GBP) gene was identified from the mangrove crab Episesarma tetragonum. The open reading frame of the E. tetragonum ß-GBP (Epte ß-GBP) is 1,167 bp long, encoding a polypeptide of 389 amino acids. The deduced amino acid sequence of Epte ß-GBP gene has conserved a potential recognition motif for ß-1,3 linkages of polysaccharides and putative RGD (Arg-Gly-Asp) cell adhesion sites. Phylogenetic analysis of the Epte ß-GBP gene showed the similarity with ß-GBPs of other crustaceans and arthropods. Quantitative RT-PCR results showed the upregulation of Epte ß-GBP gene expression in E. tetragonum hemocytes following a 12-H challenge in response to ß-glucan (ß-G). Epte ß-GBP was involved in the regulation and activation of the prophenoloxidase cascade. A three-dimensional structure of active Epte ß-GBP was modeled by homology modeling and refined with molecular dynamics simulations. A structural aspect of the protein is discussed based on experimental and theoretical results obtained.


Assuntos
Braquiúros/genética , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Clonagem Molecular/métodos , Lectinas/química , Lectinas/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Transporte/genética , Lectinas/genética , Simulação de Acoplamento Molecular , Dados de Sequência Molecular
15.
J Mol Recognit ; 27(12): 696-706, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25319617

RESUMO

Retroviruses HTLV-1 and HIV-1 are the primary causative agents of fatal adult T-cell leukemia and acquired immune deficiency syndrome (AIDS) disease. Both retroviruses are similar in characteristics mechanism, and it encodes for protease that mainly involved in the viral replication process. On the basis of the therapeutic success of HIV-1 PR inhibitors, the protease of HTLV-1 is mainly considered as a potential target for chemotherapy. At the same time, structural similarities in both enzymes that originate HIV PR inhibitors can also be an HTLV-1 PR inhibitor. But the expectations failed because of rejection of HIV PR inhibitors from the HTLV-1 PR binding pocket. In this present study, the reason for the HIV PR inhibitor rejection from the HTLV-1 binding site was identified through sequence analysis and molecular dynamics simulation method. Functional analysis of M37A mutation in HTLV PR clearly shows that the MET37 specificity and screening of potential inhibitors targeting MET37 is performed by using approved 90% similar HIV PR inhibitor compounds. From this approach, we report few compounds with a tendency to accept/donate electron specifically to an important site residue MET37 in HTLV-1 PR binding pocket.


Assuntos
Ácido Aspártico Endopeptidases/metabolismo , Protease de HIV/metabolismo , Simulação de Dinâmica Molecular , Proteínas Mutantes/química , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Teoria Quântica , Absorção Fisiológica/efeitos dos fármacos , Sequência de Aminoácidos , Ácido Aspártico Endopeptidases/química , Células CACO-2 , Domínio Catalítico , Análise Mutacional de DNA , Darunavir , Elétrons , Protease de HIV/química , Vírus Linfotrópico T Tipo 1 Humano/efeitos dos fármacos , Vírus Linfotrópico T Tipo 1 Humano/enzimologia , Humanos , Ligação de Hidrogênio , Dados de Sequência Molecular , Alinhamento de Sequência , Análise de Sequência de Proteína , Sulfonamidas/química , Sulfonamidas/farmacologia , Termodinâmica , Distribuição Tecidual/efeitos dos fármacos
16.
J Mol Recognit ; 27(4): 173-83, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24591174

RESUMO

In invertebrates, crustaceans' immune system consists of pattern recognition receptors (PRRs) instead of immunoglobulin's, which involves in the microbial recognition and initiates the protein-ligand interaction between hosts and pathogens. In the present study, PRRs namely ß-1,3 glucan binding protein (ß-GBP) from mangrove crab Episesarma tetragonum and its interactions with the pathogens such as bacterial and fungal outer membrane proteins (OMP) were investigated through microbial aggregation and computational interaction studies. Molecular recognition and microbial aggregation results of Episesarma tetragonum ß-GBP showed the specific binding affinity toward the fungal ß-1,3 glucan molecule when compared to other bacterial ligands. Because of this microbial recognition, prophenoloxidase activity was enhanced and triggers the innate immunity inside the host animal. Our findings disclose the role of ß-GBP in molecular recognition, host-pathogen interaction through microbial aggregation, and docking analysis. In vitro results were concurred with the in silico docking, and molecular dynamics simulation analysis. This study would be helpful to understand the molecular mechanism of ß-GBP and update the current knowledge on the PRRs of crustaceans.


Assuntos
Catecol Oxidase/genética , Membrana Celular/imunologia , Crustáceos/imunologia , Precursores Enzimáticos/genética , Interações Hospedeiro-Patógeno/imunologia , Sistema Imunitário , Animais , Bactérias/imunologia , Bactérias/patogenicidade , Proteínas de Transporte/genética , Proteínas de Transporte/imunologia , Membrana Celular/enzimologia , Membrana Celular/microbiologia , Interações Hospedeiro-Patógeno/genética , Lectinas/genética , Lectinas/imunologia , Receptores de Reconhecimento de Padrão/genética , Receptores de Reconhecimento de Padrão/imunologia
17.
J Mol Recognit ; 27(2): 106-16, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24436128

RESUMO

The LuxS-based signalling pathway has an important role in physiological and pathogenic functions that are capable of causing different infections. In the present study, cinnamaldehyde (CN) and their derivatives were evaluated for their inhibitory efficiency against LuxS by molecular modelling, docking, dynamics and free-energy calculations. Sequence and structure-similarity analysis of LuxS protein, five different amino acids were found to be highly conserved, of which GLY128 was identified as the key residue involved in the effective binding of the ligands. Quantum-polarized ligand docking protocol showed that 2nitro and 4nitro CN has a higher binding efficiency than CN, which very well corroborates with the in vitro studies. COMSTAT analysis for the microscopic images of the S. pyogenes biofilm showed that the ligands have antibiofilm potential. In addition, the results of quantitative polymerase chain reaction (qPCR) analysis revealed that the transcripts treated with the compounds showed decrease in luxS expression, which directly reflects with the reduction in expression of speB. No substantial effect was observed on the virulence regulator (srv) transcript. These results confirm that speB is controlled by the regulation of luxS. The decreased rate of S. pyogenes survival in the presence of these ligands envisaged the fact that the compounds could readily enhance opsonophagocytosis with the reduction of virulence factor secretion. Thus, the overall data supports the use of CN derivatives against quorum sensing-mediated infections caused by S. pyogenes.


Assuntos
Acroleína/análogos & derivados , Proteínas de Bactérias/química , Biofilmes/efeitos dos fármacos , Liases de Carbono-Enxofre/química , Streptococcus pyogenes/efeitos dos fármacos , Acroleína/química , Sequência de Aminoácidos , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Biofilmes/crescimento & desenvolvimento , Liases de Carbono-Enxofre/biossíntese , Liases de Carbono-Enxofre/genética , Simulação por Computador , Regulação Bacteriana da Expressão Gênica , Simulação de Acoplamento Molecular , Percepção de Quorum/efeitos dos fármacos , Transdução de Sinais/genética , Streptococcus pyogenes/patogenicidade , Relação Estrutura-Atividade , Virulência/genética
18.
J Mol Recognit ; 27(7): 429-37, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24895275

RESUMO

The recognition of DNA by small molecules is of special importance in the design of new drugs. Many natural and synthetic compounds have the ability to interact with the minor groove of DNA. In the present study, identification of minor groove binding compounds was attained by the combined approach of pharmacophore modelling, virtual screening and molecular dynamics approach. Experimentally reported 32 minor groove binding compounds were used to develop the pharmacophore model. Based on the fitness score, best three pharmacophore hypotheses were selected and used as template for screening the compounds from drug bank database. This pharmacophore-based screening provides many compounds with the same pharmacological properties. All these compounds were subjected to four phases of docking protocols with combined Glide-quantum-polarized ligand docking approach. Molecular dynamics results indicated that selected compounds are more active and showed good interaction in the binding site of DNA. Based on the scoring parameters and energy values, the best compounds were selected, and antibacterial activity of these compounds was identified using in vitro antimicrobial techniques.


Assuntos
DNA/química , Simulação de Acoplamento Molecular , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade , Sítios de Ligação , Ligantes , Modelos Moleculares , Simulação de Dinâmica Molecular
19.
J Recept Signal Transduct Res ; 34(3): 221-32, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24490975

RESUMO

Members of the sortase enzyme super family decorate the surfaces of Bacillus anthracis cell wall with proteins that play key roles in microbial pathogenesis and its biofilm formation. Bacillus anthracis Sortase-A (Ba-SrtA) is a potential target for new therapeutics as it is required for B. anthracis survival and replication within macrophages. An understanding of the binding site pocket and substrate recognition mechanism by SrtA enzymes may serve to be beneficial in the rational development of sortase inhibitors. Here, the LPXTG signal peptide-based competitive inhibitors are screened against the Ba-SrtA and compounds with reasonable inhibition, specificity, and mechanisms of inactivation of SrtA have been covered. The screened compounds are experimentally validated against the phylogenetically similar Gram-positive pathogen B. cereus. In situ microscopic visualizations suggest that these screened compounds showed the microbial and biofilm inhibitory activity against B. cereus. It facilitates the further development of these molecules into useful anti-infective agents to treat infections caused by B. anthracis and other Gram-positive pathogens. These results provide insight into basic design principles for generating new clinically relevant lead molecules. It also provides an alternative strategy where a screened ligand molecule can be used in combination to battle increasingly against the Gram-positive pathogens.


Assuntos
Aminoaciltransferases/antagonistas & inibidores , Aminoaciltransferases/metabolismo , Bacillus anthracis/fisiologia , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/metabolismo , Cisteína Endopeptidases/metabolismo , Modelos Químicos , Peptídeos/química , Peptídeos/farmacologia , Transdução de Sinais/fisiologia , Antibacterianos/química , Antibacterianos/farmacologia , Bacillus anthracis/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Simulação por Computador , Avaliação Pré-Clínica de Medicamentos , Transdução de Sinais/efeitos dos fármacos
20.
J Recept Signal Transduct Res ; 34(5): 361-71, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24694004

RESUMO

Retroviruses are most perilous viral family, which cause much damage to the Homo sapiens. HTLV-1 mechanism found to more similar with HIV-1 and both retroviruses are causative agents of severe and fatal diseases including adult T-cell leukemia (ATL) and the acquired immune deficiency syndrome (AIDS). Both viruses code for a protease (PR) that is essential for replication and therefore represents a key target for drugs interfering with viral infection. In this work, the comparative study of HIV-1 and HTLV-1 PR enzymes through sequence and structural analysis is reported along with approved drugs of HIV-PR. Conformation of each HIV PR drugs have been examined with different parameters of interactions and energy scorings parameters. MD simulations with respect to timescale event of 20 ns favors that, few HIV-PR inhibitors can be more active inside the HTLV-1 PR binding pocket. Overall results suggest that, some of HIV inhibitors like Tipranavir, Indinavir, Darunavir and Amprenavir are having good energy levels with HTLV-1. Due to absence of interactions with MET37, here we report that derivatives of these compounds can be much better inhibitors for targeting HTLV-1 proteolytic activity.


Assuntos
Ácido Aspártico Endopeptidases/química , Ácido Aspártico Endopeptidases/ultraestrutura , Inibidores da Protease de HIV/química , Protease de HIV/química , Protease de HIV/ultraestrutura , Modelos Químicos , Simulação de Acoplamento Molecular/métodos , Sítios de Ligação , Simulação por Computador , Desenho de Fármacos , Ativação Enzimática , Ligação Proteica , Conformação Proteica , Mapeamento de Interação de Proteínas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA