Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
BMC Biotechnol ; 23(1): 20, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37430266

RESUMO

The current study is focused on the lipid extract of microalgae; Pectinodesmus strain PHM3 and its general analysis in terms of chemical contents. Combinations of both chemical and mechanistic approaches were applied to obtain the maximum yield of lipids which was recorded to be 23% per gram through continuous agitation using Folch solution. The extraction methods used in this study included: Bligh and Dyers method, Continuous agitation method, Extraction using Soxhlet and Acid base extraction method. Lipid quantification of ethanol and Folch solution lipid extract was performed through gravimetric methods and qualification was done through Fourier Transmission Infrared Spectroscopy (FTIR) and Gas Chromatographymass spectrometry (GC-MS). Phytochemical analysis identified other compounds in ethanol extract and the results confirmed the presence of steroids, coumarins, tannins, phenols and carbohydrates. Transesterification of lipids showed 7% per gram dry weight yield of Pectinodesmus PHM3. GC-MS studies of extracted biodiesel suggested that 72% of biofuels was in the form of dipropyl ether, ethyl butyl ethers, methyl butyl ether and propyl butyl ether. Lipid processing of acid-base extract showed that oily nature of lipid shifted to a more precipitated form which is a common observation when mixture of lipids is converted to phosphatides.


Assuntos
Éteres Metílicos , Microalgas , Biocombustíveis , Etanol , Éteres , Etil-Éteres , Fosfolipídeos
2.
Mol Genet Genomics ; 298(1): 79-93, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36301366

RESUMO

Salinity severely affects crop yield by hindering nitrogen uptake and reducing plant growth. Plant growth-promoting bacteria (PGPB) are capable of providing cross-protection against biotic/abiotic stresses and facilitating plant growth. Genome-level knowledge of PGPB is necessary to translate the knowledge into a product as efficient biofertilizers and biocontrol agents. The current study aimed to isolate and characterize indigenous plant growth-promoting strains with the potential to promote plant growth under various stress conditions. In this regard, 72 bacterial strains were isolated from various saline-sodic soil/lakes; 19 exhibited multiple in vitro plant growth-promoting traits, including indole 3 acetic acid production, phosphate solubilization, siderophore synthesis, lytic enzymes production, biofilm formation, and antibacterial activities. To get an in-depth insight into genome composition and diversity, whole-genome sequence and genome mining of one promising Bacillus paralicheniformis strain ES-1 were performed. The strain ES-1 genome carries 12 biosynthetic gene clusters, at least six genomic islands, and four prophage regions. Genome mining identified plant growth-promoting conferring genes such as phosphate solubilization, nitrogen fixation, tryptophan production, siderophore, acetoin, butanediol, chitinase, hydrogen sulfate synthesis, chemotaxis, and motility. Comparative genome analysis indicates the region of genome plasticity which shapes the structure and function of B. paralicheniformis and plays a crucial role in habitat adaptation. The strain ES-1 has a relatively large accessory genome of 649 genes (~ 19%) and 180 unique genes. Overall, these results provide valuable insight into the bioactivity and genomic insight into B. paralicheniformis strain ES-1 with its potential use in sustainable agriculture.


Assuntos
Bacillus , Sideróforos , Sideróforos/genética , Bacillus/genética , Bactérias/genética , Cloreto de Sódio , Antibacterianos , Fosfatos/farmacologia
3.
Sci Rep ; 12(1): 15648, 2022 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-36123370

RESUMO

Many PTMs dysregulation is known to be the major cause of many cancers including HCV induced HCC. PTMs of hepatitis C virus (HCV) regions NS3/4A, NS5A and NS5B are crucial for proper protein functions and replication that directly affect the generation of infectious virus particles and completion of its life cycle. In this study, we have performed comprehensive analysis of PTMs within HCV non-structural proteins (NS3/4A, NS5A and NS5B) through bioinformatics analysis to examine post-translational crosstalk between phosphorylation, palmitoylation, methylation, acetylation and ubiquitination sites in selected viral proteins. Our analysis has revealed many highly putative PTMs sites that are also conserved among major genotypes conferring the importance of these sites. We have also analysed viral 3D structures in their modified and unmodified forms to address extent and signatures of structural changes upon PTM. This study provides evidence that PTMs induce significant conformational changes and make viral proteins more stable. To find the potential role of PTMs in HCV induced HCC, docking analysis between selected viral proteins and p38-MAPK has been performed which also confirms their strong association with HCV induced HCC. The major findings proposed that PTMs at specific sites of HCV viral proteins could dysregulate specific pathways that cause the development of HCC.


Assuntos
Carcinoma Hepatocelular , Hepatite C , Neoplasias Hepáticas , Hepacivirus/genética , Hepatite C/complicações , Humanos , Processamento de Proteína Pós-Traducional , Proteínas Virais/genética
4.
Front Oncol ; 12: 875188, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35686109

RESUMO

Chemotherapy resistance and peculiar tumor microenvironment, which diminish or mitigate the effects of therapies, make pancreatic cancer one of the deadliest malignancies to manage and treat. Advanced immunotherapies are under consideration intending to ameliorate the overall patient survival rate in pancreatic cancer. Oncolytic viruses therapy is a new type of immunotherapy in which a virus after infecting and lysis the cancer cell induces/activates patients' immune response by releasing tumor antigen in the blood. The current review covers the pathways and molecular ablation that take place in pancreatic cancer cells. It also unfolds the extensive preclinical and clinical trial studies of oncolytic viruses performed and/or undergoing to design an efficacious therapy against pancreatic cancer.

5.
J Glob Antimicrob Resist ; 29: 293-295, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35413450

RESUMO

OBJECTIVES: The present study describes the draft genome sequence of a novel Bacillus sp. strain SD-4 isolated from animal feed. The study aims to get a deeper insight into antimicrobial resistance and secondary metabolite biosynthetic gene clusters (BGCs) and the association between them. METHODS: The strain SD-4 was preliminarily evaluated for antibacterial activities, motility, biofilm formation, and enterotoxin production using in vitro assays. The genome of strain SD-4 was sequenced using the Illumina HiSeq 2500 platform with paired-end reads. The reads were assembled and annotated using SPAdes and PGAP, respectively. The genome was further analysed using several bioinformatics tools, including TYGS, AntiSMASH, RAST, PlasmidFinder, VFDB, VirulenceFinder, CARD, PathogenFinder, MobileElement finder, IslandViewer, and CRISPRFinder. RESULTS: In vitro assays showed that the strain is motile, synthesises biofilm, and produces an enterotoxin and antibacterial metabolites. The genome analysis revealed that the strain SD-4 carries antimicrobial resistance genes (ARGs), virulence factors, and beneficial secondary metabolite BGCs. Further genome analysis showed interesting genome architectures containing several mobile genetic elements, including two plasmid replicons (repUS22 and rep20), five prophages, and at least four genomic islands (GIs), including one Listeria pathogenicity island LIPI-1. Moreover, the strain SD-4 is identified as a putative human pathogen. CONCLUSION: The genome of strain SD-4 harbours several BGCs coding for biologically active metabolites. It also contains antimicrobial resistance genes and is identified as a potential human pathogen. These results can be used to better comprehend antibiotic resistance in environmental bacteria that are not influenced by human intervention.


Assuntos
Bacillus , Ração Animal , Animais , Antibacterianos/farmacologia , Bacillus/genética , Bovinos , Enterotoxinas , Genoma Bacteriano
6.
J Gen Virol ; 102(12)2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34850675

RESUMO

An extensive screening survey was conducted on Pakistani filamentous fungal isolates for the identification of viral infections. A total of 396 fungal samples were screened, of which 36 isolates were found double-stranded (ds) RNA positive with an overall frequency of 9% when analysed by a classical dsRNA isolation method. One of 36 dsRNA-positive strains, strain SP1 of a plant pathogenic fungus Fusarium mangiferae, was subjected to virome analysis. Next-generation sequencing and subsequent completion of the entire genome sequencing by a classical Sanger sequencing method showed the SP1 strain to be co-infected by 11 distinct viruses, at least seven of which should be described as new taxa at the species level according to the ICTV (International Committee on Taxonomy of Viruses) species demarcation criteria. The newly identified F. mangiferae viruses (FmVs) include two partitivirids, one betapartitivirus (FmPV1) and one gammapartitivirus (FmPV2); six mitovirids, three unuamitovirus (FmMV2, FmMV4, FmMV6), one duamitovirus (FmMV5), and two unclassified mitovirids (FmMV1, FmMV3); and three botourmiavirids, two magoulivirus (FmBOV1, FmBOV3) and one scleroulivirus (FmBOV2). The number of coinfecting viruses is among the largest ones of fungal coinfections. Their molecular features are thoroughly described here. This represents the first large virus survey in the Indian sub-continent.


Assuntos
Micovírus/genética , Fusarium/virologia , Micovírus/classificação , Micovírus/ultraestrutura , Fusarium/isolamento & purificação , Genoma Viral/genética , Paquistão , Filogenia , Doenças das Plantas/microbiologia , Plantas/microbiologia , Vírus de RNA/classificação , Vírus de RNA/genética , Vírus de RNA/ultraestrutura , RNA Viral/genética , Proteínas Virais/genética , Viroma/genética
7.
3 Biotech ; 11(12): 489, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34790513

RESUMO

In the current study, Chryseobacterium cucumeris strain MW-6 isolated from Arabian seawater exhibited broad-spectrum antibacterial activity against indicator bacterial pathogens. The partially extracted antibacterial metabolites with ethyl acetate revealed promising activity against Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Listeria monocytogenes, and Staphylococcus aureus. The minimum inhibitory concentrations (MICs) were determined against indicator strains that ranged from 65-90 µg/ml. The genome size of C. cucumeris MW-6 is 4.81 Mbs containing 4227 coding DNA sequences, 74 tRNAs, 3 rRNAs, and 3 ncRNAs genes with 36.90% GC contents. The genome harbors nine putative biosynthetic gene clusters (BGCs) involved in the biosynthesis of lanthipeptide, NRPS-like, RiPPs-like, terpene, microviridin, T1PKS (hg1E-KS), resorcinol, and siderophore. Additionally, the strain encodes genes for sodium/proton antiporter, glutathione, superoxide dismutase, and cold shock protein to survive under stress conditions such as osmotic, oxidative, and cold shock. These putative BGCs and stress-related genes can be associated with in-vitro antibacterial activities and adaptation of this strain to the marine environment. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-03039-5.

8.
Genes (Basel) ; 12(7)2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34356076

RESUMO

The present study reports the isolation of antibacterial exhibiting Bacillus pumilus (B. pumilus) SF-4 from soil field. The genome of this strain SF-4 was sequenced and analyzed to acquire in-depth genomic level insight related to functional diversity, evolutionary history, and biosynthetic potential. The genome of the strain SF-4 harbor 12 Biosynthetic Gene Clusters (BGCs) including four Non-ribosomal peptide synthetases (NRPSs), two terpenes, and one each of Type III polyketide synthases (PKSs), hybrid (NRPS/PKS), lipopeptide, ß-lactone, and bacteriocin clusters. Plant growth-promoting genes associated with de-nitrification, iron acquisition, phosphate solubilization, and nitrogen metabolism were also observed in the genome. Furthermore, all the available complete genomes of B. pumilus strains were used to highlight species boundaries and diverse niche adaptation strategies. Phylogenetic analyses revealed local diversification and indicate that strain SF-4 is a sister group to SAFR-032 and 150a. Pan-genome analyses of 12 targeted strains showed regions of genome plasticity which regulate function of these strains and proposed direct strain adaptations to specific habitats. The unique genome pool carries genes mostly associated with "biosynthesis of secondary metabolites, transport, and catabolism" (Q), "replication, recombination and repair" (L), and "unknown function" (S) clusters of orthologous groups (COG) categories. Moreover, a total of 952 unique genes and 168 exclusively absent genes were prioritized across the 12 genomes. While newly sequenced B. pumilus SF-4 genome consists of 520 accessory, 59 unique, and seven exclusively absent genes. The current study demonstrates genomic differences among 12 B. pumilus strains and offers comprehensive knowledge of the respective genome architecture which may assist in the agronomic application of this strain in future.


Assuntos
Antibacterianos/metabolismo , Bacillus pumilus/genética , Proteínas de Bactérias/metabolismo , Genoma Bacteriano , Família Multigênica , Peptídeo Sintases/genética , Filogenia , Proteínas de Bactérias/genética
9.
RNA Biol ; 18(1): 1-15, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32615049

RESUMO

Circular RNAs (circRNAs) are ubiquitously expressed, covalently closed rings, produced by pre-mRNA splicing in a reversed order during post-transcriptional processing. Circularity endows 3'-5'-linked circRNAs with stability and resistance to exonucleolytic degradation which raises the question whether circRNAs may be relevant as potential therapeutic targets or agents. High stability in biological systems is the most remarkable property and a major criterion for why circRNAs could be exploited for a range of RNA-centred medical applications. Even though various biological roles and regulatory functions of circRNAs have been reported, their in-depth study is challenging because of their circular structure and sequence-overlap with linear mRNA counterparts. Moreover, little is known about their role in viral infections and in antiviral immune responses. We believe that an in-depth and detailed understanding of circRNA mediated viral protein regulations will increase our knowledge of the biology of these novel molecules. In this review, we aimed to provide a comprehensive basis and overview on the biogenesis, significance and regulatory roles of circRNAs in the context of antiviral immune responses and viral infections including hepatitis C virus infection, hepatitis B virus infection, hepatitis delta virus infection, influenza A virus infection, Epstein-Barr virus infection, kaposi's sarcoma herpesvirus infection, human cytomegalovirus infection, herpes simplex virus infection, human immunodeficiency virus infection, porcine epidemic diarrhoea virus infection, ORF virus infection, avian leukosis virus infection, simian vacuolating virus 40 infection, transmissible gastroenteritis coronavirus infection, and bovine viral diarrhoea virus infection. We have also discussed the critical regulatory role of circRNAs in provoking antiviral immunity, providing evidence for implications as therapeutic agents and as diagnostic markers.


Assuntos
Interações Hospedeiro-Patógeno/fisiologia , Medicina de Precisão/métodos , RNA Circular/imunologia , Viroses/genética , Viroses/imunologia , Animais , Biomarcadores/análise , Doença das Mucosas por Vírus da Diarreia Viral Bovina/genética , Bovinos , Infecções por Coronavirus/genética , Infecções por Coronavirus/veterinária , Infecções por HIV/genética , Hepatite C/genética , Infecções por Herpesviridae/genética , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Influenza Humana/genética , Vírus de RNA/genética , RNA Circular/fisiologia , Suínos , Doenças dos Suínos/virologia
10.
Mater Sci Eng C Mater Biol Appl ; 100: 82-93, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30948119

RESUMO

An improved active packaging system was developed for fresh fruits using silver nanoparticles (AgNPs) coupled with calcium alginate (Ca-ALG). For the synthesis of AgNPs aqueous, ethanol and methanol extracts of Artemisia scoparia (AS) were used. These AgNP's were characterized using UV-Vis, SEM, EDS, AFM, FTIR and gel electrophoresis. Ethanol extract of AS (ASE) produced AgNPs with smallest size in comparison to aqueous AS (ASA) and methanol extract of AS (ASM). AgNPs synthesized from ASE had a size range of 12.0-23.3 nm and were tested on Human Corneal Epithelial Cells to evaluate their cytotoxicity. At 0.05 ng/mL of AgNP's concentration, no toxic effects were observed on the evaluated cell line. Therefore, 0.05 ng/mL of AgNPs mixed with edible coating of Ca-ALG were applied on strawberries and loquats as active coating to increase their shelf life. Significant improvement was observed in the quality parameters of strawberries and loquats such as microbial analysis, acidity loss, soluble solid content loss, weight loss and quality decay. Ca-ALG coating incorporated with AgNPs enhanced the shelf life of strawberries and loquats in comparison to no treatment and simple Ca-ALG coatings. This study provides an insight to food industry to extend the shelf life of fresh fruits using AgNP's formulated coatings.


Assuntos
Artemisia/química , Embalagem de Alimentos/métodos , Nanopartículas Metálicas/química , Prata/química , Artemisia/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Frutas/química , Frutas/microbiologia , Humanos , Concentração de Íons de Hidrogênio , Nanopartículas Metálicas/toxicidade , Extratos Vegetais/química
11.
Mikrochim Acta ; 186(2): 127, 2019 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-30684013

RESUMO

This study reports on a simple approach for the fabrication of an electrode modified with biocompatible C-dot wrapped ZnO nanoparticles for selective photoelectrochemical monitoring of H2O2 released from living cells. The biocompatibility of the ZnO nanoparticles was confirmed through in-vitro cellular testing using the MTT assay on Huh7 cell lines. The ZnO nanoparticles wrapped with dopamine-derived C-dots possess numerous catalytically active sites, excessive surface defects, good electrical conductivity, and efficient separation ability of photo-induced electrons and holes. These properties offer highly sensitive and selective non-enzymatic photo-electrochemical monitoring of H2O2 released from HeLa cells after stimulation with N-formylmethionyl-leucyl-phenylalanine. The sensor has a wide linear range (20-800 nM), low detection limit (2.4 nM), and reliable reproducibility, this implying its suitability for biological and biomedical applications. Graphical abstract Schematic of the fabrication of ZnO nanoparticles by using a plant extract as a reducing agent. Wrapping of ZnO with C-dots enhances the photoelectrocatalytic efficacy. Sensitive and selective photoelectrochemical monitoring of H2O2 released from cancer cells is demonstrated.


Assuntos
Carbono/química , Eletroquímica/instrumentação , Peróxido de Hidrogênio/metabolismo , Processos Fotoquímicos , Pontos Quânticos/química , Sobrevivência Celular , Eletrodos , Células HeLa , Humanos , Limite de Detecção , Óxido de Zinco/toxicidade
13.
Nanoscale Adv ; 1(8): 2924-2936, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-36133618

RESUMO

Semi-conductor quantum dots (QDs) are favorite candidates for many applications especially for potential use as optical bioimaging agents. But the major issue of QDs is toxicity. In the present study, carbon nanodots were synthesized using a green hydrothermal approach from gelatin protein using a previously established protocol. However, the PL properties and applications of the as-synthesized CG (bovine gelatin) nanodots were remarkably different from those of previously reported gelatin carbon dots. CG (bovine gelatin) nanodots had sizes greater than the Bohr exciton radius but still had QD like fluorescence characteristics. Furthermore, the results from fluorescence spectroscopy demonstrated a tunable PL emission profile at various excitation wavelengths. Second, carbon nanodots were also synthesized from algal biomass of Pectinodesmus sp. via a green hydrothermal approach, denoted as CA (PHM3 algae) nanodots. A study of the PL properties and surface chemical composition of CG (bovine gelatin) and CA (PHM3 algae) nanodots suggested that the surface chemical composition significantly alters the surface states which directly influence their PL properties. CG (bovine gelatin) nanodots were used for imaging of plant and bacterial cells with good imaging sensitivity comparable to toxic semiconductor quantum dots. Moreover, the results from in vitro studies suggested good anticancer properties of CA (PHM3 algae) and CG (bovine gelatin) nanodots with minimum GI50 values of 0.316 ± 0.447 ng ml-1 (n = 2) and 8.156 ± 6.596 ng ml-1 (n = 2) for HCC 1954 (breast cancer) and 0.542 ± 0.715 ng ml-1 (n = 2) and 23.860 ± 14.524 ng ml-1 (n = 2) for HCT 116 (colorectal cancer) cell lines, respectively.

14.
Sci Rep ; 8(1): 16107, 2018 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-30382118

RESUMO

Hepatitis C virus (HCV) vaccines, designed to augment specific T-cell responses, have been designated as an important aspect of effective antiviral treatment. However, despite the current satisfactory progress of these vaccines, extensive past efforts largely remained unsuccessful in mediating clinically relevant anti-HCV activity in humans. In this study, we used a series of immunoinformatics approaches to propose a multiepitope vaccine against HCV by prioritizing 16 conserved epitopes from three viral proteins (i.e., NS34A, NS5A, and NS5B). The prioritised epitopes were tested for their possible antigenic combinations with each other along with linker AAY using structural modelling and epitope-epitope interactions analysis. An adjuvant (ß-defensin) at the N-terminal of the construct was added to enhance the immunogenicity of the vaccine construct. Molecular dynamics (MD) simulation revealed the most stable structure of the proposed vaccine. The designed vaccine is potentially antigenic in nature and can form stable and significant interactions with Toll-like receptor 3 and Toll-like receptor 8. The proposed vaccine was also subjected to an in silico cloning approach, which confirmed its expression efficiency. These analyses suggest that the proposed vaccine can elicit specific immune responses against HCV; however, experimental validation is required to confirm the safety and immunogenicity profile of the proposed vaccine construct.


Assuntos
Biologia Computacional/métodos , Epitopos de Linfócito T/imunologia , Hepacivirus/imunologia , Hepatite C/imunologia , Vacinas de Subunidades Antigênicas/imunologia , Proteínas não Estruturais Virais/imunologia , Sequência de Aminoácidos , Hepatite C/prevenção & controle , Hepatite C/virologia , Humanos , Simulação de Dinâmica Molecular , Conformação Proteica , RNA Helicases/imunologia , Receptores Imunológicos/imunologia , Serina Endopeptidases/imunologia , Linfócitos T/imunologia , Vacinas de Subunidades Antigênicas/administração & dosagem
15.
Genes (Basel) ; 9(5)2018 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-29701718

RESUMO

Polio viral proteinase 2A performs several essential functions in genome replication. Its inhibition prevents viral replication, thus making it an excellent substrate for drug development. In this study, the three-dimensional structure of 2A protease was determined and optimized by homology modelling. To predict the molecular basis of the interaction of small molecular agonists, docking simulations were performed on a structurally diverse dataset of poliovirus 2A protease (PV2Apr°) inhibitors. Docking results were employed to identify high risk missense mutations that are highly damaging to the structure, as well as the function, of the protease. Intrinsic disorder regions (IDRs), drug binding sites (DBS), and protein stability changes upon mutations were also identified among them. Our results demonstrated dominant roles for Lys 15, His 20, Cys 55, Cys 57, Cys 64, Asp 108, Cys 109 and Gly 110, indicating the presence of various important drug binding sites of the protein. Upon subjecting these sites to single-nucleotide polymorphism (SNP) analysis, we observed that out of 155 high risk SNPs, 139 residues decrease the protein stability. We conclude that these missense mutations can affect the functionality of the 2A protease, and that identified protein binding sites can be directed for the attachment and inhibition of the target proteins.

16.
Sci Rep ; 7(1): 11448, 2017 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-28904393

RESUMO

Among solid tumors, hepatocellular carcinoma (HCC) emerges as a prototypical therapy-resistant tumor. Considering the emerging sorafenib resistance crisis in HCC, future studies are urgently required to overcome resistance. Recently noncoding RNAs (ncRNAs) have emerged as significant regulators in signalling pathways involved in cancer drug resistance and pharmacologically targeting these ncRNAs might be a novel stratagem to reverse drug resistance. In the current study, using a hybrid Petri net based computational model, we have investigated the harmonious effect of miR-17-92 cluster inhibitors/mimics and circular RNAs on sorafenib resistant HCC cells in order to explore potential resistance mechanisms and to identify putative targets for sorafenib-resistant HCC cells. An integrated model was developed that incorporates seven miRNAs belonging to miR-17-92 cluster (hsa-miR-17-5p, hsa-miR-17-3p, hsa-miR-19a, hsa-miR-19b, hsa-miR-18a, hsa-miR-20a and hsa-miR-92) and crosstalk of two signaling pathways (EGFR and IL-6) that are differentially regulated by these miRNAs. The mechanistic connection was proposed by the correlation between members belonging to miR-17-92 cluster and corresponding changes in the protein levels of their targets in HCC, specifically those targets that have verified importance in sorafenib resistance. Current findings uncovered potential pathway features, underlining the significance of developing modulators of this cluster to combat drug resistance in HCC.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , MicroRNAs/genética , Família Multigênica , Farmacogenética , Sorafenibe/farmacologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Regulação Neoplásica da Expressão Gênica , Genes erbB-1 , Humanos , Interleucina-6/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Transdução de Sinais
17.
Front Physiol ; 8: 416, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28659828

RESUMO

Cellular homeostasis is a continuous phenomenon that if compromised can lead to several disorders including cancer. There is a need to understand the dynamics of cellular proliferation to get deeper insights into the prevalence of cancer. Mechanistic Target of Rapamycin (mTOR) is implicated as the central regulator of the metabolic pathway involved in growth whereas its two distinct complexes mTORC1 and mTORC2 perform particular functions in cellular propagation. To date, mTORC1 is a well defined therapeutic target to inhibit uncontrolled cell division, while the role of mTORC2 is not well characterized. Therefore, the current study is designed to understand the signaling dynamics of mTOR and its partner proteins such as PI3K, PTEN, mTORC2, PKB (Akt), mTORC1, and FOXO. For this purpose, a qualitative model of mTOR-associated Biological Regulatory Network (BRN) is constructed to predict its regulatory behaviors which may not be predictable otherwise. The depleted expression of PTEN and FOXO along with the overexpression of PI3K, mTORC2, mTORC1 and Akt is predicted as a stable steady state which is in accordance with their observed expression levels in the progression of various cancers. The qualitative model also predicts the homeostasis of all the entities in the form of qualitative cycles. The significant qualitative (discrete) cycle is identified by analyzing betweenness centralities of the qualitative (discrete) states. This cycle is further refined as a linear hybrid automaton model with the production (activation) and degradation (inhibition) time delays in order to analyze the real-time constraints for its existence. The analysis of the hybrid model provides a formal proof that during homeostasis the inhibition time delay of Akt is less than the inhibition time delay of mTORC2. In conclusion, our observations characterize that in homeostasis Akt is degraded with a faster rate than mTORC2 which suggests that the inhibition of Akt along with the activation of mTORC2 may be a better therapeutic strategy for the treatment of cancer.

18.
Int J Mol Sci ; 18(1)2017 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-28085066

RESUMO

Autophagy, an evolutionary conserved multifaceted lysosome-mediated bulk degradation system, plays a vital role in liver pathologies including hepatocellular carcinoma (HCC). Post-translational modifications (PTMs) and genetic variations in autophagy components have emerged as significant determinants of autophagy related proteins. Identification of a comprehensive spectrum of genetic variations and PTMs of autophagy related proteins and their impact at molecular level will greatly expand our understanding of autophagy based regulation. In this study, we attempted to identify high risk missense mutations that are highly damaging to the structure as well as function of autophagy related proteins including LC3A, LC3B, BECN1 and SCD1. Number of putative structural and functional residues, including several sites that undergo PTMs were also identified. In total, 16 high-risk SNPs in LC3A, 18 in LC3B, 40 in BECN1 and 43 in SCD1 were prioritized. Out of these, 2 in LC3A (K49A, K51A), 1 in LC3B (S92C), 6 in BECN1 (S113R, R292C, R292H, Y338C, S346Y, Y352H) and 6 in SCD1 (Y41C, Y55D, R131W, R135Q, R135W, Y151C) coincide with potential PTM sites. Our integrated analysis found LC3B Y113C, BECN1 I403T, SCD1 R126S and SCD1 Y218C as highly deleterious HCC-associated mutations. This study is the first extensive in silico mutational analysis of the LC3A, LC3B, BECN1 and SCD1 proteins. We hope that the observed results will be a valuable resource for in-depth mechanistic insight into future investigations of pathological missense SNPs using an integrated computational platform.


Assuntos
Proteínas Relacionadas à Autofagia/química , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Mutação de Sentido Incorreto , Relação Quantitativa Estrutura-Atividade , Sequência de Aminoácidos , Sítios de Ligação , Carcinoma Hepatocelular/metabolismo , Biologia Computacional/métodos , Sequência Conservada , Bases de Dados Genéticas , Conjuntos de Dados como Assunto , Evolução Molecular , Humanos , Neoplasias Hepáticas/metabolismo , Modelos Moleculares , Fosforilação , Polimorfismo de Nucleotídeo Único , Ligação Proteica , Conformação Proteica , Processamento de Proteína Pós-Traducional
19.
Antiviral Res ; 137: 112-124, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27984060

RESUMO

Cellular immune responses (T cell responses) during hepatitis C virus (HCV) infection are significant factors for determining the outcome of infection. HCV adapts to host immune responses by inducing mutations in its genome at specific sites that are important for HLA processing/presentation. Moreover, HCV also adapts to resist potential drugs that are used to restrict its replication, such as direct-acting antivirals (DAAs). Although DAAs have significantly reduced disease burden, resistance to these drugs is still a challenge for the treatment of HCV infection. Recently, drug resistance mutations (DRMs) observed in HCV proteins (NS3/4A, NS5A and NS5B) have heightened concern that the emergence of drug resistance may compromise the effectiveness of DAAs. Therefore, the NS3/4A, NS5A and NS5B drug resistance variations were investigated in this study, and their prevalence was examined in a large number of protein sequences from all HCV genotypes. Furthermore, potential CD4+ and CD8+ T cell epitopes were predicted and their overlap with genetic variations was explored. The findings revealed that many reported DRMs within NS3/4A, NS5A and NS5B are not drug-induced; rather, they are already present in HCV strains, as they were also detected in HCV-naïve patients. This study highlights several hot spots in which HLA and drug selective pressure overlap. Interestingly, these overlapping mutations were frequently observed among many HCV genotypes. This study implicates that knowledge of the host HLA type and HCV subtype/genotype can provide important information in defining personalized therapy.


Assuntos
Farmacorresistência Viral/genética , Variação Genética , Hepacivirus/genética , Proteínas não Estruturais Virais/genética , Antivirais/farmacologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Bases de Dados Genéticas , Epitopos de Linfócito T/genética , Genótipo , Antígenos HLA , Hepacivirus/efeitos dos fármacos , Hepacivirus/imunologia , Hepatite C/imunologia , Hepatite C/virologia , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/imunologia , Hepatite C Crônica/virologia , Humanos , Mutação de Sentido Incorreto , Medicina de Precisão/métodos , Inibidores de Proteases/farmacologia
20.
BMC Genomics ; 17(1): 732, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27634541

RESUMO

BACKGROUND: Acinetobacter baumannii has emerged as a significant nosocomial pathogen during the last few years, exhibiting resistance to almost all major classes of antibiotics. Alternative treatment options such as vaccines tend to be most promising and cost effective approaches against this resistant pathogen. In the current study, we have explored the pan-genome of A. baumannii followed by immune-proteomics and reverse vaccinology approaches to identify potential core vaccine targets. RESULTS: The pan-genome of all available A. baumannii strains (30 complete genomes) is estimated to contain 7,606 gene families and the core genome consists of 2,445 gene families (~32 % of the pan-genome). Phylogenetic tree, comparative genomic and proteomic analysis revealed both intra- and inter genomic similarities and evolutionary relationships. Among the conserved core genome, thirteen proteins, including P pilus assembly protein, pili assembly chaperone, AdeK, PonA, OmpA, general secretion pathway protein D, FhuE receptor, Type VI secretion system OmpA/MotB, TonB dependent siderophore receptor, general secretion pathway protein D, outer membrane protein, peptidoglycan associated lipoprotein and peptidyl-prolyl cis-trans isomerase are identified as highly antigenic. Epitope mapping of the target proteins revealed the presence of antigenic surface exposed 9-mer T-cell epitopes. Protein-protein interaction and functional annotation have shown their involvement in significant biological and molecular processes. The pipeline is validated by predicting already known immunogenic targets against Gram negative pathogen Helicobacter pylori as a positive control. CONCLUSION: The study, based upon combinatorial approach of pan-genomics, core genomics, proteomics and reverse vaccinology led us to find out potential vaccine candidates against A. baumannii. The comprehensive analysis of all the completely sequenced genomes revealed thirteen putative antigens which could elicit substantial immune response. The integration of computational vaccinology strategies would facilitate in tackling the rapid dissemination of resistant A.baumannii strains. The scarcity of effective antibiotics and the global expansion of sequencing data making this approach desirable in the development of effective vaccines against A. baumannii and other bacterial pathogens.


Assuntos
Acinetobacter baumannii/genética , Acinetobacter baumannii/metabolismo , Genoma Bacteriano , Genômica , Proteoma , Proteômica , Acinetobacter baumannii/classificação , Acinetobacter baumannii/imunologia , Sequência de Aminoácidos , Antígenos de Bactérias/química , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/metabolismo , Biologia Computacional/métodos , Mapeamento de Epitopos , Epitopos/química , Epitopos/genética , Epitopos/imunologia , Evolução Molecular , Genômica/métodos , Modelos Moleculares , Anotação de Sequência Molecular , Peptídeos/química , Peptídeos/genética , Peptídeos/imunologia , Peptídeos/metabolismo , Filogenia , Conformação Proteica , Mapeamento de Interação de Proteínas , Mapas de Interação de Proteínas , Proteômica/métodos , Vacinas de Subunidades Antigênicas/genética , Vacinas de Subunidades Antigênicas/imunologia , Virulência/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...