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1.
Clin Microbiol Rev ; 36(4): e0008823, 2023 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-38032192

RESUMO

Tuberculosis (TB) is a major global health problem and the second most prevalent infectious killer after COVID-19. It is caused by Mycobacterium tuberculosis (Mtb) and has become increasingly challenging to treat due to drug resistance. The World Health Organization declared TB a global health emergency in 1993. Drug resistance in TB is driven by mutations in the bacterial genome that can be influenced by prolonged drug exposure and poor patient adherence. The development of drug-resistant forms of TB, such as multidrug resistant, extensively drug resistant, and totally drug resistant, poses significant therapeutic challenges. Researchers are exploring new drugs and novel drug delivery systems, such as nanotechnology-based therapies, to combat drug resistance. Nanodrug delivery offers targeted and precise drug delivery, improves treatment efficacy, and reduces adverse effects. Along with nanoscale drug delivery, a new generation of antibiotics with potent therapeutic efficacy, drug repurposing, and new treatment regimens (combinations) that can tackle the problem of drug resistance in a shorter duration could be promising therapies in clinical settings. However, the clinical translation of nanomedicines faces challenges such as safety, large-scale production, regulatory frameworks, and intellectual property issues. In this review, we present the current status, most recent findings, challenges, and limiting barriers to the use of emulsions and nanoparticles against drug-resistant TB.


Assuntos
Mycobacterium tuberculosis , Nanopartículas , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Preparações Farmacêuticas , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Sistemas de Liberação de Medicamentos
2.
Metabolites ; 13(1)2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36677054

RESUMO

As a complex endocrine and metabolic condition, polycystic ovarian syndrome (PCOS) affects women's reproductive health. These common symptoms include hirsutism, hyperandrogenism, ovulatory dysfunction, irregular menstruation, and infertility. No one knows what causes it or how to stop it yet. Alterations in gut microbiota composition and disruptions in secondary bile acid production appear to play a causative role in developing PCOS. PCOS pathophysiology and phenotypes are tightly related to both enteric and vaginal bacteria. Patients with PCOS exhibit changed microbiome compositions and decreased microbial diversity. Intestinal microorganisms also alter PCOS patient phenotypes by upregulating or downregulating hormone release, gut-brain mediators, and metabolite synthesis. The human body's gut microbiota, also known as the "second genome," can interact with the environment to improve metabolic and immunological function. Inflammation is connected to PCOS and may be caused by dysbiosis in the gut microbiome. This review sheds light on the recently discovered connections between gut microbiota and insulin resistance (IR) and the potential mechanisms of PCOS. This study also describes metabolomic studies to obtain a clear view of PCOS and ways to tackle it.

3.
Food Funct ; 14(1): 319-334, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36503930

RESUMO

An upsurge in early onset of photoaging due to repeated skin exposure to environmental stressors such as UV radiation is a challenge for pharmaceutical and cosmeceutical divisions. Current reports indicate severe side effects because of chemical or synthetic inhibitors of matrix metalloproteases (MMPs) in anti-skin aging cosmeceuticals. We evaluated the adequacy of bixin, a well-known FDA certified food additive, as a scavenger of free radicals and its inhibitory mechanism of action on MMP1, collagenase, elastase, and hyaluronidase. The anti-skin aging potential of bixin was evaluated by several biotechnological tools in silico, in vitro and in vivo. Molecular docking and simulation dynamics studies gave a virtual insight into the robust binding interaction between bixin and skin aging-related enzymes. Absorbance and fluorescence studies, enzyme inhibition assays, enzyme kinetics and in vitro bioassays of human dermal fibroblast (HDF) cells highlighted bixin's role as a potent antioxidant and inhibitor of skin aging-related enzymes. Furthermore, in vivo protocols were carried out to study the impact of bixin administration on UVA induced photoaging in C57BL/6 mice skin. Here, we uncover the UVA shielding effect of bixin and its efficacy as a novel anti-photoaging agent. Furthermore, the findings of this study provide a strong foundation to explore the pharmaceutical applications of bixin in several other biochemical pathways linked to MMP1, collagenase, elastase, and hyaluronidase.


Assuntos
Corantes de Alimentos , Dermatopatias , Animais , Humanos , Camundongos , Colagenases , Fibroblastos/metabolismo , Hialuronoglucosaminidase/metabolismo , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Elastase Pancreática , Raios Ultravioleta/efeitos adversos
4.
Life Sci ; 311(Pt A): 121118, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36404489

RESUMO

Gut microbial profiles induce cancer growth and impact treatment effectiveness, tolerance, and safety. There is still more to discover about the relationship between diseases and the microbiota and its clinical consequences. Even though much of the study is still in its early phases, the 'omics' technologies were widely used for microbiome analysis due to the increased size of datasets available in public databases. However, recognizing the potential of these new technologies is difficult at times, limiting our ability to analyze a vast amount of available data critically. In this context, two subsets of AI methods, Machine Learning (ML) and Deep Learning (DL), can aid clinicians in analyzing and comprehending these large datasets. Here, we reviewed the most up-to-date ML methodologies, databases, and tools used in human microbiome research. The proposed review forecast the use of ML in microbiome research involving associations and clinical applications for diagnostics, prognostics, and therapies.


Assuntos
Microbioma Gastrointestinal , Microbiota , Neoplasias , Humanos , Aprendizado de Máquina
5.
Chem Biodivers ; 19(12): e202200662, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36261320

RESUMO

The inhibition of phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) protein could be a promising treatment for breast cancer. In this regard, docking studies were accomplished on various functionalized organic molecules. Among them, several derivatives of quinazolin-4(1H)-one exhibited anti-breast cancer activity and satisfied the drug likeliness properties. Further, the in vitro inhibitory studies by a series of 2-(2-phenoxyquinolin-3-yl)-2,3-dihydroquinazolin-4(1H)-one molecules showed strong anti-cancer activity than the currently available drug, wortmannin. The MTT cytotoxicity assay was used to predict the anti-proliferative activity of these drugs against MCF-7 cancer cells by inhibiting the PIK3CA protein. The dose-dependent analysis showed a striking decrease in cancer cell viability at 24 h with inhibitory concentrations (IC50 ) of 3b, 3c, 3d, 3f and 3m are 15±1, 17±1, 8±1, 10±1 and 60±1 (nanomoles), respectively. This is the first report in the literature on the inhibition of PIK3CA protein by quinazolinone derivatives that can be used in the treatment of cancer. Quinazolinone analogs have the potential to be safe and economically feasible scaffolds if they are produced using a chemical technique that is both straightforward and amenable to modification. From the cancer research perspective, this study can eventually offer better care for cancer patients.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Relação Estrutura-Atividade , Proliferação de Células , Simulação de Acoplamento Molecular , Antineoplásicos/química , Quinazolinonas , Estrutura Molecular , Ensaios de Seleção de Medicamentos Antitumorais , Relação Dose-Resposta a Droga
6.
Comput Biol Med ; 139: 104946, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34715554

RESUMO

K-Ras mutations are frequent in various cancer types, and according to recent research, K-Ras possesses four-drug targeting sites. This increased our interest in finding potential small molecule inhibitors with anticancer activity to treat K-Ras-driven cancers. We utilized integrated bioinformatic strategies, such as XP docking, MM-GBSA, cell-line cytotoxicity prediction, ADMET, and molecular simulation, to discover potential inhibitors of G12C and G12D mutants compared to sotorasib, which is a recent FDA-approved inhibitor of G12C. We identified compounds, such as flupentixol, amlodipine, and fluvoxamine, for the G12C mutant and paroxetine, flupentixol, and zuclopenthixol for the G12D mutant with significant inhibitory functions. All five compounds bound to the H95 cryptic groove of mutant K-Ras with high efficiency and, like sotorasib, retained a novel binding mechanism with additional hydrophobic interactions at the molecular level. Furthermore, the simulation studies suggested that the binding of flupentixol and amlodipine to G12C stabilizes switch I and switch II. In contrast, paroxetine and flupentixol to G12D showed a similar trend compared to sotorasib complexes. Thus, despite the very dynamic functionality of K-Ras switches I and II, the binding of shortlisted compounds is highly stable. Therefore, the reported study provides potential drug candidates for K-Ras inhibition that can be further developed with in vitro and in vivo evidence for targeted therapy.


Assuntos
GTP Fosfo-Hidrolases , Neoplasias , Humanos , Vírus do Sarcoma Murino de Kirsten , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética
7.
J Cell Biochem ; 122(11): 1625-1638, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34289159

RESUMO

Genome-wide association studies (GWAS) have identified an association between polymorphisms in the FTO gene and obesity. The FTO: rs9939609, an intronic variant, is considered a risk allele for developing diabesity in homozygous and heterozygous forms. This study aimed to investigate the molecular structure of the available inhibitors specific to the FTO mutations along with the rs9939609 variant. We identified the best-suited inhibitor molecules for each mutant type containing the rs9939609 risk allele. Missense mutations unique to obesity and containing the risk allele of rs9939609 were retrieved from dbSNP for this study. Further stability testing for the mutations were carried out using DynaMut and iStable tools. Three mutations (G187A, M223V, and I492V) were highly destabilizing the FTO structure. These three mutants and native FTO were docked with each of the nine-inhibitor molecules collected from literature studies with the help of PyRx and AutoDock. Further structural behavior of the mutants and native FTO were identified with molecular dynamics simulations and MM-PBSA analyses, along with the 19complex inhibitor compound. We found the compound 19complex exhibited better binding interactions and is the top candidate inhibitor for the M223V and I492V mutants. This study provided insights into the structural changes caused due to mutations in FTO, and the binding mechanism of the inhibitor molecules. It could aid in developing antiobesity drugs for treating patients with mutations and risk alleles predisposing to obesity.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato/antagonistas & inibidores , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Obesidade/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/química , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Mutação , Polimorfismo de Nucleotídeo Único , Estabilidade Proteica
8.
Comput Biol Med ; 135: 104597, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34237589

RESUMO

The mutant K-Ras with aberrant signaling is the primary cause of several cancers. The proposed study investigated the influence of water molecules in K-Ras crystal structure, where they have a significant function by understanding their residue interaction networks (RINs). We analyzed the RINs of K-Ras with and without water molecules and determined their interaction properties. RINs were developed with the help of StructureViz2 and RINspector; further, the changes in K-Ras backbone flexibility were predicted with the DynaMine. We found that the residues K42, I142, and L159 are the hotspots from water, including the K-Ras-GTP complex with the highest residue centrality analysis (RCA) Z-score. The DynaMine prediction calculated the NMR S2 value for the frequently mutated positions G12, G13, and Q61 showing a minor shift in flexibility, which make up the P-Loop and switch II of the K-Ras protein. This flexibility shift can account for changes in conformational activity and the protein's GTPase activity, making it difficult to recognize by the effectors and exchange factors. Taken together, our study helps in understanding the functional importance of the water molecules in K-Ras protein and the impact of mutation that modulate the conformational state of the protein.


Assuntos
Água , Proteínas ras , Domínio AAA , Mutação , Transdução de Sinais , Proteínas ras/metabolismo
9.
Environ Res ; 200: 111759, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34310969

RESUMO

The recent upsurge of antibiotic-resistant infections has posed to be a serious health concern worldwide. In the present paper, the effect of shape & capping agent on the antibacterial activity (on Skin and Urinary Tract Infection (UTI) causing bacteria) of copper iodide (CuI) particles was probed. CuI synthesized without a capping agent was leaf-like, and that with one was prismatic in shape. XRD of the synthesized CuI confirmed their high crystalline nature and purity. The average crystallite sizes of capped and uncapped CuI were calculated to be 91.10 nm and 89.01 nm respectively from X-Ray powder diffraction data. The average particle size of capped CuI was found to be 492.7 nm and that of uncapped CuI was found to be 2.96 µm using HR-SEM analysis. The crystals obtained were further characterized using EDAX, FTIR spectroscopy and UV-Visible spectroscopy. Antibacterial activity of prismatic CuI capped with the flower extract of Hibiscus rosa-sinensis showed better activity than that of uncapped CuI. AFM analysis was carried out to confirm the proposed mechanism for antibacterial activity through the morphological changes on the bacterial cell wall in the presence of capped CuI. Molecular docking studies were performed to reaffirm the enhanced antibacterial activity of prismatic CuI further. The present study demonstrates the superior antibacterial propensity of prismatic CuI, consequently making it a potent antibacterial agent.


Assuntos
Antocianinas , Antibacterianos , Antocianinas/farmacologia , Antibacterianos/farmacologia , Cobre , Simulação de Acoplamento Molecular , Espectroscopia de Infravermelho com Transformada de Fourier
10.
J Biomol Struct Dyn ; 39(5): 1795-1810, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32186243

RESUMO

Krabbe disease (KD), also known as globoid cell leukodystrophy disease, is an autosomal recessive lysosomal storage genetic disorder, which is caused by the deficiency of galactocerebrosidase (GALC) coding gene (GALC). This study aimed to use extensive computational pipelines in understanding the missense mutations in GALC. We retrieved 176 mutations from the public databases and subjected them to pathogenicity, stability, and conservation analyses. The PredictSNP, iStable, and ConSurf prediction tools predicted 45, 95, and 47 mutations to be deleterious, destabilizing, and highly conserved, respectively. The R396L and R396W were the most deleterious and destabilizing to GALC, and were therefore prioritized for further analysis. Systematic validation on the impact of the R396L and R396W mutations to the chaperone alpha lobeline was performed using the molecular docking approach. The docking analysis revealed that the mutant R396W interacted with minimal binding affinity compared with both the R396L mutant and native GALC. Furthermore, the repetitive molecular dynamics simulation analysis showed that the mutant R396W demonstrated less compactness and reduced number of intramolecular hydrogen bonds compared with the mutant R396L and the native GALC. Overall, we observed higher structural and functional modifications in R396W positioned in the substrate-binding site. This was highly supported by the MMPBSA and DSSP analysis of the GROMACS. DSSP showed the transformation of turns to bends, indicating a loss of stability due to the R396W mutation. This study is expected to serve as a platform for prioritizing mutant proteins that could be a platform for both drug and target therapeuticsCommunicated by Ramaswamy H. Sarma.


Assuntos
Galactosilceramidase , Leucodistrofia de Células Globoides , Galactosilceramidase/genética , Galactosilceramidase/metabolismo , Humanos , Leucodistrofia de Células Globoides/genética , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Mutação de Sentido Incorreto
11.
J Cell Biochem ; 119(9): 7585-7598, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29893426

RESUMO

Galactosemia type 2 is an autosomal recessive disorder characterized by the deficiency of galactokinase (GALK) enzyme due to missense mutations in GALK1 gene, which is associated with various manifestations such as hyper galactosemia and formation of cataracts. GALK enzyme catalyzes the adenosine triphosphate (ATP)-dependent phosphorylation of α-d-galactose to galactose-1-phosphate. We searched 4 different literature databases (Google Scholar, PubMed, PubMed Central, and Science Direct) and 3 gene-variant databases (Online Mendelian Inheritance in Man, Human Gene Mutation Database, and UniProt) to collect all the reported missense mutations associated with GALK deficiency. Our search strategy yielded 32 missense mutations. We used several computational tools (pathogenicity and stability, biophysical characterization, and physiochemical analyses) to prioritize the most significant mutations for further analyses. On the basis of the pathogenicity and stability predictions, 3 mutations (P28T, A198V, and L139P) were chosen to be tested further for physicochemical characterization, molecular docking, and simulation analyses. Molecular docking analysis revealed a decrease in interaction between the protein and ATP in all the 3 mutations, and molecular dynamic simulations of 50 ns showed a loss of stability and compactness in the mutant proteins. As the next step, comparative physicochemical changes of the native and the mutant proteins were carried out using essential dynamics. Overall, P28T and A198V were predicted to alter the structure and function of GALK protein when compared to the mutant L139P. This study demonstrates the power of computational analysis in variant classification and interpretation and provides a platform for developing targeted therapeutics.


Assuntos
Galactoquinase/genética , Galactosemias/genética , Simulação de Acoplamento Molecular , Mutação de Sentido Incorreto , Trifosfato de Adenosina/metabolismo , Galactoquinase/metabolismo , Galactosemias/metabolismo , Humanos , Ligação Proteica , Conformação Proteica
12.
Int J Biol Macromol ; 107(Pt B): 1675-1682, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29054523

RESUMO

The glandular hair extracts from the fruit rind of Mallotus philippinensis Muell. is employed to treat various skin infections, however the anti-tyrosinase activity remains unknown. Hence the present study inspected on the anti-melanogenic activity of M. philippinensis constituents. Lineweaver Burk plot revealed mixed inhibition for Rottlerin; non-competitive type of inhibition for mallotophilippen A and B respectively. Thermodynamic studies resulted in static quenching forming ground state complex with higher binding constant temperature dependently. Fluorescence and circular dichroism study implicated conformational change in secondary and tertiary structure of tyrosinase. Molecular docking suggests rottlerin has high binding affinity to the active site pocket of tyrosinase. Simulation study further proved that the compactness of inhibitor with tyrosinase by hydrogen bonding influenced the stability of the enzyme. Depigmentation efficacy is further proved in Aspergillus niger spores. Thus our findings delineate that rottlerin could be utilized as a depigmentation agent in food pharmaceutical and agricultural industries.


Assuntos
Inibidores Enzimáticos/farmacologia , Frutas/química , Mallotus (Planta)/anatomia & histologia , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores , Aspergillus niger/efeitos dos fármacos , Dicroísmo Circular , Ensaios Enzimáticos , Inibidores Enzimáticos/química , Cinética , Simulação de Dinâmica Molecular , Monofenol Mono-Oxigenase/química , Fenótipo , Estrutura Secundária de Proteína , Espectrometria de Fluorescência , Esporos Fúngicos/efeitos dos fármacos , Termodinâmica
13.
Hum Mol Genet ; 26(16): 3105-3115, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28535199

RESUMO

Isovaleric acidaemia (IVA) is an autosomal recessive inborn error of leucine metabolism. It is caused by a deficiency in the mitochondrial isovaleryl-CoA dehydrogenase (IVD) enzyme. In this study, we investigated eight patients with IVA. The patients' diagnoses were confirmed by urinary organic acid analysis and the blood C5-Carnitine value. A molecular genetic analysis of the IVD gene revealed nine different variants: five were missense variants (c.1193G > A; p. R398Q, c.1207T > A; p. Y403N, c.872C > T; p. A291V, c.749G > C; p. G250A, c.1136T > C; p.I379T), one was a frameshift variant (c.ins386 T; p. Y129fs), one was a splicing variant (c.465 + 2T > C), one was a polymorphism (c.732C > T; p. D244D), and one was an intronic benign variant (c.287 + 14T > C). Interestingly, all variants were in homozygous form, and four variants were novel (p. Y403N, p. Y129fs, p. A291V, p. G250A) and absent from 200 normal chromosomes. We performed protein modelling and dynamics analyses, pathogenicity and stability analyses, and a physiochemical properties analysis of the five missense variants (p.Y403N, R398Q, p.A291V, p.G250A, and p.I379T). Variants p.I379T and p.R398Q were found to be the most deleterious and destabilizing compared to variants p.A291V and p.Y403N. However, the four variants were predicted to be severe by the protein dynamic and in silico analysis, which was consistent with the patients' clinical phenotypes. The p.G250A variant was computationally predicted as mild, which was consistent with the severity of the clinical phenotype. This study reveals a potentially meaningful genotype-phenotype correlation for our patient cohort and highlights the development and use of this computational analysis for future assessments of genetic variants in the clinic.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/genética , Isovaleril-CoA Desidrogenase/deficiência , Isovaleril-CoA Desidrogenase/genética , Sequência de Bases , Carnitina/sangue , Criança , Pré-Escolar , Éxons/genética , Feminino , Estudos de Associação Genética/métodos , Humanos , Lactente , Íntrons/genética , Isovaleril-CoA Desidrogenase/metabolismo , Masculino , Mutação , Polimorfismo Genético/genética , Splicing de RNA/genética
14.
J Biomol Struct Dyn ; 34(1): 29-41, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25679319

RESUMO

We examined 25 breast tumor samples for somatic mutations in exon 20 and exon 9 of PIK3CA gene in South Indian population. Genomic DNA was isolated and amplified for PIK3CA gene, followed by direct sequencing of purified polymerase chain reaction products. We identified PI3K3CA mutations in 5 of 25 (20%), including four of the mutations in p.H1047R and one in p.H1047L. Nucleotide base substitution A to G (c.3140A > G) and A to T (c.3140A > T) results in p.H1047R and p.H1047L mutation in exon 20 of PIK3CA gene. We did not observe any mutation in exon 9 of PIK3CA gene. Furthermore, we investigated the effect of mutations on protein structure and function by the combination of sequence and structure-based in silico prediction methods. This determined the underlying relationship between the mutation and its phenotypic effects. Next step, we complemented by molecular dynamics simulation analysis (30 ns) of native and mutant structures that measured the effect of mutation on protein structure. The obtained results support that the application of computational methods helps predict the biological significance of mutations.


Assuntos
Neoplasias da Mama/genética , Simulação de Dinâmica Molecular , Fosfatidilinositol 3-Quinases/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Classe I de Fosfatidilinositol 3-Quinases , Éxons/genética , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Pessoa de Meia-Idade , Mutação , Fosfatidilinositol 3-Quinases/química , Conformação Proteica , Relação Estrutura-Atividade
15.
Biomed Res Int ; 2014: 327950, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25126554

RESUMO

Proteins and genes of therapeutic interests in conjunction with different delivery systems are growing towards new heights. "Next generation delivery systems" may provide more efficient platform for delivery of proteins and genes. In the present review, snapshots about the benefits of proteins or gene therapy, general procedures for therapeutic protein or gene delivery system, and different next generation delivery system such as liposome, PEGylation, HESylation, and nanoparticle based delivery have been depicted with their detailed explanation.


Assuntos
Sistemas de Liberação de Medicamentos , Técnicas de Transferência de Genes , Terapia Genética , Proteínas/uso terapêutico , Humanos , Lipossomos/química , Lipossomos/uso terapêutico , Nanopartículas/química , Nanopartículas/uso terapêutico , Proteínas/genética
16.
Appl Biochem Biotechnol ; 172(3): 1265-81, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24158589

RESUMO

Excision repair cross complementation group 1 (ERCC1) is an important protein in the nucleotide excision repair (NER) pathway, which is responsible for removing DNA adducts induced by platinum based compounds. The heterodimer ERCC1-XPF is one of two endonucleases required for NER. Genetic variations or polymorphisms in ERCC1 gene alter DNA repair capacity. Reduced DNA repair (NER) capacity may result in tumors and enhances cisplatin chemotherapy in cancer patients, which functions by causing DNA damage. Therefore, ERCC1 variants have the potential to be used as a strong candidate biomarker in cancer treatments. In this study we identified five variants V116M, R156Q, A199T, S267P, and R322C of ERCC1 gene as highly deleterious. Further structural and functional analysis has been conducted for ERCC1 protein in the presence of three variants V116M, R156Q, and A199T. Occurrence of theses variations adversely affected the regular interaction between ERCC1 and XPF protein. Analysis of 20 ns molecular dynamics simulation trajectories reveals that the predicted deleterious variants altered the ERCC1-XPF complex stability, flexibility, and surface area. Notably, the number of hydrogen bonds in ERCC1-XPF mutant complexes decreased in the molecular dynamic simulation periods. Overall, this study explores the link between the ERCC1 deleterious variants and cisplatin chemotherapy for various cancers with the help of molecular docking and molecular dynamic approaches.


Assuntos
Reparo do DNA/genética , Proteínas de Ligação a DNA , Endonucleases , Neoplasias/genética , Relação Estrutura-Atividade , Animais , Células CHO , Cisplatino/administração & dosagem , Cricetinae , Cricetulus , Dano ao DNA/genética , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Endonucleases/química , Endonucleases/genética , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Neoplasias/tratamento farmacológico , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , Deleção de Sequência
17.
J Carcinog ; 10: 26, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22190868

RESUMO

BACKGROUND: Distinguishing the deleterious from the massive number of non-functional nsSNPs that occur within a single genome is a considerable challenge in mutation research. In this approach, we have used the existing in silico methods to explore the mutation-structure-function relationship in the XPAgene. MATERIALS AND METHODS: We used the Sorting Intolerant From Tolerant (SIFT), Polymorphism Phenotyping (PolyPhen), I-Mutant 2.0, and the Protein Analysis THrough Evolutionary Relationships methods to predict the effects of deleterious nsSNPs on protein function and evaluated the impact of mutation on protein stability by Molecular Dynamics simulations. RESULTS: By comparing the scores of all the four in silico methods, nsSNP with an ID rs104894131 at position C108F was predicted to be highly deleterious. We extended our Molecular dynamics approach to gain insight into the impact of this non-synonymous polymorphism on structural changes that may affect the activity of the XPAgene. CONCLUSION: Based on the in silico methods score, potential energy, root-mean-square deviation, and root-mean-square fluctuation, we predict that deleterious nsSNP at position C108F would play a significant role in causing disease by the XPA gene. Our approach would present the application of in silicotools in understanding the functional variation from the perspective of structure, evolution, and phenotype.

18.
C R Biol ; 331(7): 489-99, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18558372

RESUMO

Dopamine receptors play a critical role in the cell signalling process responsible for information transfer in neurons functioning in the nervous system. Development of improved therapeutics for disorders like Parkinson's disease and schizophrenia would be significantly enhanced with the availability of the 3D structure for the dopamine receptors. Scorpion neurotoxins are unique source of structural templates from which new therapeutic agents might be developed. We report here the 3D structure of the human D1 dopamine receptor, predicted from primary sequence using computational techniques. The predicted structure of the human D1 dopamine receptor is used to understand the mechanism of interactions between scorpion neurotoxins through the protein-protein docking method. CHARMM force field was used for the energy minimization step before applying the docking method.


Assuntos
Charibdotoxina/farmacologia , Neurotoxinas/farmacologia , Receptores de Dopamina D1/fisiologia , Venenos de Escorpião/farmacologia , Sequência de Aminoácidos , Calorimetria , Biologia Computacional , Estabilidade de Medicamentos , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Receptores de Dopamina D1/química , Receptores de Dopamina D1/efeitos dos fármacos , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Termodinâmica
19.
Biochimie ; 90(10): 1523-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18573309

RESUMO

In this study, we identified the most deleterious nsSNP in CDKN2A gene through structural and functional properties of its protein (p16INK4A) and investigated its binding affinity with cdk6. Out of 118 SNPs, 14 are nsSNPs in the coding region and 17 SNPs were found in the untranslated region (UTR). FastSNP suggested that 7 SNPs in the 5' UTR might change the protein expression levels. Sixty-four percent of nsSNPs are found to be damaged in PolyPhen server among the 14 nsSNPs investigated. With this effort, we modeled the mutant p16INK4A proteins based on these deleterious nsSNPs, out of which three nsSNPs associated p16INK4A had RMSD values of greater than 3.00 A with native protein. From a comparison of total energy of these three mutant proteins, we identified that the major mutation is from Aspartic acid to Tyrosine at the residue position of 84 of p16INK4A. Further, we compared the binding efficiency of both native and mutant p16INK4A with cdk6. We found that mutant p16INK4A has less binding affinity with cdk6 compared to native type. This is due to ten hydrogen bonds and eight salt bridges which exist between the native type and cdk6, whereas the mutant type makes only nine hydrogen bonds and five salt bridges with cdk6. Based on our investigation, we propose that the SNP with the ID rs11552822 could be the most deleterious nsSNP in CDKN2A gene, causing malignant melanoma, as it was well correlated with experimental studies carried out elsewhere.


Assuntos
Biologia Computacional , Inibidor p16 de Quinase Dependente de Ciclina/química , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Genes p16 , Melanoma/genética , Modelos Biológicos , Polimorfismo de Nucleotídeo Único , Inibidor p16 de Quinase Dependente de Ciclina/genética , Bases de Dados Genéticas , Modelos Moleculares , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Ligação Proteica , Conformação Proteica , Software , Regiões não Traduzidas
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