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1.
J Biochem Mol Toxicol ; 35(10): e22864, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34309121

RESUMO

The retrograde signaling pathway is well conserved from yeast to humans, which regulates cell adaptation during stress conditions and prevents cell death. One of its components, RTG1 encoded Rtg1p in association with Rtg3p communicates between mitochondria, nucleus, and peroxisome during stress for adaptation, by regulation of transcription. The F-box motif protein encoded by YDR131C  constitutes a part of SCF Ydr131c -E3 ligase complex, with unknown function; however, it is known that retrograde signaling is modulated by the E3 ligase complex. This study reports epistasis interaction between YDR131C and RTG1, which regulates cell growth, response to genotoxic stress, decreased apoptosis, resistance to petite mutation, and cell wall integrity. The cells of ydr131cΔrtg1Δ genetic background exhibits growth rate improvement however, sensitivity to hydroxyurea, itraconazole antifungal agent and synthetic indoloquinazoline-based alkaloid (8-fluorotryptanthrin, RK64), which disrupts the cell wall integrity in Saccharomyces cerevisiae. The epistatic interaction between YDR131C and RTG1 indicates a link between protein degradation and retrograde signaling pathways.


Assuntos
Apoptose/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Dano ao DNA/genética , Epistasia Genética , Motivos F-Box/genética , Regulação Fúngica da Expressão Gênica , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Transdução de Sinais/genética , Ácido Acético/farmacologia , Antifúngicos/farmacologia , Apoptose/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Crescimento Celular/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Etídio/farmacologia , Deleção de Genes , Peróxido de Hidrogênio/farmacologia , Hidroxiureia/farmacologia , Itraconazol/farmacologia , Microrganismos Geneticamente Modificados , Mutação/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Ácidos Sulfínicos/farmacologia
2.
Sci Rep ; 13(1): 7852, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37188759

RESUMO

Neurofibromatosis type 1 (NF1) is a multisystemic hereditary disorder associated with an increased risk of benign and malignant tumor formation predominantly on the skin, bone, and peripheral nervous system. It has been reported that out of all the NF1 cases, more than 95% cases develop the disease due to heterozygous loss-of-function variants in Neurofibromin (NF1) gene. However, identification of NF1 causative variants by presently recommended method of gene-targeted Sanger sequencing is challenging and cost-intensive due to the large size of the NF1gene with 60 exons spanning about 350 kb. Further, conducting the genetic studies is difficult in low resource regions and among families with the limited financial capabilities, restricting them from availing diagnostic as well as proper disease management measures. Here, we studied a three-generation family from Jammu and Kashmir state in India, with multiple affected family members showing clinical indications of NF1. We combinedly used two applications, Whole Exome Sequencing (WES) and Sanger sequencing, for this study and discovered a nonsense variant NM_000267.3:c.2041C>T (NP_000258.1:p.Arg681Ter*) in exon 18 of NF1 gene in a cost effective manner. In silico analyses further substantiated the pathogenicity of this novel variant. The study also emphasized on the role of Next Generation Sequencing (NGS) as a cost-effective method for the discovery of pathogenic variants in disorders with known phenotypes found in large sized candidate genes. The current study is the first study based on the genetic characterization of NF1 from Jammu and Kashmir-India, highlighting the importance of the described methodology adopted for the identification and understanding of the disease in low resource region. The early diagnosis of genetic disorders would open the door to appropriate genetic counseling, reducing the disease burden in the affected families and the general population at large.


Assuntos
Neurofibromatose 1 , Humanos , Neurofibromatose 1/diagnóstico , Neurofibromatose 1/genética , Neurofibromatose 1/patologia , Mutação , Sequenciamento do Exoma , Análise Custo-Benefício , Linhagem , Índia
3.
Amino Acids ; 42(4): 1349-60, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21229277

RESUMO

Multiple different approaches are being used to activate the immune system against breast cancer. Vaccine therapy in general follows the principle that injections of various substances ultimately result in the presentation of tumor peptides to the patient's immune system. We proposed a potential in silico DNA vaccine against breast cancer by integrating high affinity T cell (MHC-I and MHC-II) and B cell (continuous and discontinuous) epitopes. The matching of the HLA haplotype and antigen was performed to provide the appropriate peptide epitope suitable for majority of the patients. The immunogenic nature of the antigenic construct was also enhanced by the administration of consensus epitopes. The potency of DNA vaccines depends on the efficient expression and presentation of the encoded antigen of interest and the chances of efficient expression of our antigenic construct in host organism was also verified by in silico approaches. An attempt was made to overcome the limited potency of the DNA vaccine by targeting DNA to professional antigen-presenting cells (APCs). A higher immune response theoretically corresponds to a higher survival rate of patients. Therefore, optimization studies were also employed to enhance the immunogenicity of proposed in silico DNA vaccine.


Assuntos
Neoplasias da Mama/prevenção & controle , Vacinas Anticâncer/química , Epitopos de Linfócito B/química , Epitopos de Linfócito T/química , Proteômica/métodos , Receptor ErbB-2/química , Sequência de Aminoácidos , Neoplasias da Mama/imunologia , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Mapeamento de Epitopos , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Feminino , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Proteômica/instrumentação , Receptor ErbB-2/genética , Receptor ErbB-2/imunologia , Vacinas de DNA/química , Vacinas de DNA/genética , Vacinas de DNA/imunologia
4.
Microb Pathog ; 51(1-2): 77-87, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21349321

RESUMO

African trypanosomiasis continues to be a major health problem, with more adults dying from this disease world-wide. As the sequence diversity of Trypanosoma brucei is extreme, with VSGs having 15-25% identity with most other VSGs, hence it displays a huge diversity of adaptations and host specificities. Therefore the need for an improved vaccine has become an international priority. The highly conserved and specific epitopes acting as both CD8+ and CD4+ T-cell epitopes (FLINKKPAL and FTALCTLAA) were predicted from large bunch of VSGs of T. brucei. Besides, some other potential epitopes with very high affinity for MHC I and II molecules were also determined while taking consideration on the most common HLA in the general population which accounts for major ethnicities. The vaccine candidates were found to be effective even for non-african populations as predicted by population coverage analysis. Hence the migrating travelers acting as a spread means of the infection can probably also be treated successfully after injection of such a multiepitopic vaccine. Exploiting the immunoinformatics approaches, we designed a potential vaccine by using the consensus epitopic sequence of 388 VSG proteins of T. brucei and performed in silico cloning of multiepitopic antigenic DNA sequence in pBI-CMV1 vector. Moreover, various techniques like codon adaptation, CpG optimization, removal of self recognized epitopes, use of adjuvant and co-injection with plasmids expressing immune-stimulatory molecules were implemented to enhance the immunogenicity of the proposed in silico vaccine.


Assuntos
Desenho de Fármacos , Epitopos de Linfócito T/imunologia , Interleucina-12/imunologia , Vacinas Protozoárias/imunologia , Trypanosoma brucei brucei/imunologia , Vacinas de DNA/imunologia , Glicoproteínas Variantes de Superfície de Trypanosoma/imunologia , Adjuvantes Imunológicos , Sequência de Aminoácidos , Animais , Variação Antigênica , Epitopos de Linfócito T/química , Epitopos de Linfócito T/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Interleucina-12/genética , Interleucina-12/metabolismo , Dados de Sequência Molecular , Vacinas Protozoárias/genética , Trypanosoma brucei brucei/genética , Trypanosoma brucei brucei/metabolismo , Tripanossomíase Africana/imunologia , Tripanossomíase Africana/parasitologia , Tripanossomíase Africana/prevenção & controle , Glicoproteínas Variantes de Superfície de Trypanosoma/química , Glicoproteínas Variantes de Superfície de Trypanosoma/genética , Glicoproteínas Variantes de Superfície de Trypanosoma/metabolismo
5.
Int J Gynaecol Obstet ; 148(1): 118-122, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31605628

RESUMO

OBJECTIVE: To investigate the association of newly identified genetic variants G>A (rs2285947) of the DNAH11 gene and G>A (rs2494938) of the LRFN2 gene with ovarian and breast cancers in women belonging to Jammu and Kashmir state, where the prevalence of ovarian and breast cancers is remarkably high in the population. METHODS: A candidate gene prospective case-control association study design was adopted, in which 354 cases (219 cases of ovarian cancer and 135 cases of breast cancer) were histopathologically confirmed and 330 healthy controls matched for age and ethnicity were recruited. The details of cases and controls were also recorded in a predesigned pro forma after their written informed consent. Both variants were genotyped by TaqMan allele discrimination assay using real-time polymerase chain reaction. Logistic regression analysis was performed to estimate the corrected odds ratio (OR), confidence interval (CI), and level of significance (P value) for potential confounding factors. RESULTS: The rs2285947 variant of DNAH11 was found to be significantly associated with both ovarian and breast cancers with adjusted ORs of 1.7 (95% CI 1.2-2.4; P=0.004) and 1.70 (95% CI 1.13-2.54; P=0.0009), respectively. However, no significant association of variant rs2494938 of LRFN2 was observed with ovarian cancer (estimated OR 0.9, 95% CI 0.6-1.4; P=0.919) or breast cancer (estimated OR 1.27, 95% CI 0.8-1.9; P=0.216). CONCLUSIONS: The collected data proposed that the variant rs2285947 of DNAH11 gene is a potential risk factor for ovarian and breast cancers in the studied population.


Assuntos
Dineínas do Axonema , Neoplasias da Mama/genética , Predisposição Genética para Doença , Glicoproteínas de Membrana , Proteínas do Tecido Nervoso , Neoplasias Ovarianas/genética , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco
6.
Front Genet ; 11: 415, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32425985

RESUMO

Rare diseases (RDs) are the clinical conditions affecting a few percentage of individuals in a general population compared to other diseases. Limited clinical information and a lack of reliable epidemiological data make their timely diagnosis and therapeutic management difficult. Emerging Next-Generation DNA Sequencing technologies have enhanced our horizons on patho-physiological understanding of many of the RDs and ushered us into an era of diagnostic and therapeutic research related to this ignored health challenge. Unfortunately, relevant research is meager in developing countries which lack a reliable estimate of the exact burden of most of the RDs. India is to be considered as the "Pandora's Box of genetic disorders." Owing to its huge population heterogeneity and high inbreeding or endogamy rates, a higher burden of rare recessive genetic diseases is expected and supported by the literature findings that endogamy is highly detrimental to health as it enhances the degree of homozygosity of recessive alleles in the general population. The population of a low resource region Jammu and Kashmir (J&K) - India, is highly inbred. Some of its population groups variably practice consanguinity. In context with the region's typical geographical topography, highly inbred population structure and unique but heterogeneous gene pool, a huge burden of known and uncharacterized genetic disorders is expected. Unfortunately, many suspected cases of genetic disorders remain undiagnosed or misdiagnosed due to lack of appropriate clinical as well as diagnostic resources in the region, causing patients to face a huge psycho-socio-economic crisis and many a time suffer life-long with their ailment. In this review, the major challenges associated with RDs are highlighted in general and an account on the methods that can be adopted for conducting fruitful molecular genetic studies in genetically vulnerable and low resource regions is also provided, with an example of a region like J&K - India.

7.
J Gen Appl Microbiol ; 55(5): 317-21, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19940376

RESUMO

We have recently reported the purification and characterization of a novel esterase from the Bacillus subtilis strain. In the present study we report the genomic DNA cloning and predictive structural modeling of this novel esterase. Tributyrin- and Rhodamine B-based functional screen of a Bacillus subtilis genomic library led to the identification of a potential lipolytic gene. DNA sequence analysis of the cloned gene showed that it encodes a protein of 489 amino acid residues. Sequence homology search and multiple sequence alignment showed that the protein was highly homologous to known esterases. Secondary structure-driven multiple sequence alignment with the homologous esterase of known three-dimensional structures was performed and a 3D structure model of this enzyme was constructed. Based on the topological organization of the secondary structures, this protein belongs to the alpha/beta hydrolase superfamily. Moreover, the presence of serine in the context of amino acid sequence G/A-X-S-X-G (with X an arbitrary amino acid residue) in the protein indicates that it belong to the class of serine hydrolases of this superfamily.


Assuntos
Bacillus subtilis/genética , Esterases/genética , Regulação Bacteriana da Expressão Gênica , Sequência de Aminoácidos , Bacillus subtilis/enzimologia , Bacillus subtilis/metabolismo , Proteínas de Bactérias , Clonagem Molecular , DNA Bacteriano/química , Esterases/metabolismo , Teste de Complementação Genética , Modelos Moleculares , Dados de Sequência Molecular , RNA Bacteriano/análise , Alinhamento de Sequência
8.
J Dairy Res ; 76(2): 188-94, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19281632

RESUMO

A multiplex PCR (mPCR) assay using previously known genetic markers of Shigella, Escherichia coli and Shiga-toxic Esch. coli was standardized. uidA gene was targeted for the common detection of Esch. coli and Shigella, whereas ipaH and stx1 genes were used as markers for the detection of Shigella and shiga-toxin producing strains, respectively. The standardized assays detected the target organism specifically and selectively. The mPCR developed by combining all the three reactions generated specific products. The inclusivity and exclusivity tests depicted the precise specificity of the mPCR assay. Results were interpreted on the basis of the pattern of amplicons generated: amplifications of the ipaH and uidA gene fragments indicated the presence of Shigella spp., amplification of uidA alone revealed the presence of Esch. coli and additional presence of verotoxin gene amplicon indicated verotoxinogenic nature of the strain. Specific patterns of bands were obtained when different strains of Esch. coli and Shigella spp. were subjected to this assay. The reactions, individually as well as in the mPCR, could detect approximately 1 cell per 20-microl PCR assay. The protocols were validated by analyzing the coded samples of full fat milk spiked with different pathogens. In naturally contaminated raw milk samples (n=100), Esch. coli were detected in all samples and verotoxinogenic Esch. coli in 15 samples. Shigella, however, was not detected in any of the samples. When DNA purified from the samples found positive for Shiga-toxic Esch. coli was directly used as template for the mPCR, the results showed agreement with the enrichment based detection. The mPCR assay, standardized in this study, may be used for rapid microbiological evaluation of milk samples. Further, the study emphasizes the need for better hygienic conditions in dairies.


Assuntos
Escherichia coli/isolamento & purificação , Leite/microbiologia , Reação em Cadeia da Polimerase/métodos , Toxinas Shiga/metabolismo , Shigella/isolamento & purificação , Animais , Bovinos , Escherichia coli/classificação , Escherichia coli/genética , Escherichia coli/metabolismo , Marcadores Genéticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Shigella/genética
9.
3 Biotech ; 9(3): 107, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30863691

RESUMO

Screening of 20,000 clones of a fosmid gene bank, constructed from DNA extracted from North West Himalaya (NWH) glacier soil sample, using functional approach identified 10 esterase/lipase-producing clones. Of these, a clone designated pFG43 with an insert size of 45 kb which produced the highest concentration of enzyme (467.43 U/mg) was sequenced. Clone pFG43 contained 61 open reading frames (ORF) and of these an ORF of 1155 bp designated ME-003, was found to be closely related to a hydrolase from Acidobacteria sps (77% sequence identity and E value = 1e-164) and subsequently identified as a putative cocaine esterase. ORF ME-003 was amplified and sub-cloned using a TA vector system into E. coli (DH5α). The purified recombinant enzyme with a molecular weight of 43 kDa had optimal activity at 40 °C, pH 6 and the highest activity with shorter chain fatty acids than with higher chain length fatty acids. There is insignificant effect of inhibitors on the enzyme activity of ME-003, except PMSF which completely inhibited its activity. ME-003 activity was also inhibited in the presence of copper oxide but remained stable in presence of other metal ions. The enzyme activity was also inhibited in the presence of organic solvents; however, in the presence of 10% isopropanol, 12% of enzymatic activity was retained. Among various detergents, SDS completely inhibited enzymatic activity. The recombinant enzyme also shows enantio-specific activity against the racemic drug intermediates/precursors and exhibited 90% ee against racemic 1-phenyl ethanol and fluoxetine.

10.
Interdiscip Sci ; 11(3): 437-443, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29103184

RESUMO

Many aggressive and metastatic cancer cell types show Warburg Effect; therefore, it is a possible adaptation helping cancer cells to rapidly divide and utilize the glycolytic intermediates for biosynthesis of ribose sugars (for nucleotide biosynthesis), fatty acid synthesis (lipids for membrane synthesis), NADPH (cellular currency for reductive biosynthesis) and lactate. This in due course results in decrease of extracellular pH, leading to acidic tumor micro-environment. EGFR is a crucial cell surface signaling receptor implicated in cancer cell survival and progression. This warrants studying the effect of the acidic micro-environmental conditions on the binding of the EGFR cell surface receptor to one of its natural extracellular ligand EGF. We exploited in silico approaches: molecular dynamics simulation at variable pH and MM-GBSA free energy of binding calculation method to evaluate the effect of this change in microenvironmental pH. Through the present study it is reported that at pH 6.6 the EGFR binds to EGF with decreased free energy of binding as compared to pH 7.2.


Assuntos
Simulação de Dinâmica Molecular , Neoplasias/genética , Membrana Celular/metabolismo , Receptores ErbB/química , Glicólise , Humanos , Concentração de Íons de Hidrogênio , Ligantes , Lipídeos/química , Domínios Proteicos , Termodinâmica , Microambiente Tumoral
11.
J Biomol Struct Dyn ; 37(16): 4361-4373, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30466358

RESUMO

The prevailing multi-drug resistance in Mycobacterium tuberculosis continues to remain one of the main challenges to combat tuberculosis. Hence, it becomes imperative to focus on novel drug targets. Filamenting temperature-sensitive mutant Z (FtsZ) is an essential cell division protein, a eukaryotic tubulin homologue and a promising drug target. During cytokinesis, FtsZ polymerises in the presence of GTP to form Z-ring and recruits other proteins at this site that eventually lead to the formation of daughter cells. Benzimidazoles were experimentally shown to inhibit Mtb-FtsZ, with one of the benzimidazole derivatives, M1, being reported to have the minimum inhibitory concentration (MIC) value of 3.13 µg/mL. In the present study, mechanism of destabilisation of FtsZ in the presence of M1 was computationally investigated in the presence of its substrate GTP/GDP employing molecular dynamics (MD) simulation analysis, principal component analysis (PCA), molecular mechanics combined with the generalised Born and surface area continuum salvation (MM-GBSA) and density functional theory (DFT). From the analyses, it is proposed that binding of M1 in the inter-domain cleft induces structural changes in the GTP-binding region that affect GTP binding, thus switching the preference of this protein towards depolymerised state and eventually inhibiting the cell division. Hence, this study provides mechanistic insights into the design of novel benzimidazole inhibitors against Mtb-FtsZ. Communicated by Ramaswamy H. Sarma.


Assuntos
Proteínas de Bactérias/antagonistas & inibidores , Benzimidazóis/química , Proteínas do Citoesqueleto/antagonistas & inibidores , Guanosina Difosfato/química , Guanosina Trifosfato/química , Mycobacterium tuberculosis/efeitos dos fármacos , Regulação Alostérica , Antituberculosos/farmacologia , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Benzimidazóis/farmacologia , Divisão Celular/efeitos dos fármacos , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/metabolismo , Testes de Sensibilidade Microbiana , Simulação de Dinâmica Molecular , Mycobacterium tuberculosis/metabolismo , Conformação Proteica em alfa-Hélice
12.
J Cancer Res Ther ; 15(6): 1270-1275, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31898659

RESUMO

BACKGROUND: Ovarian cancer is highly prevalent in the population of Jammu, in India; the ovarian cancer ranks third among other types of cancer prevalent in females. However, association studies on ovarian cancer are lacking in this region. We aimed to investigate the disease susceptible variants rs1052133 (human 8-oxoguanine glycosylase 1 [hOGG1]) and rs25487 (X-ray repair cross-complementing 1 [XRCC1]) with ovarian cancer in population of Jammu, India. MATERIALS AND METHODS: The study conducted in the Shri Mata Vaishno Devi University is a 3-year study which included a total of 280 well-characterized samples (130 ovarian cancer cases and 150 healthy controls). hOGG1 and XRCC1 polymorphisms were determined by polymerase chain reaction-based restriction fragment length polymorphism, and these genotyping results were confirmed by Sanger sequencing. Hardy-Weinberg equilibrium for both single-nucleotide polymorphisms (SNPs) was assessed using the Chi-square test. The allele and genotype-specific risks were estimated by odds ratios with 95% confidence intervals. RESULTS: In this preliminary study, SNP rs1052133 showed protection with ovarian cancer (P = 0.042). The SNP rs25487 was not found associated with ovarian cancer (P = 0.271). CONCLUSION: Our results indicate that the G allele of rs1052133 imparts protection to the population whereas variant rs25487 was not associated with ovarian cancer in population from the Jammu region, indicating that larger sample size is needed for further statistical validation. Further, association of other SNPs in these genes should also be carried out as their role cannot be ruled out.


Assuntos
Alelos , DNA Glicosilases/genética , Predisposição Genética para Doença , Variação Genética , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/genética , Proteína 1 Complementadora Cruzada de Reparo de Raio-X/genética , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Humanos , Índia/epidemiologia , Gradação de Tumores , Razão de Chances , Neoplasias Ovarianas/patologia , Vigilância da População , Análise de Sequência de DNA
13.
Food Microbiol ; 25(3): 452-9, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18355670

RESUMO

The aim of this study was to target three genes of Staphylococcus aureus-fmhA (coding for a factor of unknown function), catalase and femA (coding for a factor essential for methicillin resistance) to establish and validate a PCR assay for the detection of this pathogen. Two pairs of primers were designed for fmhA and one pair each for catalase and femA genes. The PCR assays were standardized and found to give specific amplicons under similar reaction parameters. Target specificity of the primers was confirmed by DNA sequencing of the amplicons. While the initial inclusivity and exclusivity test reactions were in agreement in case of three of the primer pairs, one pair based on fmhA gene produced a non-specific product with a template DNA used in exclusivity test reactions. Forty-five strains of S. aureus were subjected to these PCR assays for their evaluation. Three among the four pairs of primers, one against each gene detected all the 45 strains precisely whereas one of the PCR assays using primers targeting the fmhA gene did not generate the specific amplicon with several of the strains. Seven unidentified strains of Gram-positive cocci subjected to these PCR assays produced negative results for each culture. Six of the strains were identified as Staphylococcus haemolyticus and one strain as Staphylococcus arlettae by 16S ribosomal gene analyses. All the three assay systems showed a detection limit of 100 cells per 20mul reaction assay. For validation of these assay systems, 80 coded samples of 11% skimmed milk spiked with different pathogens were received from NICED (National Institute of Cholera and Enteric Diseases), Kolkata and subjected to these PCR assays. All the three assays could detect S. aureus correctly in two of the samples. Amongst 150 raw milk samples, 36 (24%) were found positive for S. aureus. We conclude that fmhA, catalase and femA genes are conserved in S. aureus and, therefore, could be used as specific targets for its detection and identification by PCR. The protocols developed herein could be used for rapid and specific detection of this pathogen in food, clinical and environmental samples, especially milk.


Assuntos
Contaminação de Alimentos/análise , Leite/microbiologia , Reação em Cadeia da Polimerase/métodos , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Animais , Proteínas de Bactérias/genética , Catalase , Primers do DNA , DNA Bacteriano/análise , Marcadores Genéticos , Humanos , Reação em Cadeia da Polimerase/normas , Sensibilidade e Especificidade , Especificidade da Espécie
14.
J Biomol Struct Dyn ; 36(16): 4209-4219, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29183267

RESUMO

Epidermal growth factor receptor kinase is implicated in cancer development due to either overexpression or activation variants in its functional intracellular kinase domain. Threonine to methionine (Thr 790 Met) is one such variant observed commonly in patients showing resistance to kinase inhibitor drug Erlotinib. Two mechanisms for resistance have been proposed (1) steric hindrance and (2) enhanced binding to ATP. In this study, we employed molecular dynamics simulations and studied both the mechanisms. Extensive simulations and free energy of binding analyses has shown that steric hindrance does not explain appropriately the mechanism for resistance against Erlotinib therapy for this variant. It has been observed that conformational switching from an intermediate intrinsically disordered C-helix conformation is required for completion of the kinase's catalytic cycle. Our study substantiates that T790M variant has greater tendency for early transition to this intrinsically disordered C-helix intermediate state. We propose that enhanced catalytic efficiency in addition to enhanced ATP binding explains mechanism of T790M resistance to drug Erlotinib.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Cloridrato de Erlotinib/farmacologia , Variação Genética/genética , Neoplasias/tratamento farmacológico , Neoplasias/genética , Trifosfato de Adenosina/metabolismo , Humanos , Simulação de Dinâmica Molecular , Inibidores de Proteínas Quinases/farmacologia
15.
3 Biotech ; 8(12): 491, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30498664

RESUMO

The present study was conducted to purify lipase from indigenous Bacillus subtilis strain Kakrayal_1 (BSK-L) for enantioselective resolution of racemic-ketoprofen. The production of lipase (BSK-L) was optimized using Plackett-Burman and central composite design of response surface methodology (RSM). The optimized media containing olive oil (3.5%), MnSO4 (8 mM), CaCl2 (5 mM), peptone (20 g/l), pH (8), agitation (180 rpm) and temperature (37 °C) resulted in maximum lipase production of 7500 U/g of cell biomass. The lipase was purified using sequential method to an overall purification fold of 13% with 20% recovery, 882 U/mg specific activity and a molecular weight of 45 kDa. Optimal pH and temperature of purified lipase were found to be 8 and 37 °C, respectively. Furthermore, BSK-L displayed good stability with various organic solvents, surfactants and metal ions. K m and V max values of lipase were observed to be 2.2 mM and 6.67  mmoles of product formed/min/mg, respectively. The racemic ketoprofen butyl ester was hydrolyzed using lipase with 49% conversion efficiency and 69% enantiomeric excess (ee) which was superior to the commercially procured lipase (Candida antarctica lipase). Thus, this enzyme could be considered as a promising candidate for the pharmaceutical industry.

16.
Sci Rep ; 7(1): 4834, 2017 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-28680084

RESUMO

Pantothenate kinase-associated neurodegeneration is a rare hereditary neurodegenerative disorder associated with nucleotide variation(s) in mitochondrial human Pantothenate kinase 2 (hPanK2) protein encoding PANK2 gene, and is characterized by symptoms of extra-pyramidal dysfunction and accumulation of non-heme iron predominantly in the basal ganglia of the brain. In this study, we describe a familial case of PKAN from the State of Jammu and Kashmir (J&K), India based on the clinical findings and genetic screening of two affected siblings born to consanguineous normal parents. The patients present with early-onset, progressive extrapyramidal dysfunction, and brain Magnetic Resonance imaging (MRI) suggestive of symmetrical iron deposition in the globus pallidi. Screening the PANK2 gene in the patients as well as their unaffected family members revealed a functional single nucleotide variation, perfectly segregating in the patient's family in an autosomal recessive mode of inheritance. We also provide the results of in-silico analyses, predicting the functional consequence of the identified PANK2 variant.


Assuntos
Mutação de Sentido Incorreto , Neurodegeneração Associada a Pantotenato-Quinase/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Adulto , Idade de Início , Domínio Catalítico , Simulação por Computador , Consanguinidade , Feminino , Predisposição Genética para Doença , Humanos , Índia , Imageamento por Ressonância Magnética , Masculino , Neurodegeneração Associada a Pantotenato-Quinase/diagnóstico por imagem , Linhagem , Fosfotransferases (Aceptor do Grupo Álcool)/química , Análise de Sequência de DNA/métodos , Adulto Jovem
17.
J Biotechnol ; 125(1): 1-10, 2006 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-16621096

RESUMO

An isolated strain of Bacillus subtilis identified by 16S rDNA sequence analysis produces an enantioselective ester hydrolase. Whole cells of B. subtilis (RRL BB1) and enzyme derived from it was capable of enantioselective hydrolysis of several racemates including drug intermediates with moderate to high enantioselectivity as already reported by us. In this communication, we describe cloning of the gene encoding the enantioselective esterase designated as estBB1. The primary structure of the enzyme determined from the nucleotide sequence indicated that esterase estBB1 has Mw approximately 52kDa and pI approximately 5.2 and belongs to the family of type B carboxylesterases with 50-60% similarity at amino acid level. Alignment studies of sequences of the estBB1 and Pnb esterase 56C8 from B. subtilis showed that estBB1 has an alpha/beta hydrolase fold with catalytic triad formed by Ser190, Glu305 and His394 at active site and Ser190 is located in the conserved motif -G-X-S-X-G-.


Assuntos
Bacillus subtilis/enzimologia , Carboxilesterase/genética , Sequência de Aminoácidos , Bacillus subtilis/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Carboxilesterase/isolamento & purificação , Carboxilesterase/metabolismo , Clonagem Molecular , DNA Bacteriano/química , DNA Bacteriano/genética , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , Hidrólise , Dados de Sequência Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Temperatura , Triglicerídeos/metabolismo
18.
J Biotechnol ; 122(4): 494-510, 2006 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-16375985

RESUMO

The aryl tetralin lignans are synthesized by Podophyllum sps. and are in great demand worldwide due to their use in synthesis of topoisomerase inhibitors. However, the sustained production of these aryl tetralin lignans requires large-scale harvesting from the natural environments, which has resulted in the plant-endangered status. In view of the difficulties in their total chemical synthesis, cultivation and failure of metabolic engineering approaches, there is a need to search for alternative sources of production of aryl tetralin lignans. We unequivocally established the methodology for isolation, identification, and characterization of a novel fungal endophyte (Trametes hirsuta) that produces aryl tetralin lignans consistently as shown by HPLC, LC-MS, LC/MS-MS and (1)H NMR. The lignans produced by the microorganism are biologically active, and exhibit potent antioxidant, anticancer and radioprotective properties. This strategy promises to improve the production of these therapeutically important compounds at lower costs.


Assuntos
Fungos/isolamento & purificação , Lignanas/química , Podofilotoxina/química , Tetra-Hidronaftalenos/química , Fracionamento Celular , Cromatografia Líquida de Alta Pressão , Fungos/citologia , Cinética , Peroxidação de Lipídeos/efeitos da radiação , Modelos Biológicos , Células Vegetais , Estruturas Vegetais/citologia , Estruturas Vegetais/metabolismo , Plantas/metabolismo , Podofilotoxina/metabolismo , Podophyllum/citologia , Podophyllum/metabolismo , Espectrometria de Massas por Ionização por Electrospray
19.
Phytochemistry ; 67(2): 171-7, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16324730

RESUMO

The secondary metabolite contents and genetic profiles of six Hypericum species (H. barbatum Jacq., H. hirsutum L., H. linarioides Bosse, H. maculatum Crantz, H. rumeliacum Boiss. and H. tetrapterum Fries), collected from different locations in Serbia, have been analyzed. Methanol extracts of the aerial parts of the plants were obtained by accelerated solvent extraction (ASE) at 40 degrees C and 100 bar, and analyzed for five pharmacologically important standard constituents (hyperoside, quercitrin, pseudohypericin, hyperforin and hypericin) by LC-MS/MS. The highest content of hypericin and pseudohypericin was observed in the H. barbatum extract, while the highest content of hyperforin and quercitrin was found in the H. tetrapterum extract and the highest content of hyperoside in the H. maculatum extract. A literature survey shows that the above six Hypericum species, with the exception of H. maculatum, have not been previously genetically profiled. In order to correlate the chemical constituents of the species under investigation with their genetic factors, genetic profiling of these species was undertaken using the random amplification of polymorphic DNA (RAPD) and single sequence repeat (SSR) profiles of the above selected plants. Among the 52 random primers used for the initial screening, only 10 yielded polymorphic RAPD profiles. A total of 111 polymorphic markers were generated using these primers. The SSR analysis shows that 8 out of the 10 primers used were polymorphic. The correlation among the species under investigation using the two genetic markers was performed using Jaccuard's coefficients of similarity and a high correlation (r=0.99) was obtained. The main conclusion from the above data is that there exists a stronger correlation for secondary metabolite contents with RAPD data than with SSR data among the six Hypericum species from Serbia.


Assuntos
Hypericum/química , Hypericum/genética , Cromatografia Líquida/métodos , DNA/química , DNA/genética , DNA/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Extratos Vegetais/química , Extratos Vegetais/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Sequências Repetitivas de Ácido Nucleico , Especificidade da Espécie , Iugoslávia
20.
Phytochemistry ; 67(20): 2269-76, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16956635

RESUMO

The main active components and genetic profile of 15 selected accessions of Withania somnifera Dunal. were analysed. Ethanolic extract of the dried roots/leaves of the plant was concentrated under pressure at 50+/-5 degrees C and was analysed for main compounds (withanolides and withaferin A) by HPLC. All the main components were found to be present in accessions (AGB 002, AGB 009, RSS 009, RSS 033). Correlation of these main components with their genetic factors, was undertaken using AFLP (amplified fragment length polymorphism) markers. Among 64 primers 7 yielded optimum polymorphism. A total of 913 polymorphic peaks were generated using these primers. Jaccard's similarity coefficient indicated that accessions having almost the same active compounds clustered together. The present study demonstrates that AFLP can be successfully used to resolve the correlation of AFLP data with the presence of secondary metabolites.


Assuntos
Withania/química , Cromatografia Líquida de Alta Pressão , Impressões Digitais de DNA , Marcadores Genéticos , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/genética , Raízes de Plantas/química , Raízes de Plantas/genética , Polimorfismo Genético , Withania/genética
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