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1.
Proteins ; 90(7): 1425-1433, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35170816

RESUMO

Protein engineering and enzyme immobilization strategies have produced numerous biocatalysts for modern industrial applications. In this study, we have also used these two strategies for improving the operational stability and catalytic efficiency of serine protease from Pseudomonas aeruginosa. The enzyme serine protease was truncated to separate its trypsin-like domain from the PDZ1 and PDZ2 domains. The truncated trypsin-like domain was expressed in Escherichia coli BL21, and its catalytic activity and thermostability were estimated. Later this trypsin-like domain was immobilized with 2% Na-alginate. The immobilized domain showed 10°C increase in optimum temperature compared to its free counterpart. Kinetic studies showed two-folds increased Vmax of the immobilized domain. Likewise, the Km value of this domain was 11.5 folds lower compared to the free trypsin-like domain. The catalytic efficiency (Kcat /Km ) of the immobilized enzyme also elevated to 311 folds. Additionally, the immobilized trypsin-like domain remained active in the presence of surfactants (Triton-X 100, SDS, and Tween-40) and metal ions (Mg2+ , Ca2+ , Na+ , and Zn2+ ). It also efficiently removes gelatin layer from X-ray film and hair from sheepskin. Thus, the immobilized trypsin-like domain of serine protease, with increased thermostability and catalytic efficiency, is operationally more stable than the soluble truncated trypsin-like domain.


Assuntos
Pseudomonas aeruginosa , Serina Proteases , Estabilidade Enzimática , Enzimas Imobilizadas/genética , Enzimas Imobilizadas/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Pseudomonas aeruginosa/metabolismo , Serina Proteases/genética , Serina Proteases/metabolismo , Temperatura , Tripsina/metabolismo
2.
Proteins ; 90(3): 645-657, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34642975

RESUMO

KDM5A over-expression mediates cancer cell proliferation and promotes resistance toward chemotherapy through epigenetic modifications. As its complete mechanism of action is still unknown, there is no KDM5A specific drug available at clinical level. In the current study, lead compounds for KDM5A were determined through pharmacophore modeling and high-throughput virtual screening from Asinex libraries containing 0.5 million compounds. These virtual hits were further evaluated and filtered for ADMET properties. Finally, 726 compounds were used for docking analysis against KDM5A. On the basis of docking score, 10 top-ranked compounds were selected and further evaluated for non-central nervous system (CNS) and CNS drug-like properties. Among these compounds, N-{[(7-Methyl-4-oxo-1,2,3,4-tetrahydrocyclopenta [c] chromen-9-yl) oxy]acetyl}-l-phenylalanine (G-score: -11.363 kcal/mol) was estimated to exhibit non-CNS properties while 2-(3,4-Dimethoxy-phenyl)-7-methoxy-chromen-4-one (G-score: -7.977 kcal/mol) was evaluated as CNS compound. Docked complexes of both compounds were finally selected for molecular dynamic simulation to examine the stability. This study concluded that both these compounds can serve as lead compounds in the quest of finding therapeutic agents against KDM5A associated cancers.


Assuntos
Antineoplásicos/química , Fenilalanina/química , Proteína 2 de Ligação ao Retinoblastoma/metabolismo , Antineoplásicos/farmacologia , Sítios de Ligação , Desenho Assistido por Computador , Ensaios de Seleção de Medicamentos Antitumorais , Ensaios de Triagem em Larga Escala , Ligantes , Simulação de Acoplamento Molecular , Fenilalanina/farmacologia , Ligação Proteica , Relação Estrutura-Atividade , Termodinâmica
3.
J Pak Med Assoc ; 71(9): 2192-2197, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34580513

RESUMO

OBJECTIVE: To assess the significance of serum vascular endothelial growth factor-A (VEGF-A) as a potential biomarker for the diagnosis of ovarian cancer instead of cancer antigen-125 (CA-125). METHODS: The case-control study was conducted at the obstetrics departments of Sir Ganga Ram Hospital and Jinnah Hospital, Lahore, Pakistan, from April to September 2018, and comprised cases of epithelial ovarian tumour and healthy female controls. Serum VEGF-A and CA-125 levels were evaluated using Luminex multi-analyte profiling technology and enzyme immunoassays technique. Age, stage, grading, metastasis and ascites of ovarian cancer patients were investigated and compared with serum VEGF-A and CA-125 levels. Data was analysed using SPSS 20. RESULTS: Of the 89 subjects, 44(49.4%) were cases and 45(49.6%) were controls. Among the cases, 13(29.5%) were benign and 31(70.5%) were malignant. The mean serum VEGF-A values were inversely proportional to the stages of ovarian cancer i.e. stage I, II, III and IV showed 762.2pg/ml, 267.3pg/ml, 233.1pg/ml and 125.5pg/ml VEGF-A levels respectively. A steady increase in the mean serum CA-125 values with the progression of the disease was observed i.e. in stage I, II, III and IV the levels of CA-125 were 146.2U/ml, 268.5U/ml and 477.2U/ml and 844.4U/ml respectively. CONCLUSIONS: The detection of high concentrations of serum VEGF-A level supported its use as one of the diagnostic parameters in the timely investigation of ovarian cancer.


Assuntos
Neoplasias Ovarianas , Fator A de Crescimento do Endotélio Vascular , Biomarcadores Tumorais , Antígeno Ca-125 , Estudos de Casos e Controles , Detecção Precoce de Câncer , Feminino , Humanos , Estadiamento de Neoplasias , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/patologia
4.
Crit Rev Eukaryot Gene Expr ; 30(5): 411-425, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33389878

RESUMO

Pectinase enzymes from different plants have many possible biotechnological applications in various industries. Considering industrial significance of pectinolytic enzymes, the polygalacturonase (PG) gene from grapes was cloned into Escherichia coli DH5α using pTZ57R/T vector. Homologous sequences established a close link to Vitis vinifera. Conserve domain analysis predicted PLN02218 domain belongs to the cl31843 superfamily, showing its function as polygalacturonase. After confirmation by PCR and restriction analysis, the PG gene was expressed in E. coli BL21 and induced by IPTG. Expression level was assessed by 12% SDS-PAGE, which showed a 47 kDa protein. High expression level in the soluble fraction indicated that the protein is intracellular or transmembrane. Maximum expression was obtained with 1 mM IPTG and 6 hour induction time, and autoinduction with lactose increased production of the recombinant enzyme. Zymogram analysis revealed that the induced protein was an active enzyme. Expressed PG showed pectinolytic effect on the physiochemical properties of lemon juice. Natural biopolymers are greatly needed because synthetic fibers can negatively affect health. Pectin hydrolysis of banana pseudostem by the PG enzyme produced better quality fiber. Morphological studies by scanning electron microscopy revealed pectin degradation within the fiber cell architecture, showing the effectiveness of PG treatment on banana pseudostem.


Assuntos
Poligalacturonase/metabolismo , Vitis/enzimologia , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Genes de Plantas , Microscopia Eletrônica de Varredura , Poligalacturonase/genética , Reação em Cadeia da Polimerase , Vitis/genética
5.
Crit Rev Eukaryot Gene Expr ; 29(4): 305-317, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31679292

RESUMO

With the passage of time, energy sources are decreasing day by day. In order to meet the world's demand, much attention is being paid to the study of enzymes with xylanolytic activity as a potential means of generating energy. A thermophilic xylanolytic bacterium, Bacillus sp., was isolated from naturally decaying material by enrichment culture and serial dilution methods. The bacterium was grown in MH medium at 50°C and pH 7 for 10 h. The xylanolytic Bacillus sp. produced clear yellow haloes around the colonies in the presence of p-nitrophenyl beta-D-xylopyranoside (pNPX) as a substrate. After condition optimization, it was found that the organism produced the higher level of xylosidase activity after 14 h in the presence of arabinose as a carbon source and ammonium sulfate as a nitrogen source in the pH 7 medium of at 55°C. The maximum ß-xylosidase activity after optimizing the culture condition was 5.0 U/mL. Later this thermophilic Bacillus sp. was used as a donor in cloning of the ß-xylosidase gene. A genomic library of Bacillus sp. was prepared by digesting the genomic DNA of the Bacillus with the restriction endonuclease BamHI, ligating the fragments in the pUC18 cloning vector and then transforming the competent E. coli DH5α cells with the resultant chimeric plasmid. The ß-xylosidase gene was identified by screening the transformants in duplicates on LB agar plates overlaid with pNPX as a substrate. Commercial production of ß-xylosidase to be used as a methanol-producing enzyme can help to overcome fuel shortages.


Assuntos
Bacillus/enzimologia , Bactérias/enzimologia , Regulação Enzimológica da Expressão Gênica , Proteínas Recombinantes/metabolismo , Xilosidases/metabolismo , Sulfato de Amônio/metabolismo , Arabinose/metabolismo , Bacillus/genética , Bactérias/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Glicosídeos/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Microbiologia Industrial/métodos , Especificidade por Substrato , Temperatura , Transformação Bacteriana , Xilosidases/genética
6.
Mol Biol Rep ; 46(4): 3651-3662, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31079316

RESUMO

Increased demand of enzymes for industrial use has led the scientists towards protein engineering techniques. In different protein engineering strategies, rational approach has emerged as the most efficient method utilizing bioinformatics tools to produce enzymes with desired reaction kinetics; physiochemical (temperature, pH, half life, etc) and biological (selectivity, specificity, etc.) characteristics. Xylanase is one of the widely used enzymes in paper and food industry to degrade xylan component present in plant pulp. In this study endo 1,4-ß-xylanase (Xyl-11A) from Bacillus halodurans C-125 was cloned in pET-22b (+) vector and expressed in Escherichia coli BL21 (DE3) expression strain. The enzyme had Michaelis constant Km of 1.32 mg ml-1 birchwoodxylan (soluble form) and maximum reaction velocity (Vmax) 73.53 mmol min-1 mg-1 with an optimum temperature of 75 °C and pH 9.0. The thermostability analysis showed that enzyme retained more than 80% of its residual activity when incubated at 75 °C for 2 h. In addition, to increase Xyl-11A thermostability, an in-silico analysis was performedto identify the hot spot amino acid residues. Consensus-based amino acid substitution was applied to evaluate multiple sequence alignment of homologs and identified 20 amino acids positions by following Jensen-Shnnon Divergence method. 3D models of 20 selected mutants were analyzed for conformational transition in protein structures by using NMSim server. Two selected mutants T6K and I17M of Xyl-11A retained 40, 60% residual activity respectively, at 85 °C for 120 min as compared to wild type enzyme which retained 37% initial activity under same conditions, confirming the enhanced thermostability of mutants. The present study showed a good approach for the identification of promising amino acid residues responsible for enhancing the thermostability of enzymes of industrial importance.


Assuntos
Bacillus/enzimologia , Endo-1,4-beta-Xilanases/genética , Aminoácidos , Bacillus/genética , Sequência de Bases/genética , Clonagem Molecular , Simulação por Computador , Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/isolamento & purificação , Endo-1,4-beta-Xilanases/metabolismo , Estabilidade Enzimática/genética , Cinética , Modelos Moleculares , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Engenharia de Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Temperatura
7.
Innov Clin Neurosci ; 20(1-3): 60-71, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37122575

RESUMO

Objective: Gene-environment interactions might play a significant role in the development of bipolar disorder (BD). The objective of the current study was to investigate the association between tumor necrosis factor (TNF)-α -308 G/A polymorphism and BD and conduct a bioinformatics analysis of the protein-protein network of TNF-α. Gene-environment interactions and the relationship between stressful life events (SLEs) and substance abuse with TNF genotypes and other characteristics were analyzed. Methods: The genomic deoxyribonucleic acid (DNA) of 400 patients with BD and 200 control subjects were extracted and genotyped for TNF-α -308 G/A polymorphism. SLEs and substance abuse were evaluated using the Life Event and Difficulty Schedule (LEDS) and a self-designed substance abuse questionnaire for the events six months prior to the onset of the disease, respectively. Gene-environment interactions were assessed by multiple statistical tools. Bioinformatics analysis of the TNF-α network and its interacting proteins was carried out using STRING and Cytoscape softwares. Results: Genotyping analysis revealed a significant association between TNF-α -308 G/A polymorphism and BD (p<0.009). Furthermore, analysis of gene-environment interaction revealed a significant association between TNF-α -308 G/A and SLEs (p=0.001) and TNF-α -308 G/A and substance abuse (p=0.001). Three distinct proteins, RELA, RIPK1, and BIRC3, were identified through hub analysis of the protein network. Conclusion: TNF-α -308 G/A polymorphism is positively associated with BD. SLEs and substance abuse might trigger the early onset of BD. Proteins identified through bioinformatics analysis might contribute to the TNF-α mediated pathophysiology of BD and can be the potential therapeutic targets.

8.
J Biomol Struct Dyn ; 41(10): 4641-4649, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35510584

RESUMO

TULP3 is involved in cell regulation pathways including transcription and signal transduction. In some pathological states like in cancers, increased level of TULP3 has been observed so it can serve as a potential target to hamper the activation of those pathways. We propose a novel idea of inhibiting nuclear localization signal (NLS) to interrupt nuclear translocation of TULP3 so that the downstream activations of pathways are blocked. In current in silico study, 3D structure of TULP3 was modeled using 8 different tools including I-TASSER, CABS-FOLD, Phyre2, PSIPRED, RaptorX, Robetta, Rosetta and Prime by Schrödinger. Best structure was selected after quality evaluation by SAVES and implied for the investigation of NLS sequence. Mapped NLS sequence was further used to dock with natural ligand importin-α as control docking to validate the NLS sequence as binding site. After docking and molecular dynamics (MD) simulation validation, these residues were used as binding side for subsequent docking studies. 70 alkaloids were selected after intensive literature survey and were virtually docked with NLS sequence where natural ligand importin-α is supposed to be bound. This study demonstrates the virtual inhibition of NLS sequence so that it paves a way for future in-vivo studies to use NLS as a new drug target for cancer therapeutics.Communicated by Ramaswamy H. Sarma.


Assuntos
Sinais de Localização Nuclear , alfa Carioferinas , Sinais de Localização Nuclear/química , alfa Carioferinas/química , Ligantes , Ligação Proteica , Núcleo Celular/metabolismo , Transporte Ativo do Núcleo Celular
9.
Mol Biotechnol ; 65(7): 1062-1075, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36437440

RESUMO

The current study focuses on molecular cloning, expression and structural characterization of growth hormone-receptor (GHR) and its extracellular domain as growth hormone binding protein (GHBP) from the liver of Nili-Ravi buffalo (Bubalus bubalis; Bb). RNA was isolated, genes were amplified by reverse transcriptase-polymerase chain reaction and sequence was characterized. The BbGHR sequence showed three amino acid variations in the extracellular domain when compared with Indian BbGHR. For the production of full length BbGHR and BbGHBP in Escherichia coli (E. coli) BL21 (RIPL) Codon Plus, expression plasmids were constructed under the control of T7lac promoter and isopropyl ß-D thiogalactopyranoside was used as an inducer. BbGHR and BbGHBP were expressed as inclusion bodies at ~ 40% and > 30% of the total E. coli proteins, respectively. The BbGHBP was solubilized and refolded by dilution method using cysteine-cystine redox potential. The recombinant BbGHBP was purified and biological activity was checked on HeLa cell lines showing increase cell proliferation in the presence of ovine GH (oGH), hence justifying the increase in the half-life of GH in the presence of BbGHBP. For the molecular interactions of oGH-BbGHBP multiple docking programs were employed to explore the subsequent interactions which showed high binding affinity and presence of large number of hydrogen bonds. Molecular Dynamics studies performed to examine the stability of proteins and exhibited stable structures along with favorable molecular interactions. This study has described the sequence characterization of BbGHR in Nili-Ravi buffaloes and hence provided the basis for the assessment of GH-GHR binding in other Bovidae species.


Assuntos
Búfalos , Receptores da Somatotropina , Humanos , Ovinos/genética , Animais , Búfalos/genética , Búfalos/metabolismo , Receptores da Somatotropina/genética , Receptores da Somatotropina/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Células HeLa , Clonagem Molecular , Hormônio do Crescimento/genética , Hormônio do Crescimento/metabolismo
10.
Vaccines (Basel) ; 11(1)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36679976

RESUMO

Zika virus (ZIKV) pandemic and its implication in congenital malformations and severe neurological disorders had created serious threats to global health. ZIKV is a mosquito-borne flavivirus which spread rapidly and infect a large number of people in a shorter time-span. Due to the lack of effective therapeutics, this had become paramount urgency to discover effective drug molecules to encounter the viral infection. Various anti-ZIKV drug discovery efforts during the past several years had been unsuccessful to develop an effective cure. The NS2B-NS3 protein was reported as an attractive therapeutic target for inhibiting viral proliferation, due to its central role in viral replication and maturation of non-structural viral proteins. Therefore, the current in silico drug exploration aimed to identify the novel inhibitors of Zika NS2B-NS3 protease by implementing an e-pharmacophore-based high-throughput virtual screening. A 3D e-pharmacophore model was generated based on the five-featured (ADPRR) pharmacophore hypothesis. Subsequently, the predicted model is further subjected to the high-throughput virtual screening to reveal top hit molecules from the various small molecule databases. Initial hits were examined in terms of binding free energies and ADME properties to identify the candidate hit exhibiting a favourable pharmacokinetic profile. Eventually, molecular dynamic (MD) simulations studies were conducted to evaluate the binding stability of the hit molecule inside the receptor cavity. The findings of the in silico analysis manifested affirmative evidence for three hit molecules with -64.28, -55.15 and -50.16 kcal/mol binding free energies, as potent inhibitors of Zika NS2B-NS3 protease. Hence, these molecules holds the promising potential to serve as a prospective candidates to design effective drugs against ZIKV and related viral infections.

11.
Int J Biol Macromol ; 237: 124169, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36990409

RESUMO

The outbreak of novel Coronavirus, an enduring pandemic declared by WHO, has consequences to an alarming ongoing public health menace which has already claimed several million human lives. In addition to numerous vaccinations and medications for mild to moderate COVID-19 infection, lack of promising medication or therapeutic pharmaceuticals remains a serious concern to counter the ongoing coronavirus infections and to hinder its dreadful spread. Global health emergencies have called for urgency for potential drug discovery and time is the biggest constraint apart from the financial and human resources required for the high throughput drug screening. However, computational screening or in-silico approaches appeared to be an effective and faster approach to discover potential molecules without sacrificing the model animals. Accumulated shreds of evidence on computational studies against viral diseases have revealed significance of in-silico drug discovery approaches especially in the time of urgency. The central role of RdRp in SARS-CoV-2 replication makes it promising drug target to curtain on going infection and its spread. The present study aimed to employ E-pharmacophore-based virtual screening to reveal potent inhibitors of RdRp as potential leads to block the viral replication. An energy-optimised pharmacophore model was generated to screen the Enamine REAL DataBase (RDB). Then, ADME/T profiles were determined to validate the pharmacokinetics and pharmacodynamics properties of the hit compounds. Moreover, High Throughput Virtual Screening (HTVS) and molecular docking (SP & XP) were employed to screen the top hits from pharmacophore-based virtual screening and ADME/T screen. The binding free energies of the top hits were calculated by conducting MM-GBSA analysis followed by MD simulations to determine the stability of molecular interactions between top hits and RdRp protein. These virtual investigations revealed six compounds having binding free energies of -57.498, -45.776, -46.248, -35.67, -25.15 and -24.90 kcal/mol respectively as calculated by the MM-GBSA method. The MD simulation studies confirmed the stability of protein ligand complexes, hence, indicating as potent RdRp inhibitors and are promising candidate drugs to be further validated and translated into clinics in future.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Simulação de Acoplamento Molecular , Farmacóforo , RNA Polimerase Dependente de RNA , Simulação de Dinâmica Molecular
12.
Mol Biol Rep ; 39(6): 6399-408, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22528469

RESUMO

Proteases have prospective financial and environment-friendly applications; hence attention is focused currently on the finding of new protease producing microorganism so as to meet the requirements of industry. A thermophilic bacterial strain producing extracellular protease activity was isolated from soil and identified as Bacillus cereus by analysis of 16S rRNA. Protease production by the microorganism was improved by studying the impact of the type of nitrogen and carbon source, fermentation period, growth temperature and initial pH of the culture medium in cultivation optimization experiments. The enzyme was purified to homogeneity in two step procedure involving Sephadex G-75 and Q-Sepharose chromatography. The molecular weight of purified enzyme was found to be 58 kDa by SDS-PAGE. Protease exhibited a pH and temperature optima of 7.5 and 60°, respectively. The enzyme was active in the pH range of 6.0-9.0 and stable up to 70°C. Histological analysis of protease treated goat and cow skin pelts showed complete removal of non leather forming structures such as hair shaft, hair follicles and glandular structures. The protease showed the stain removing property from blood stained cotton cloth and found to be compatible with six commercially available detergents. The protease could release peptides from natural proteins after digestion of coagulated egg albumin and blood clot.


Assuntos
Bacillus cereus/enzimologia , Proteínas de Bactérias/química , Endopeptidases/química , Animais , Bacillus cereus/genética , Bacillus cereus/isolamento & purificação , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/isolamento & purificação , Proteínas Sanguíneas/química , Manchas de Sangue , Bovinos , Detergentes/química , Proteínas do Ovo/química , Endopeptidases/biossíntese , Endopeptidases/isolamento & purificação , Ensaios Enzimáticos , Estabilidade Enzimática , Cabras , Folículo Piloso/química , Remoção de Cabelo , Concentração de Íons de Hidrogênio , Tipagem Molecular , Peso Molecular , Proteólise , RNA Ribossômico 16S/genética , Pele/anatomia & histologia , Pele/química
13.
World J Microbiol Biotechnol ; 28(2): 513-22, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22806846

RESUMO

Delignification efficacy of xylanases to facilitate the consequent chemical bleaching of Kraft pulps has been studied widely. In this work, an alkaline and thermally stable cellulase-less xylanase, derived from a xylanolytic Bacillus subtilis, has been purified by a combination of gel filtration and Q-Sepharose chromatography to its homogeneity. Molecular weight of the purified xylanase was 61 kDa by SDS-PAGE. The purified enzyme revealed an optimum assay temperature and pH of 60°C and 8.0, respectively. Xylanase was active in the pH range of 6.0-9.0 and stable up to 70°C. Divalent ions like Ca(2+), Mg(2+) and Zn(2+) enhanced xylanase activity, whereas Hg(2+), Fe(2+), and Cu(2+) were inhibitory to xylanase at 2 mM concentration. It showed K ( m ) and V ( max ) values of 9.5 mg/ml and 53.6 µmol/ml/min, respectively, using birchwood xylan as a substrate. Xylanase exhibited higher values of turn over number (K (cat)) and catalytic efficiency (K (cat)/K (m)) with birchwood xylan than oat spelt xylan. Bleach-boosting enzyme activity at 30 U/g dry pulp displayed the optimum bio-delignification of Kraft pulp resulting in 26.5% reduction in kappa number and 18.5% ISO induction in brightness at 55°C after 3 h treatment. The same treatment improved the pulp properties including tensile strength and burst index, demonstrating its potential application in pre-bleaching of Kraft pulp.


Assuntos
Bacillus/enzimologia , Proteínas de Bactérias/metabolismo , Triticum/química , Xilosidases/metabolismo , Proteínas de Bactérias/química , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Temperatura , Xilosidases/química
14.
J Ayub Med Coll Abbottabad ; 24(2): 62-4, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-24397055

RESUMO

BACKGROUND: Breast cancer is a highly heterogeneous disease globally. The absolute risk of breast cancer increases with age and is higher in postmenopausal women. This study tried to find out role of serum trace elements (cadmium, cobalt, copper and zinc) and biomarkers in diagnosis of breast malignancy. METHODS: Levels of serum trace elements were estimated by atomic absorption spectrophotometry in serum samples of 23 breast cancer patients of stage III. Analysis of protein pattern was observed by sodium dodecyl polyacrylamide gel electrophoresis (SDS-PAGE). RESULTS: In menstruating women, the mean serum level of cadmium, copper and cobalt were significantly lowered as compared to control, however, zinc showed no significant difference. In premenopausal and postmenopausal women, the mean serum level of cadmium, copper, cobalt and zinc was decreased significantly in patients as compared to controls (p < 0.001). The ratio of Cu/Zn was also decreased in patients when compared to controls. Three major peptide bands with molecular weights of 33 kDa, 52 kDa and 185 kDa appeared in these samples when subjected to SDS PAGE. CONCLUSIONS: Serum trace elements are significantly lower in breast cancer patients compared to controls. The exact mechanism responsible for the alterations in trace element levels in patients with breast cancer is unclear and requires further evaluation. Gel electrophoresis may be important to find out breast cancer markers that may help in diagnosing the disease and response to treatment.


Assuntos
Neoplasias da Mama/sangue , Oligoelementos/sangue , Adulto , Idoso , Biomarcadores Tumorais/sangue , Feminino , Humanos , Pessoa de Meia-Idade
15.
Bioinform Biol Insights ; 16: 11779322221115547, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35966807

RESUMO

LHPP gene encodes a phospholysine phosphohistidine inorganic pyrophosphate phosphatase, which functions as a tumor-suppressor protein. The tumor suppression by this protein has been confirmed in various cancers, including hepatocellular carcinoma (HCC). LHPP downregulation promotes cell growth and proliferation by modulating the PI3K/AKT signaling pathway. This study identifies potentially deleterious missense single nucleotide variants (SNVs) associated with the LHPP gene using multiple computational tools based on different algorithms. A total of 4 destabilizing mutants are identified as L22P, I212T, G227R, and G236R, from the conserved region of the phosphatase. The 3-dimensional (3D) modeling and structural comparison of variants with the native protein reveals significant structural and conformational variations after mutations, suggesting disruption in the function of phospholysine phosphohistidine inorganic pyrophosphate phosphatase. The identified mutations might, therefore, participate in the cause of HCC.

16.
Mol Biol Rep ; 38(7): 4709-14, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21127983

RESUMO

Schizophrenia is a chronic and disabling disease of the brain. Schizophrenic patients have auditory hallucinations, delusions and reduced social skills. Recent studies suggest that the genetic polymorphisms are linked with development of schizophrenia. Polymorphisms of schizophrenia susceptibility and different cytokine genes act as the genetic markers. The objective of our study is to examine the association between the neuregulin 1 and tumor necrosis factor-α (-308) gene polymorphism with schizophrenia. This association was performed on the basis of molecular biology to screen the mutations of neuregulin 1 and tumor necrosis factor-α (-308) gene in schizophrenic patients by polymorphism analysis. Statistical analysis of the observed data shows that there was an association (P = 0.003) between patient's group and controls in terms of genotypes of single-nucleotide polymorphism 1 rather than single-nucleotide polymorphism 2 of neuregulin 1. So, heterozygous (adenine/guanine) allelic pattern can be a higher risk factor of schizophrenic patients. Polymorphism of tumor necrosis factor-α (-308) gene indicated frequent presence of homozygous (adenine/adenine) allelic pattern in patient's group than in controls (P = 0.015). Statistical analysis indicates that the age distribution has significant difference between patient's group and controls (P = 0.022) while the gender ratio is not significantly different (P = 0.366) between the two groups. It was concluded that in Pakistani population the neuregulin 1 and tumor necrosis factor-α (-308) genes are strongly associated with schizophrenia.


Assuntos
Predisposição Genética para Doença , Hospitais , Neuregulina-1/genética , Polimorfismo de Nucleotídeo Único/genética , Esquizofrenia/genética , Fator de Necrose Tumoral alfa/genética , Adolescente , Adulto , Criança , Eletroforese em Gel de Ágar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Adulto Jovem
17.
Mol Biol Rep ; 38(5): 2953-60, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20107908

RESUMO

Granzymes kill cells in a variety of ways. They induce mitochondrial dysfunction through caspase dependent and caspase-independent pathways and destroy DNA and the integrity of the nucleus. For gaining a better understanding of the molecular function of granzyme M and its NK cell specificity, structural characterization of this enzyme by molecular modeling as well as its detailed comparison with other granzymes is presented in this study. The study includes mode of action of granzyme M using cationic binding sites, substrate specificity, post-translational structural modification and its functional relationship and interaction of the enzyme with inhibitor in an attempt to explore how the activity of human granzyme M is controlled under physiological conditions. It is concluded from the present study that the post-translational modification, including Oglycosylation of serine, phosphorylation of serine and threonine and myristoylation of glycine, play an important role in the interaction of enzyme with the cell surface membrane and regulate protein trafficking and stability. Phosphorylated serine and threonine also plays a role in tumor elimination, viral clearance and tissue repair. In Gzm M there are cationic sites, cs1 and cs2 that may participate in binding of Gzm M to the cell surface, thereby promoting its uptake and eventual release into the cytoplasm. Gzm M shows apoptotic activity both by caspase dependent and independent pathways. Modeling of inhibitors bound to the granzyme active site shows that the dimer also contributes to substrate specificity in a unique manner by extending the active-site cleft.


Assuntos
Granzimas/antagonistas & inibidores , Granzimas/química , Granzimas/metabolismo , Processamento de Proteína Pós-Traducional , Estrutura Terciária de Proteína , Inibidores de Serina Proteinase/química , Inibidores de Serina Proteinase/metabolismo , Apoptose/fisiologia , Sítios de Ligação , Granzimas/genética , Humanos , Ligação de Hidrogênio , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Especificidade por Substrato
18.
Bioinform Biol Insights ; 15: 11779322211043297, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34566410

RESUMO

In cancer treatment, immunotherapy has great potential for improving the prognosis of patients with hematologic and solid malignancies. In this study, various bioinformatics tools and servers were used to design an antiangiogenic fusion protein. After comprehensive evaluation, an antiangiogenic fusion protein was designed using a soluble extracellular domain of human vascular endothelial growth factor receptor 1 (sVEGFR-1) and human interleukin-2 (IL-2) joined by a flexible linker. The final construct was composed of 875 amino acids. The secondary structure of the fusion protein, obtained by CFSSP, PSIPRED, and SOPMA tools, consisted of 14.17% helices, 29.71% extended strands, 4.69% beta turns and 51.43% random coils. Tertiary structure prediction by Raptor X showed that the fusion protein comprises 3 domains with 875 modeled amino acids, out of which 26 positions (2%) were considered disordered. The Ramachandran plot revealed 89.3%, 7.1%, and 3.6% amino acid residues in favored, allowed, and outlier regions, respectively. Physical features of the Molecular Dynamic (MD) simulated system such as root mean square deviation, root mean square fluctuation, solvent-on hand surface region, and radius of gyration identified the fusion construct as a stable and compact protein with few fluctuations in its overall structure. Docking of the fusion protein showed that interaction between sVEGFR-1/VEGFA and IL-2/IL-2R still exists. In silico analysis revealed that the fusion protein comprising IL-2 and sVEGFR-1 has stable structure and the selected linker can efficiently separate the two domains. These observations may be helpful in determining protein stability prior to protein expression.

19.
Expert Opin Biol Ther ; 21(11): 1525-1533, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34547976

RESUMO

OBJECTIVES: The design of peptide-based vaccines for cancer is a promising immunotherapy that can induce a cancer-specific cytotoxic response in tumor cells. METHODS: Herein, we used the immunoinformatic approach in designing a multi-epitope vaccine targeting G-protein coupled receptor 87 (GPCR-87), cystine/glutamate transporter (SLC7A11), Immunoglobulin binding protein 1 (IGBP1), and thioredoxin domain-containing protein 5 (TXNDC5), which can potentially contribute to NSCLC. The MHC-I and MHC-II epitopes selected for the fusion construct were evaluated for their antigenic and non-allergenic natures via VaxiJen and AllerTop. RESULTS: A total of five epitopes, four class-I (FIFYLKNIV, CRYTSVLFY, RYLKVVKPF, and RQAKIQRYK), and one class-II (NQVRGYPTLLWFRDG), having combined USA population coverage of 100%, were used to make ten possible multi-epitope fusion constructs. In these constructs, PADRE, a universal T-helper epitope, and RSO9, a TLR4 agonist, were fused as adjuvants. The molecular docking analysis revealed that two constructs were showing significant binding affinities toward HLA-A*02:01, the most prevalent HLA allele in USA. Moreover, MD simulations marked one construct as a promising therapeutic candidate. CONCLUSION: The multi-epitope vaccine constructs designed using immunogenic, and non-allergenic peptides of NSCLS tumor-associated proteins are likely to pose significant therapeutic efficacies in cancer immunotherapy due to their high binding affinities toward HLA molecules.


Assuntos
Vacinas Anticâncer/imunologia , Carcinoma Pulmonar de Células não Pequenas , Antígenos HLA , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/terapia , Biologia Computacional , Epitopos de Linfócito B , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Simulação de Acoplamento Molecular , Estados Unidos , Vacinas de Subunidades Antigênicas
20.
Mol Biol Rep ; 37(4): 1717-23, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19562510

RESUMO

Consistent with its precloning characterization from the cellulolytic Bacillus sp., beta-1,4-endoglucanase purified from the recombinant E. coli exhibited maximum activity at 60 degrees C and pH 7.0. It was highly specific for CMC hydrolysis, with stability up to 70 degrees C and over a pH range of 6.0-8.0. The K(m) and V(max) values for CMCase activity of the enzyme were 4.1 mg/ml and 25 micromole/ml min(-1), respectively. The purified enzyme was a monomer of 65 kDa, as determined by SDS-PAGE. The presence of sucrose and IPTG in fermentation media increased the endoglucanase activity of the recombinant enzyme to 5.2-folds as compared with that of the actual one.


Assuntos
Bacillus/enzimologia , Celulase/genética , Celulase/isolamento & purificação , Cromatografia em Gel , Cromatografia por Troca Iônica , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática , Escherichia coli , Concentração de Íons de Hidrogênio , Peso Molecular , Recombinação Genética , Temperatura , Transformação Genética
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