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1.
J Biomol Struct Dyn ; : 1-18, 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38502688

ABSTRACT

Bell's palsy (BP) can result in facial paralysis. Inflammation or injury to the cranial nerves that regulate the facial muscles is primarily responsible for that disease. Commiphora wightii remains recognized as a cure for a few human ailments. This study focused on therapeutic phenomena of C. wightii for the treatment of Bell's palsy, utilizing the network drug discovery and molecular docking techniques. Active biological constituents of C. wightii were retrieved from literature and independent databases. Potential therapeutic targets (431) of 13 bioactive phytochemicals were fetched via SwissTargetPrediction tool. Putative intersecting targets (855) of Bell's palsy were computed through the DisGeNET and GeneCards datasets. Subsequently, by the analysis of potential shared targets (87) of C. wightii and Bell's palsy, a Venn diagram was drawn. DAVID database was used to evaluate gene functional annotations and enriched pathways that are involved in Bell's palsy. STRING database was used for generating the protein-protein relationship complex. Visual presentations of the interactions of potential targets to active chemical constituents were done by the Cytoscape. Whereas, the conformational research sorted out 10 key targets through the protein-protein interactions network. Moreover, the capacity of therapeutic ingredients to interact with a target inhibiting Bell's palsy was confirmed by molecular docking, which might ratify the findings of network pharmacology. In the molecular complex of AKT1-cholesterol, a 100-ns simulation unveiled a graceful stability, with a minimal 0.167 Å ligand shift and resilient hydrogen bonds (ASN54 and SER205). The final 20 ns showcased a P1 motif pirouette, gracefully forming aromatic bonds with H165 and W186, underscoring the complex's dynamic finesse. This study evaluated compound-target interactions and their impact on disease-related genes. It revealed that five genes (AKT1, TNF, MAPK3, EGFR and SRC) of C. wightii might be useful therapeutic targets for the treatment of Bell's palsy, as well as helping in lowering down the blood pressure.Communicated by Ramaswamy H. Sarma.

2.
J Biomol Struct Dyn ; 41(24): 14715-14729, 2023.
Article in English | MEDLINE | ID: mdl-37301608

ABSTRACT

Breast cancer is a silent killer malady among women and a serious economic burden in health care management. A case of breast cancer is diagnosed among women every 19 s, and every 74 s, a woman dies of breast cancer somewhere in the world. Despite the pop-up of progressive research, advanced treatment approaches, and preventive measures, breast cancer remains amplifying ailment. The nuclear factor kappa B (NF-κB) is a key transcription factor that links inflammation with cancer and is demonstrated as being involved in the tumorigenesis of breast cancer. The NF-κB transcription factor family in mammals consists of five proteins; c-Rel, RelA(p65), RelB, NF-κB1(p50), and NF-κB2(p52). The antitumor effect of NF-κB has also been explored in breast cancer, however, the actual treatment for breast cancer is yet to be discovered. This study is attributed to the identification of novel drug targets against breast cancer by targeting c-Rel, RelA(p65), RelB, NF-κB1(p50), and NF-κB2(p52) proteins. To identify the putative active compounds, a structure-based 3D pharmacophore model to the protein active site cavity was generated followed by virtual screening, molecular docking, and molecular dynamics (MD) simulation. Initially, a library of 45000 compounds were docked against the target protein and five compounds namely Z56811101, Z653426226, Z1097341967, Z92743432, and Z464101066 were selected for further analysis. The relative binding affinity of Z56811101, Z653426226, Z1097341967, Z92743432, and Z464101066 with NF-κB1 (p50), NF-κB2 (p52), RelA (p65), RelB, and c-Rel proteins were -6.8, -8, -7.0, -6.9, and -7.2 kcal/mol, respectively which remained stable throughout the simulations of 200 ns. Furthermore, all of these compounds depict maximum drug-like properties. Therefore, the proposed compounds can be a potential candidate for patients with breast cancer, but, experimental validation is needed to ensure their safety.Communicated by Ramaswamy H. Sarma.


Subject(s)
Breast Neoplasms , NF-kappa B , Animals , Humans , Female , NF-kappa B/metabolism , NF-kappa B p52 Subunit/metabolism , Breast Neoplasms/drug therapy , Molecular Docking Simulation , NF-kappa B p50 Subunit/metabolism , Mammals/metabolism
3.
J Biosci ; 482023.
Article in English | MEDLINE | ID: mdl-37021675

ABSTRACT

Plastics are indispensable and typically derived from non-renewable sources. The extensive production and indiscriminate use of synthetic plastics pose a serious threat to the environment and lead to problems due to their non-biodegradability. Various forms of plastics that are used in daily life should be limited and replaced by biodegradable materials. To deal with the challenges of sustainability or environmental issues that occur due to the production and disposal of synthetic plastics, biodegradable and environment-friendly plastics are crucial. Utilizing renewable sources such as keratin derived from chicken feathers and chitosan from shrimp cell wastes as an alternative to obtain safe bio-based polymers has gained much attention because of rising environmental issues. Approximately, 2-5 billion tons of waste are produced by the poultry and marine industries each year, adversely impacting the environment. These polymers are more acceptable and ecofriendly compared with conventional plastics due to their biostability, biodegradability, and excellent mechanical properties. The replacement of synthetic plastic packaging with biodegradable polymers from animal by-products significantly reduces the volume of waste generated. This review highlights important aspects such as the classification of bioplastics, properties and use of waste biomass for bioplastics production, their structure, mechanical properties, and demand in industrial sectors such as agriculture, biomedicine, and food packaging.


Subject(s)
Plastics , Poultry , Animals , Biomass , Plastics/chemistry , Polymers , Biopolymers
4.
PeerJ ; 11: e14754, 2023.
Article in English | MEDLINE | ID: mdl-36778156

ABSTRACT

Fusarium cotton wilt is a devastating disease of the cotton crop throughout the world, caused by Fusarium oxysporum f.sp. vasinfectum (FOV). Chemical control has many side effects, so, biological controls have been widely used for the management of Fusarium wilt. This study aimed to investigate the possible use of an actinomycetes Saccharothrix algeriensis (SA) NRRL B-24137 to control FOV. To access in-vitro anti-Fusarium ability of SA NRRL B-24137, dual culture assay, spore germination and seed germination tests were carried out. Following in-vitro investigations, several pot tests in a greenhouse environment were used to evaluate the biological control potential of SA NRRL B-24137 against FOV. Dual culture assay and spore germination revealed that SA NRRL B-24137 showed significant anti-Fusarium activity.During spore germination 87.77% inhibition of spore germination were observed. In pot experiments, SA NRRL B-24137 primed cotton seeds resulted in a 74.0% reduction in disease incidence. In soil there was a significant reduction in FOV spores in the presence of SA NRRL B-24137. Positive correlation was also observed on different concentrations of SA NRRL B-24137 towards FOV reduction. The results of this study showed that SA NRRL B-24137 has the potential to be employed as a biocontrol agent against Fusarium cotton wilt, improving cotton growth characteristics and yield.


Subject(s)
Fusarium , Cottonseed Oil/pharmacology
5.
Pharmaceutics ; 14(9)2022 Sep 19.
Article in English | MEDLINE | ID: mdl-36145718

ABSTRACT

Epithelial ovarian cancer (EOC) is one of the deadliest reproductive tract malignancies that form on the external tissue covering of an ovary. Cassia fistula is popular for its anti-inflammatory and anticarcinogenic properties in conventional medications. Nevertheless, its molecular mechanisms are still unclear. The current study evaluated the potential of C. fistula for the treatment of EOC using network pharmacology approach integrated with molecular docking. Eight active constituents of C. fistula were obtained from two independent databases and the literature, and their targets were retrieved from the SwissTargetPrediction. In total, 1077 EOC associated genes were retrieved from DisGeNET and GeneCardsSuite databases, and 800 potential targets of eight active constituents of C. fistula were mapped to the 1077 EOC targets and intersected targets from two databases. Ultimately, 98 potential targets were found from C. fistula for EOC. Finally, the protein-protein interaction network (PPI) topological interpretation revealed AKT1, CTNNB1, ESR1, and CASP3 as key targets. This is the first time four genes have been found against EOC from C. fistula. The major enriched pathways of these candidate genes were established by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) investigations. To confirm the network pharmacology findings, the molecular docking approach demonstrated that active molecules have higher affinity for binding to putative targets for EOC suppression. More pharmacological and clinical research is required for the development of a drug to treat EOC.

6.
PLoS One ; 16(12): e0261111, 2021.
Article in English | MEDLINE | ID: mdl-34910751

ABSTRACT

Stenotrophomonas maltophilia is a multidrug resistant pathogen associated with high mortality and morbidity in patients having compromised immunity. The efflux systems of S. maltophilia include SmeABC and SmeDEF proteins, which assist in acquisition of multiple-drug-resistance. In this study, proteome based mapping was utilized to find out the potential drug targets for S. maltophilia strain k279a. Various tools of computational biology were applied to remove the human-specific homologous and pathogen-specific paralogous sequences from the bacterial proteome. The CD-HIT analysis selected 4315 proteins from total proteome count of 4365 proteins. Geptop identified 407 essential proteins, while the BlastP revealed approximately 85 non-homologous proteins in the human genome. Moreover, metabolic pathway and subcellular location analysis were performed for essential bacterial genes, to describe their role in various cellular processes. Only two essential proteins (Acyl-[acyl-carrier-protein]-UDP-N acetyl glucosamine O-acyltransferase and D-alanine-D-alanine ligase) as candidate for potent targets were found in proteome of the pathogen, in order to design new drugs. An online tool, Swiss model was employed to model the 3D structures of both target proteins. A library of 5000 phytochemicals was docked against those proteins through the molecular operating environment (MOE). That resulted in to eight inhibitors for both proteins i.e. enterodiol, aloin, ononin and rhinacanthinF for the Acyl-[acyl-carrier-protein]-UDP-N acetyl glucosamine O-acyltransferase, and rhazin, alkannin beta, aloesin and ancistrocladine for the D-alanine-D-alanine ligase. Finally the ADMET was done through ADMETsar. This study supported the development of natural as well as cost-effective drugs against S. maltophilia. These inhibitors displayed the effective binding interactions and safe drug profiles. However, further in vivo and in vitro validation experiment might be performed to check their drug effectiveness, biocompatibility and their role as effective inhibitors.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Delivery Systems , Molecular Docking Simulation , Stenotrophomonas maltophilia/drug effects , Subtractive Hybridization Techniques , Bacterial Proteins/analysis , Bacterial Proteins/antagonists & inhibitors , Bacterial Proteins/chemistry , Models, Molecular , Protein Conformation , Proteome
7.
Arch Microbiol ; 203(9): 5417-5423, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34402947

ABSTRACT

Plastics are usually made up of low-density polyethylene (LDPE) that serve as the environmental nuisance. The recalcitrant nature of plastics is a huge concern, whereas the increasing demand has made it difficult to handle the plastic waste that eventually leads to plastic pollution. In recent years, due to increasing demand and high pressure for its safe disposal, plastic biodegradation has gained a lot of attention. In the current study, four bacterial strains were isolated from the solid-waste dumpsites of Faisalabad, Pakistan, using enrichment culture technique. The isolated bacterial strains were capable of growing on media having polystyrene as the sole carbon source. Based on 16S rRNA gene sequencing and phylogenetic analysis of the isolated strains Serratia sp., Stenotrophomonas sp. and Pseudomonas sp. were identified as the potential strains for the biodegradation of LDPE. Serratia sp. resulted in 40% weight loss of the LDPE plastic pieces after 150 days of treatment. Stenotrophomonas sp. and Pseudomonas species resulted in 32 and 21% weight loss of the treated piece of plastics (LDPE), respectively. Polyethylene pieces were characterized by Fourier-transform infrared spectroscopy (FTIR) analysis before and after biodegradation. The FTIR spectra indicated that the isolated bacterial strains have a good potential to degrade LDPE. Future studies are required to investigate the bacterial genetic makeup, mechanisms of LDPE biodegradation and the factors that can enhance the biodegradable characteristics of these indigenously isolated bacterial strains.


Subject(s)
Bacteria , Polyethylene , Bacteria/genetics , Biodegradation, Environmental , Phylogeny , RNA, Ribosomal, 16S/genetics
8.
Environ Sci Pollut Res Int ; 28(22): 28307-28318, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33537856

ABSTRACT

Discharge of untreated textile wastewaters loaded with dyes is not only contaminating the soil and water resources but also posing a threat to the health and socioeconomic life of the people. Hence, there is a need to devise the strategies for effective treatment of such wastewaters. The present study reports the catalytic potential of biogenic ZnO nanoparticles (ZnO NPs) synthesized by using a bacterial strain Pseudochrobactrum sp. C5 for degradation of dyes and wastewater treatment. The catalytic potential of the biogenic ZnO NPs for degradation of dyes and wastewater treatment was also compared with that of the chemically synthesized ones. The characterization of the biogenic ZnO NPs through FT-IR, XRD, and field emission scanning electron microscopy (FESEM) indicated that these are granular agglomerated particles having a size range of 90-110 nm and zeta potential of -27.41 mV. These catalytic NPs had resulted into almost complete (> 90%) decolorization of various dyes including the methanol blue and reactive black 5. These NPs also resulted into a significant reduction in COD, TDS, EC, pH, and color of two real wastewaters spiked with reactive black 5 and reactive red 120. The findings of this study suggest that the biosynthesized ZnO NPs might serve as a potential green solution for treatment of dye-loaded textile wastewaters.


Subject(s)
Metal Nanoparticles , Nanoparticles , Water Purification , Zinc Oxide , Coloring Agents , Humans , Spectroscopy, Fourier Transform Infrared
9.
Sci Rep ; 10(1): 20017, 2020 11 18.
Article in English | MEDLINE | ID: mdl-33208758

ABSTRACT

Polyphenols based bioactive compounds from vegetables and fruits are known for impressive antioxidant activity. Ingestion of these antioxidants may promote human health against cardiovascular diseases and cancer. Mango is a popular tropical fruit with special taste, high nutritional value and health-enhancing metabolites. The aim was to investigate the diversity of phytochemicals between two mango cultivars of china at three stages of fruit maturity. We used ESI-QTRAP-MS/MS approach to characterize comprehensively the metabolome of two mango cultivars named Hongguifei (HGF) and Tainong (TN). HPLC was used to quantify selected catechin based phenolic compounds. Moreover, real-time qPCR was used to study the expression profiles of two key genes (ANR and LAR) involved in proanthocyanidin biosynthesis from catechins and derivatives. A total of 651 metabolites were identified, which include at least 257 phenolic compounds. Higher number of metabolites were differentially modulated in peel as compared to pulp. Overall, the relative quantities of amino acids, carbohydrates, organic acids, and other metabolites were increased in the pulp of TN cultivar. While the contents of phenolic compounds were relatively higher in HGF cultivar. Moreover, HPLC based quantification of catechin and derivatives exhibited cultivar specific variations. The ANR and LAR genes exhibited an opposite expression profile in both cultivars. Current study is the first report of numerous metabolites including catechin-based derivatives in mango fruit. These findings open novel possibilities for the use of mango as a source of bioactive compounds.


Subject(s)
Fruit/metabolism , Mangifera/metabolism , Metabolome , Phytochemicals/analysis , Plant Extracts/metabolism , Spectrometry, Mass, Electrospray Ionization/methods , Tandem Mass Spectrometry/methods , China , Fruit/chemistry , Mangifera/chemistry , Mangifera/classification , Nutritive Value , Plant Extracts/analysis , Plant Extracts/chemistry
10.
Biomed Res Int ; 2020: 6398165, 2020.
Article in English | MEDLINE | ID: mdl-32382563

ABSTRACT

Antibiotic resistance against present antibiotics is rising at an alarming rate with need for discovery of advanced methods to treat infections caused by resistant pathogens. Silver nanoparticles are known to exhibit satisfactory antibacterial and antibiofilm activity against different pathogens. In the present study, the AgNPs were synthesized chemically and characterized by UV-Visible spectroscopy, scanning electron microscopy, and X-ray diffraction. Antibacterial activity against MDR K. pneumoniae strains was evaluated by agar diffusion and broth microdilution assay. Cellular protein leakage was determined by the Bradford assay. The effect of AgNPs on production on extracellular polymeric substances was evaluated. Biofilm formation was assessed by tube method qualitatively and quantitatively by the microtiter plate assay. The cytotoxic potential of AgNPs on HeLa cell lines was also determined. AgNPs exhibited an MIC of 62.5 and 125 µg/ml, while their MBC is 250 and 500 µg/ml. The production of extracellular polymeric substance decreased after AgNP treatment while cellular protein leakage increased due to higher rates of cellular membrane disruption by AgNPs. The percentage biofilm inhibition was evaluated to be 64% for K. pneumoniae strain MF953600 and 86% for MF953599 at AgNP concentration of 100 µg/ml. AgNPs were evaluated to be minimally cytotoxic and safe at concentrations of 15-120 µg/ml. The data evaluated by this study provided evidence of AgNPs being safe antibacterial and antibiofilm compounds against MDR K. pneumoniae.


Subject(s)
Biofilms/drug effects , Drug Resistance, Multiple, Bacterial/drug effects , Klebsiella pneumoniae/physiology , Metal Nanoparticles/chemistry , Silver/pharmacology , Biofilms/growth & development , Silver/chemistry
11.
Arch Microbiol ; 202(5): 967-981, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32052094

ABSTRACT

L-asparaginase (E.C.3.5.1.1) is an important enzyme that has been purified and characterized for over decades to study and evaluate its anti-carcinogenic activity against different lymphoproliferative disorders such as acute lymphoblastic leukemia (ALL) and Hodgkin's lymphoma. The ability of the enzyme to convert L-asparagine into aspartic acid and ammonia is the reason behind its anti-cancerous activity. Apart from its medicinal uses, it is widely used in food industry to tackle acrylamide, a probable human carcinogen and, production in carbohydrate-rich foods cooked at high temperatures. There are variety of organisms including microorganisms such as bacteria, fungi, algae, and plants that produce L-asparaginase. The enzyme obtained from different microbial and plant sources have different physiochemical properties and kinetic parameters. L-asparaginases have an optimum pH range between 6 and 10 and an optimum temperature between 37 and 85 °C. This article has reviewed the lowest molecular mass for L-asparaginase in Yersinia pseudotuberculosis Q66CJ2 which is 36.27 kDa, while the highest for Pseudomonas otitidis which has a molecular mass of 205 ± 3 kDa. This review is an attempt to summarize most of the available sources, their phylogenetic relationships, purification methods, data regarding different physiochemical and kinetic properties of L-asparaginase.


Subject(s)
Asparaginase/chemistry , Bacteria/enzymology , Fungi/enzymology , Hodgkin Disease/drug therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Ammonia/metabolism , Asparaginase/genetics , Asparaginase/isolation & purification , Asparagine/chemistry , Aspartic Acid/metabolism , Humans , Phylogeny , Plants
12.
Genomics ; 112(2): 1371-1383, 2020 03.
Article in English | MEDLINE | ID: mdl-31415811

ABSTRACT

The two-component system (TCS) plays an important role in signal transduction pathways, cytokinin signaling and stress resistance of prokaryotes and eukaryotes. It is comprised of three types of proteins in plants; histidine kinases (HKs), histidine phosphotransfer proteins (HPs) and response regulators (RRs). Chickpea (Cicer arietinum L.) is one of the most important legume crops worldwide with special economic value in semi-arid tropics. Availability of complete genome sequence of chickpea presents a valuable resource for comparative analysis among angiosperms. In current study, Arabidopsis thaliana and Oryza sativa were used as reference plant species for comparative genomics analysis with C. arietinum. A genome-wide computational survey enabled us to identify putative members of TCS protein family including 18HKs, 26 RRs (7 type-A, 7 type-B, 2 type C and 10 pseudo) and 7 HPs (5 true and 2pseudo) genes in chickpea. The predicted TCS genes displayed family specific intron/exon organization and were randomly distributed across all the eight chromosomes. Comparative phylogenetic and evolutionary analysis suggested a variable conservation of TCS genes in relation to mono/dicot model plants and segmental duplication was the principal route of expansion for this family in chickpea. The promoter regions of TCS genes exhibited several abiotic stress-related cis-elements indicating their involvement in abiotic stress response. The expression analysis of TCS genes demonstrated stress (drought, heat, osmotic and salt) specific differential expression. Current study provides insight into TCS genes in C. arietinum, which will be helpful for further functional analysis of these genes in response to different abiotic stresses.


Subject(s)
Cicer/genetics , Gene Expression Regulation, Plant , Histidine Kinase/genetics , Phosphotransferases/genetics , Phytochrome/genetics , Plant Proteins/genetics , Receptors, Cell Surface/genetics , Chromosomes, Plant/genetics , Cicer/metabolism , Histidine Kinase/metabolism , Phosphotransferases/metabolism , Phytochrome/metabolism , Plant Proteins/metabolism , Receptors, Cell Surface/metabolism , Response Elements , Stress, Physiological
13.
Protein Pept Lett ; 25(2): 208-219, 2018.
Article in English | MEDLINE | ID: mdl-29384047

ABSTRACT

BACKGROUND: Cellulose represents a major source of fermentable sugars in lignocellulosic biomass and a combined action of hydrolytic enzymes (exoglucanases , endoglucanases and ß-glucosidases) is required to effectively convert cellulose to glucose that can be fermented to bio-ethanol. However, in-order to make the production of bio-ethanol an economically feasible process, the costs of the enzymes to be used for hydrolysis of the raw material need to be reduced and an increase in specific activity or production efficiency of cellulases is required. Among the cellulases, ß-glucosidase not only hydrolyzes cellobiose to glucose but it also reduces the cellobiose inhibition, resulting in efficient functioning of endo- and exo-glucanases. Therefore, in the current study kinetic and thermodynamic characteristics of highly active ß-glucosidase from randomly mutated Aspergillus niger NIBGE-06 have been evaluated for its industrial applications. OBJECTIVE: The main objective of this study was the identification of mutations and determination of their effect on the physiochemical, kinetic and thermodynamic characteristics of ß-glucosidase activity and stability. METHODS: Pure cultures of Aspergillus niger NIBGE and its 2-Deoxy-D-glucose resistant γ-rays mutant Aspergillus niger NIBGE-06 were grown on Vogel's medium containing wheat bran (3% w/v), at 30±1 °C for 96-108 h. Crude enzymes from both strains were subjected to ammonium sulfate precipitation and column chromatography on Fast Protein Liquid Chromatography (FPLC) system. The purified ß-glucosidases from both fungal sources were characterized for their native and subunit molecular mass through FPLC and SDS-PAGE, respectively. The purified enzymes were then comparatively characterized for their optimum temperature, activation energy (Ea), temperature quotient (Q10), Optimum pH, Heat of ionization (ΔHI) of active site residues , Michaelis-Menten constants (Vmax, Km, kcat and kcat/Km) and thermodynamics of irreversible inactivation through various enzyme assays. The genomic DNA from both fungal strains was also extracted by SDS-method and full length ß- glucosidase genes (bgl) were amplified through PCR. The PCR products were cloned in TA cloning vector followed by the sequencing of potentially full length clones using the commercial services of Macrogen, Korea. The in silico analyses of the sequences thus obtained were also performed using various online tools such as blastn, blastp, GeneWise, SignalP, Inter- ProScan. RESULTS: The extracellular ß-glucosidases (BGL) from both fungal sources were purified to homogeneity level by ammonium sulfate precipitation and FPLC system. The BGLs from both strains were dimeric in nature, with subunit and native molecular masses of 130 kDa and 252 kDa, respectively. The comparative analysis of nucleotides of bgl genes revealed 8 point mutations. Significant improvement was observed in the kinetic properties of the mutant BGL relative to the wild type enzyme. Arrhenius plot for energy of activation (Ea) showed a biphasic trend and ES-complex formation required Ea of 50 and 42 kJ mol-1 by BGL from parent and mutant, respectively. The pKa1 and pKa2 of the active site residues were 3.4 & 5.5 and 3.2 & 5.6, respectively. The heat of ionization for the acidic limb (ΔHI-AL) and the basic limb (ΔHI-BL) of BGL from both strains were equal to 56 & 41 and 71 & 45 kJ mol-1, respectively. Kinetic constants of cellobiose hydrolysis for BGL from both strains were determined as follows: kcat = 2,589 and 4,135 s-1, Km = 0.24 and 0.26 mM cellobiose, kcat/Km = 10,872 and 15,712 s-1 mM-1 cellobiose, respectively. Thermodynamic parameters for cellobiose hydrolysis also suggested that mutant BGL is more efficient compared to the parent enzyme. Comparative analysis of Ea(d), ΔH* and ΔG* for irreversible thermostability indicated that the thermostabilization of mutant enzyme was due to higher functional energy (free energy), which enabled the enzyme to resist against unfolding of its transition state. CONCLUSION: Physiochemical and thermodynamic characterization of extracellular ß-glucosidases (BGL) from 2-Deoxy-Dglucose resistant mutant derivative of A. niger showed that mutagenesis did not greatly affect the physiochemical properties of the BGL enzyme, like temperature optima, pH optima and molecular mass, while the catalytic efficiency for cellobiose hydrolysis was significantly improved (High kcat and kcat/Km). Furthermore, the mutant BGL was more thermostable than the parent enzyme. This shows that random mutagenesis has changed the BGL structural gene, resulting in improvement within its stability- function characteristics. Hence, directed evolution or random mutagenesis with careful selection can result in the engineering of highly efficient enzymes for intended industrial applications.


Subject(s)
Aspergillus niger/enzymology , Biofuels , Ethanol/chemistry , Lignin/metabolism , beta-Glucosidase/metabolism , Catalysis , Cellobiose/chemistry , Cellobiose/metabolism , Fermentation , Hydrogen-Ion Concentration , Hydrolysis , Kinetics , Lignin/chemistry , Molecular Weight , Mutation , Peptide Hydrolases/metabolism , Temperature , Thermodynamics , Urea/metabolism , beta-Glucosidase/isolation & purification
14.
Prog Biophys Mol Biol ; 132: 23-34, 2018 01.
Article in English | MEDLINE | ID: mdl-28774751

ABSTRACT

Lipase (E.C.3.1.1.3) belongs to the hydrolases and is also known as fat splitting, glycerol ester hydrolase or triacylglycerol acylhydrolase. Lipase catalyzes the hydrolysis of triglycerides converting them to glycerol and fatty acids in an oil-water interface. These are widely used in food, dairy, flavor, pharmaceuticals, biofuels, leather, cosmetics, detergent, and chemical industries. Lipases are of plant, animal, and microbial origin, but microbial lipases are produced at industrial level and represent the most widely used class of enzymes in biotechnological applications and organic chemistry. Phylogenetic analysis and comparison of residues around GxSxG motif provided an insight to the diversity among bacterial lipases. A variety of para-Nitrophenyl (p-NP) esters having C2 to C16 (p-NP acetate to p-NP palmitate) in their fatty acid side chain can be hydrolyzed by bacterial lipases. Large heterogeneity has been observed in molecular and catalytic characteristics of lipases including molecular mass; 19-96 kDa, Km; 0.0064-16.58 mM, Kcat; 0.1665-1.0 × 104 s-1 and Kcat/Km; 26.02-7377 s-1/mM. Optimal conditions of their working temperature and pH have been stated 15-70 °C and 5.0-10.8, respectively and are strongly associated with the type and growth conditions of bacteria. Surface hydrophobicity, enzyme activity, stability in organic solvents and at high temperature, proteolytic resistance and substrate tolerance are the properties of bacterial lipases that have been improved by engineering. Bacterial lipases have been extensively studied during last decade. However, their wider applications demand a detailed review on purification, catalytic characterization and applications of lipases.


Subject(s)
Bacteria/enzymology , Lipase/isolation & purification , Lipase/metabolism , Animals , Bacteria/metabolism , Humans , Lipase/biosynthesis , Lipase/genetics , Phylogeny , Protein Engineering
15.
Environ Sci Pollut Res Int ; 23(11): 11224-11239, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26920535

ABSTRACT

Remediation of colored wastewater loaded with dyes and metal ions is a matter of interest nowadays. In this study, 220 bacteria isolated from textile wastewater were tested for their potential to decolorize each of the four reactive dyes (reactive red-120, reactive black-5, reactive yellow-2, and reactive orange-16) in the presence of a mixture of four different heavy metals (Cr, Zn, Pb, Cd) commonly found in textile effluents. Among the tested bacteria, the isolate ZM130 was found to be the most efficient in decolorizing reactive dyes in the presence of the mixture of heavy metals and was identified as Pseudomonas aeruginosa strain ZM130 by 16S rRNA gene analysis. The strain ZM130 was highly effective in simultaneously removing hexavalent chromium (25 mg L(-1)) and the azo dyes (100 mg L(-1)) from the simulated wastewater even in the presence of other three heavy metals (Zn, Pb, Cd). Simultaneous removal of chromium and azo dyes ranged as 76.6-98.7 % and 51.9-91.1 %, respectively, after 180 h incubation. On the basis of quadratic polynomial equation and response surfaces given by the response surface methodology (RSM), optimal salt content, pH, carbon co-substrate content, and level of multi-metal mixtures for decolorization of reactive red-120 in a simulated textile wastewater by the strain ZM130 were predicted to be 19.8, 7.8, and 6.33 g L(-1) and a multi-metal mixture (Cr 13.10 mg L(-1), Pb 26.21 mg L(-1), Cd 13.10 mg L(-1), Zn 26.21 mg L(-1)), respectively. Moreover, the strain ZM130 also exhibited laccase and nicotinamide adenine dinucleotide (reduced)-dichlorophenolindophenol reductase (NADH-DCIP reductase) activity during the decolorization of reactive red-120. However, the laccase activity was found to be maximum in the presence of 300 mg L(-1) of the dye as compared to other concentrations. Hence, the isolation of this strain might serve as a potential bio-resource required for developing the strategies aiming at bioremediation of the wastewater contaminated with dyes and heavy metals.


Subject(s)
Chromium/analysis , Coloring Agents/analysis , Metals, Heavy/analysis , Models, Theoretical , Pseudomonas aeruginosa/growth & development , Textile Industry , Water Pollutants, Chemical/analysis , Water Purification/methods , Azo Compounds/analysis , Biodegradation, Environmental , Laccase/metabolism , Pseudomonas aeruginosa/enzymology , Pseudomonas aeruginosa/isolation & purification , Quinone Reductases/metabolism , RNA, Ribosomal, 16S , Wastewater/chemistry , Wastewater/microbiology
16.
Environ Technol ; 37(16): 2082-7, 2016 Aug.
Article in English | MEDLINE | ID: mdl-26776601

ABSTRACT

The worldwide rising energy demands and the concerns about the sustainability of fossil fuels have led to the search for some low-cost renewable fuels. In this scenario, the production of biodiesel from various vegetable and animal sources has attracted worldwide attention. The present study was conducted to evaluate the production of biodiesel from the oil industry waste following base-catalysed transesterification. The transesterification reaction gave a yield of 83.7% by 6:1 methanol/oil molar ratio, at 60°C over 80 min of reaction time in the presence of NaOH. The gas chromatographic analysis of the product showed the presence of 16 fatty acid methyl esters with linoleic and oleic acid as principal components representing about 31% and 20.7% of the total methyl esters, respectively. The fourier transform infrared spectroscopy spectrum of oil industry waste and transesterified product further confirmed the formation of methyl esters. Furthermore, the fuel properties of oil industry waste methyl esters, such as kinematic viscosity, cetane number, cloud point, pour point, flash point, acid value, sulphur content, cold filter plugging point, copper strip corrosion, density, oxidative stability, higher heating values, ash content, water content, methanol content and total glycerol content, were determined and discussed in the light of ASTM D6751 and EN 14214 biodiesel standards. Overall, this study presents the production of biodiesel from the oil industry waste as an approach of recycling this waste into value-added products.


Subject(s)
Biofuels , Fatty Acids/chemistry , Industrial Waste , Waste Disposal, Fluid/methods , Esterification , Kinetics , Plant Oils/chemistry
17.
Protein Pept Lett ; 22(8): 743-9, 2015.
Article in English | MEDLINE | ID: mdl-26021385

ABSTRACT

In the present study, we reported for the first time the effect of various concentrations (0.5- 3.0 mM) of Mg(2+) and Al(3+) ions on the kinetics and thermodynamics of Aspergillus niger invertases for sucrose hydrolysis. We found that both metal ions enhanced the affinity of invertase for sucrose by decreasing the Km. In the presence of 0.5 mM Al(3+) ions invertase have maximum affinity for sucrose (Km = 0.00914 M sucrose). Invertase was activated by Mg(2+) ions at low concentrations (0.5-2.0 mM) and 341% increase in turnover (Kcat) and maximum decrease in ΔG* was observed in the presence of 0.5 mM Mg(2+) ions. The entropy change for activation of substrate hydrolysis (ΔS*) was increased by all concentrations of Mg(2+) ions and was highest (-94 J mol(-1) K(-1)) for invertases bound with 1.5 mM Mg(2+) ions.


Subject(s)
Aluminum/chemistry , Aspergillus niger/enzymology , Fungal Proteins/chemistry , Fungal Proteins/metabolism , Magnesium/chemistry , beta-Fructofuranosidase/chemistry , beta-Fructofuranosidase/metabolism , Enzyme Stability , Hydrogen-Ion Concentration , Sucrose/metabolism , Thermodynamics
18.
Bioinformation ; 9(18): 901-7, 2013.
Article in English | MEDLINE | ID: mdl-24307767

ABSTRACT

This paper presents an in silico characterization of the chitin binding protein CBP50 from B. thuringiensis serovar konkukian S4 through homology modeling and molecular docking. The CBP50 has shown a modular structure containing an N-terminal CBM33 domain, two consecutive fibronectin-III (Fn-III) like domains and a C-terminal CBM5 domain. The protein presented a unique modular structure which could not be modeled using ordinary procedures. So, domain wise modeling using MODELLER and docking analyses using Autodock Vina were performed. The best conformation for each domain was selected using standard procedure. It was revealed that four amino acid residues Glu-71, Ser-74, Glu-76 and Gln-90 from N-terminal domain are involved in protein-substrate interaction. Similarly, amino acid residues Trp-20, Asn-21, Ser-23 and Val-30 of Fn-III like domains and Glu-15, Ala-17, Ser-18 and Leu-35 of C-terminal domain were involved in substrate binding. Site-directed mutagenesis of these proposed amino acid residues in future will elucidate the key amino acids involved in chitin binding activity of CBP50 protein.

19.
Food Chem ; 130(1)2012 Jan 01.
Article in English | MEDLINE | ID: mdl-24293795

ABSTRACT

Glucoamylases (GAs) from a wild and a deoxy-d-glucose-resistant mutant of a locally isolated Aspergillus niger were purified to apparent homogeneity. The subunit molecular mass estimated by SDS-PAGE was 93 kDa for both strains, while the molecular masses determined by MALDI-TOF for wild and mutant GAs were 72.876 and 72.063 kDa, respectively. The monomeric nature of the enzymes was confirmed through activity staining. Significant improvement was observed in the kinetic properties of the mutant GA relative to the wild type enzyme. Kinetic constants of starch hydrolysis for A. niger parent and mutant GAs calculated on the basis of molecular masses determined through MALDI-TOF were as follows: kcat = 343 and 727 s-1, Km = 0.25 and 0.16 mg mL-1, kcat/Km (specificity constant) = 1374 and 4510 mg mL-1 s-1, respectively. Thermodynamic parameters for soluble starch hydrolysis also suggested that mutant GA was more efficient compared to the parent enzyme.

20.
Protein Pept Lett ; 16(9): 1098-105, 2009.
Article in English | MEDLINE | ID: mdl-19508217

ABSTRACT

Here we report for the first time heat of ionization of invertase (E.C.3.2.1.26) active site residues from hyper-producer strain of Aspergillus niger (34.1 U ml(-1)), along with its physiochemical properties, kinetics and thermodynamics of stability-function. The Invertase showed great potential for industry as being highly efficient (k(cat) = 24167 s(-1) at 65 degrees C, pH 5.0) and stable (half life= 12 h at 56 degrees C).


Subject(s)
Aspergillus niger/enzymology , beta-Fructofuranosidase/chemistry , beta-Fructofuranosidase/genetics , Aspergillus niger/genetics , Catalytic Domain , Chemical Phenomena , Enzyme Stability , Kinetics , Temperature , Thermodynamics , beta-Fructofuranosidase/isolation & purification , beta-Fructofuranosidase/metabolism
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