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1.
J Environ Pathol Toxicol Oncol ; 40(3): 25-35, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34587402

RESUMO

This study is intended to explore the anticancer, antiproliferative, and chemopreventive action of troxerutin (TX) in human non-small-cell lung cancer cell (A549) using BALB/c nude mice. 2 × 106 A549 cells were subcutaneously injected into mice, along with 10 µM and 20 µM/kg body weight of TX orally for 19 days. On the last day, tumor weight and volume were assessed. Stress marker enzymes such as Aryl hydrocarbon hydroxylase (AHH), lactate dehydrogenase (LDH), 5'Nucleotidase (5'ND), and γ-glutamyltranspeptidase (γ-GT) were estimated in the lung tissues. Cytotoxicity of TX was assessed using MTT assay. Expression of carcinoembryonic antigen (CEA) and inflammatory cytokines were also analyzed. Histopathological examination of tissue sections and immunohistochemical examination of proliferating cell nuclear antigen (PCNA) were also performed. mRNA expression of p53, p21, cyclin D1, P13k, Akt, and mTOR were analyzed using RT-PCR. TX administered orally in a dose-dependent manner markedly reverted the level of stress marker enzymes to a significant extent. TX also exhibited significant protection against lung cancer cells, as evidenced by cytotoxicity assay and histopathological studies. It was also found to reduce the expression of PCNA, cyclin D1, P13k, Akt, and mTOR, but increase the expression of p53 and p21. TX has also been shown to reduce cancer cell inflammation, as was evidenced by reduced expression of inflammatory cytokines. Thus TX could be used as an effective chemopreventive and anticancer agent in treating cancer.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Hidroxietilrutosídeo/análogos & derivados , Neoplasias Pulmonares/tratamento farmacológico , Células A549 , Animais , Biomarcadores/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Sobrevivência Celular/efeitos dos fármacos , Enzimas/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Hidroxietilrutosídeo/farmacologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos Endogâmicos BALB C , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Molecules ; 26(15)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34361657

RESUMO

The current review aims to summarise the biodiversity and biosynthesis of novel secondary metabolites compounds, of the phylum Actinobacteria and the diverse range of secondary metabolites produced that vary depending on its ecological environments they inhabit. Actinobacteria creates a wide range of bioactive substances that can be of great value to public health and the pharmaceutical industry. The literature analysis process for this review was conducted using the VOSviewer software tool to visualise the bibliometric networks of the most relevant databases from the Scopus database in the period between 2010 and 22 March 2021. Screening and exploring the available literature relating to the extreme environments and ecosystems that Actinobacteria inhabit aims to identify new strains of this major microorganism class, producing unique novel bioactive compounds. The knowledge gained from these studies is intended to encourage scientists in the natural product discovery field to identify and characterise novel strains containing various bioactive gene clusters with potential clinical applications. It is evident that Actinobacteria adapted to survive in extreme environments represent an important source of a wide range of bioactive compounds. Actinobacteria have a large number of secondary metabolite biosynthetic gene clusters. They can synthesise thousands of subordinate metabolites with different biological actions such as anti-bacterial, anti-parasitic, anti-fungal, anti-virus, anti-cancer and growth-promoting compounds. These are highly significant economically due to their potential applications in the food, nutrition and health industries and thus support our communities' well-being.


Assuntos
Actinobacteria/metabolismo , Antibacterianos/isolamento & purificação , Antibacterianos/metabolismo , Produtos Biológicos , Enzimas/isolamento & purificação , Enzimas/metabolismo , Metabolismo Secundário
3.
Molecules ; 26(16)2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34443529

RESUMO

Insects of the order Hymenoptera have a defensive substance that contains many biologically active compounds. Specifically, venom from honeybees (Apis mellifera) contains many enzymes and peptides that are effective against various diseases. Different research papers stated the possibility of using bee venom (a direct bee sting or in an injectable form) in treating several complications; either in vivo or in vitro. Other reports used the active fractions of bee venom clinically or at labratory scale. Many reports and publications have stated that bee venom and its constituents have multiple biological activities including anti-microbial, anti-protozoan, anti-cancer, anti-inflammatory, and anti-arthritic properties. The present review aims to refer to the use of bee venom itself or its fractions in treating several diseases and counteracting drug toxicities as an alternative protocol of therapy. The updated molecular mechanisms of actions of bee venom and its components are discussed in light of the previous updated publications. The review also summarizes the potential of venom loaded on nanoparticles as a drug delivery vehicle and its molecular mechanisms. Finally, the products of bee venom available in markets are also demonstrated.


Assuntos
Venenos de Abelha/uso terapêutico , Abelhas/química , Enzimas/química , Preparações Farmacêuticas/química , Alérgenos/efeitos adversos , Alérgenos/química , Animais , Venenos de Abelha/química , Venenos de Abelha/enzimologia , Humanos , Mordeduras e Picadas de Insetos , Peptídeos/química , Peptídeos/uso terapêutico
4.
Biomolecules ; 11(7)2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34356667

RESUMO

During the last century, anthropogenic activities such as fertilization have led to an increase in pollution in many ecosystems by nitrogen compounds. Consequently, researchers aim to reduce nitrogen pollutants following different strategies. Some haloarchaea, owing to their denitrifier metabolism, have been proposed as good model organisms for the removal of not only nitrate, nitrite, and ammonium, but also (per)chlorates and bromate in brines and saline wastewater. Bacterial denitrification has been extensively described at the physiological, biochemical, and genetic levels. However, their haloarchaea counterparts remain poorly described. In previous work the model structure of nitric oxide reductase was analysed. In this study, a bioinformatic analysis of the sequences and the structural models of the nitrate, nitrite and nitrous oxide reductases has been described for the first time in the haloarchaeon model Haloferax mediterranei. The main residues involved in the catalytic mechanism and in the coordination of the metal centres have been explored to shed light on their structural characterization and classification. These results set the basis for understanding the molecular mechanism for haloarchaeal denitrification, necessary for the use and optimization of these microorganisms in bioremediation of saline environments among other potential applications including bioremediation of industrial waters.


Assuntos
Proteínas Arqueais/química , Proteínas Arqueais/metabolismo , Enzimas/metabolismo , Haloferax mediterranei/metabolismo , Coenzimas/metabolismo , Simulação por Computador , Desnitrificação , Enzimas/química , Haloferax mediterranei/enzimologia , Modelos Moleculares , Nitrato Redutase/química , Nitrato Redutase/metabolismo , Nitrito Redutases/química , Nitrito Redutases/metabolismo , Oxirredutases/química , Oxirredutases/metabolismo , Sinais Direcionadores de Proteínas , Alinhamento de Sequência
5.
Molecules ; 26(16)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34443378

RESUMO

Ionic liquids have unique chemical properties that have fascinated scientists in many fields. The effects of adding ionic liquids to biocatalysts are many and varied. The uses of ionic liquids in biocatalysis include improved separations and phase behaviour, reduction in toxicity, and stabilization of protein structures. As the ionic liquid state of the art has progressed, concepts of what can be achieved in biocatalysis using ionic liquids have evolved and more beneficial effects have been discovered. In this review ionic liquids for whole-cell and isolated enzyme biocatalysis will be discussed with an emphasis on the latest developments, and a look to the future.


Assuntos
Biocatálise , Células/metabolismo , Enzimas/isolamento & purificação , Líquidos Iônicos/química , Solubilidade
6.
BMC Plant Biol ; 21(1): 361, 2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34364372

RESUMO

BACKGROUND: Priming of seed prior chilling is regarded as one of the methods to promote seeds germination, whole plant growth, and yield components. The application of biostimulants was reported as beneficial for protecting many plants from biotic or abiotic stresses. Their value was as important to be involved in improving the growth parameters of plants. Also, they were practiced in the regulation of various metabolic pathways to enhance acclimation and tolerance in coriander against chilling stress. To our knowledge, little is deciphered about the molecular mechanisms underpinning the ameliorative impact of biostimulants in the context of understanding the link and overlap between improved morphological characters, induced metabolic processes, and upregulated gene expression. In this study, the ameliorative effect(s) of potassium silicate, HA, and gamma radiation on acclimation of coriander to tolerate chilling stress was evaluated by integrating the data of growth, yield, physiological and molecular aspects. RESULTS: Plant growth, yield components, and metabolic activities were generally diminished in chilling-stressed coriander plants. On the other hand, levels of ABA and soluble sugars were increased. Alleviation treatment by humic acid, followed by silicate and gamma irradiation, has notably promoted plant growth parameters and yield components in chilling-stressed coriander plants. This improvement was concomitant with a significant increase in phytohormones, photosynthetic pigments, carbohydrate contents, antioxidants defense system, and induction of large subunit of RuBisCO enzyme production. The assembly of Toc complex subunits was maintained, and even their expression was stimulated (especially Toc75 and Toc 34) upon alleviation of the chilling stress by applied biostimulators. Collectively, humic acid was the best the element to alleviate the adverse effects of chilling stress on growth and productivity of coriander. CONCLUSIONS: It could be suggested that the inducing effect of the pretreatments on hormonal balance triggered an increase in IAA + GA3/ABA hormonal ratio. This ratio could be linked and engaged with the protection of cellular metabolic activities from chilling injury against the whole plant life cycle. Therefore, it was speculated that seed priming in humic acid is a powerful technique that can benefit the chilled along with non-chilled plants and sustain the economic importance of coriander plant productivity.


Assuntos
Resposta ao Choque Frio/fisiologia , Coriandrum/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/farmacologia , Sementes/crescimento & desenvolvimento , Aclimatação , Antioxidantes/metabolismo , Metabolismo dos Carboidratos , Carboidratos/análise , Proteínas de Cloroplastos/metabolismo , Resposta ao Choque Frio/efeitos dos fármacos , Resposta ao Choque Frio/efeitos da radiação , Coriandrum/efeitos dos fármacos , Coriandrum/efeitos da radiação , Enzimas/metabolismo , Raios gama , Substâncias Húmicas , Peroxidação de Lipídeos , Pigmentos Biológicos/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Compostos de Potássio/química , Compostos de Potássio/farmacologia , Sementes/efeitos dos fármacos , Sementes/efeitos da radiação
7.
BMC Plant Biol ; 21(1): 362, 2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34364388

RESUMO

BACKGROUND: The root rot of fragrant solomonseal (Polygonatum odoratum) has occurred frequently in the traditional P. odoratum cultivating areas in recent years, causing a heavy loss in yield and quality. The phenolic acids in soil, which are the exudates from the P. odoratum root, act as allelochemicals that contribute to the consecutive monoculture problem (CMP) of the medicinal plant. The aim of this study was to get a better understanding of P. odoratum CMP. RESULTS: The phenolic acid contents, the nutrient chemical contents, and the enzyme activities related to the soil nutrient metabolism in the first cropping (FC) soil and continuous cropping (CC) soil were determined, and the differentially expressed genes (DEGs) related to the regulation of the phenolic acids in roots were analyzed. The results showed that five low-molecule-weight phenolic acids were detected both in the CC soil and FC soil, but the phenolic acid contents in the CC soil were significantly higher than those in the FC soil except vanillic acid. The contents of the available nitrogen, available phosphorus, and available potassium in the CC soil were significantly decreased, and the activities of urease and sucrase in the CC soil were significantly decreased. The genomic analysis showed that the phenolic acid anabolism in P. odoratum in the CC soil was promoted. These results indicated that the phenolic acids were accumulated in the CC soil, the nutrient condition in the CC soil deteriorated, and the nitrogen metabolism and sugar catabolism of the CC soil were lowered. Meantime, the anabolism of phenolic acids was increased in the CC plant. CONCLUSIONS: The CC system promoted the phenolic acid anabolism in P. odoratum and made phenolic acids accumulate in the soil.


Assuntos
Agricultura/métodos , Hidroxibenzoatos/análise , Polygonatum/genética , Solo/química , Enzimas/análise , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Hidroxibenzoatos/metabolismo , Nitrogênio/análise , Fósforo/análise , Proteínas de Plantas/genética , Plantas Medicinais , Polygonatum/metabolismo , Rizosfera , Análise de Sequência de RNA
8.
Int J Mol Sci ; 22(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34360916

RESUMO

Organophosphorus nerve agents (OPNAs) are highly toxic compounds inhibiting cholinergic enzymes in the central and autonomic nervous systems and neuromuscular junctions, causing severe intoxications in humans. Medical countermeasures and efficient decontamination solutions are needed to counteract the toxicity of a wide spectrum of harmful OPNAs including G, V and Novichok agents. Here, we describe the use of engineered OPNA-degrading enzymes for the degradation of various toxic agents including insecticides, a series of OPNA surrogates, as well as real chemical warfare agents (cyclosarin, sarin, soman, tabun, VX, A230, A232, A234). We demonstrate that only two enzymes can degrade most of these molecules at high concentrations (25 mM) in less than 5 min. Using surface assays adapted from NATO AEP-65 guidelines, we further show that enzyme-based solutions can decontaminate 97.6% and 99.4% of 10 g∙m-2 of soman- and VX-contaminated surfaces, respectively. Finally, we demonstrate that these enzymes can degrade ethyl-paraoxon down to sub-inhibitory concentrations of acetylcholinesterase, confirming their efficacy from high to micromolar doses.


Assuntos
Descontaminação/métodos , Enzimas/química , Inseticidas/química , Agentes Neurotóxicos/química , Compostos Organofosforados/química
9.
Molecules ; 26(16)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34443447

RESUMO

Okara is a soybean transformation agri-food by-product, the massive production of which currently poses severe disposal issues. However, its composition is rich in seed storage proteins, which, once extracted, can represent an interesting source of bioactive peptides. Antimicrobial and antifungal proteins and peptides have been described in plant seeds; thus, okara is a valuable source of compounds, exploitable for integrated pest management. The aim of this work is to describe a rapid and economic procedure to isolate proteins from okara, and to produce an enzymatic proteolyzed product, active against fungal plant pathogens. The procedure allowed the isolation and recovery of about 30% of okara total proteins. Several proteolytic enzymes were screened to identify the proper procedure to produce antifungal compounds. Antifungal activity of the protein digested for 24 h with pancreatin against Fusarium and R. solani mycelial growth and Pseudomonas spp was assessed. A dose-response inhibitory activity was established against fungi belonging to the Fusarium genus. The exploitation of okara to produce antifungal bioactive peptides has the potential to turn this by-product into a paradigmatic example of circular economy, since a field-derived food waste is transformed into a source of valuable compounds to be used in field crops protection.


Assuntos
Antifúngicos/farmacologia , Enzimas/metabolismo , Proteínas de Plantas/metabolismo , Plantas/microbiologia , Polissacarídeos/metabolismo , Liofilização , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Peso Molecular , Proteólise/efeitos dos fármacos , Alimentos de Soja , Espectrofotometria Ultravioleta , Tripsina/metabolismo , Inibidores da Tripsina/farmacologia
10.
Molecules ; 26(16)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34443458

RESUMO

Adverse effects associated with synthetic drugs in diabetes therapy has prompted the search for novel natural lead compounds with little or no side effects. Effects of phenolic compounds from Carpobrotus edulis on carbohydrate-metabolizing enzymes through in vitro and in silico methods were assessed. Based on the half-maximal inhibitory concentrations (IC50), the phenolic extract of the plant had significant (p < 0.05) in vitro inhibitory effect on the specific activity of alpha-amylase (0.51 mg/mL), alpha-glucosidase (0.062 mg/mL) and aldose reductase (0.75 mg/mL), compared with the reference standards (0.55, 0.72 and 7.05 mg/mL, respectively). Molecular interactions established between the 11 phenolic compounds identifiable from the HPLC chromatogram of the extract and active site residues of the enzymes revealed higher binding affinity and more structural compactness with procyanidin (-69.834 ± 6.574 kcal/mol) and 1,3-dicaffeoxyl quinic acid (-42.630 ± 4.076 kcal/mol) as potential inhibitors of alpha-amylase and alpha-glucosidase, respectively, while isorhamnetin-3-O-rutinoside (-45.398 ± 4.568 kcal/mol) and luteolin-7-O-beta-d-glucoside (-45.102 ± 4.024 kcal/mol) for aldose reductase relative to respective reference standards. Put together, the findings are suggestive of the compounds as potential constituents of C. edulis phenolic extract responsible for the significant hypoglycemic effect in vitro; hence, they could be exploited in the development of novel therapeutic agents for type-2 diabetes and its retinopathy complication.


Assuntos
Aizoaceae/química , Diabetes Mellitus Tipo 2/tratamento farmacológico , Retinopatia Diabética/tratamento farmacológico , Simulação de Dinâmica Molecular , Fenóis/análise , Fenóis/uso terapêutico , Animais , Cromatografia Líquida de Alta Pressão , Enzimas/metabolismo , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Simulação de Acoplamento Molecular , Ratos , Suínos , Termodinâmica
11.
Biomolecules ; 11(7)2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34356649

RESUMO

Curcumin is a known anti-adipogenic agent for alleviating obesity and related disorders. Comprehensive comparisons of the anti-adipogenic activity of curcumin with other curcuminoids is minimal. This study compared adipogenesis inhibition with curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcumin (BDMC), and their underlying mechanisms. We differentiated 3T3-L1 cells in the presence of curcuminoids, to determine lipid accumulation and triglyceride (TG) production. The expression of adipogenic transcription factors and lipogenic proteins was analyzed by Western blot. A significant reduction in Oil red O (ORO) staining was observed in the cells treated with curcuminoids at 20 µM. Inhibition was increased in the order of curcumin < DMC < BDMC. A similar trend was observed in the detection of intracellular TG. Curcuminoids suppressed differentiation by downregulating the expression of peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα), leading to the downregulation of the lipogenic enzymes acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS). AMP-activated protein kinase α (AMPKα) phosphorylation was also activated by BDMC. Curcuminoids reduced the release of proinflammatory cytokines and leptin in 3T3-L1 cells in a dose-dependent manner, with BDMC showing the greatest potency. BDMC at 20 µM significantly decreased leptin by 72% compared with differentiated controls. Molecular docking computation indicated that curcuminoids, despite having structural similarity, had different interaction positions to PPARγ, C/EBPα, and ACC. The docking profiles suggested a possible interaction of curcuminoids with C/EBPα and ACC, to directly inhibit their expression.


Assuntos
Adipogenia/efeitos dos fármacos , Diarileptanoides/química , Diarileptanoides/farmacologia , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipogenia/fisiologia , Adipocinas/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Curcuma/química , Curcumina/análise , Curcumina/farmacologia , Enzimas/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Camundongos , Simulação de Acoplamento Molecular , PPAR gama/química , PPAR gama/metabolismo , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Triglicerídeos/metabolismo
12.
Molecules ; 26(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34443339

RESUMO

The treatment of environmental pollution by microorganisms and their enzymes is an innovative and socially acceptable alternative to traditional remediation approaches. Microbial biodegradation is often characterized with high efficiency as this process is catalyzed via degrading enzymes. Various naturally isolated microorganisms were demonstrated to have considerable ability to mitigate many environmental pollutants without external intervention. However, only a small fraction of these strains are studied in detail to reveal the mechanisms at the enzyme level, which strictly limited the enhancement of the degradation efficiency. Accordingly, this review will comprehensively summarize the function of various degrading enzymes with an emphasis on catalytic mechanisms. We also inspect the expanded applications of these pollutant-degrading enzymes in industrial processes. An in-depth understanding of the catalytic mechanism of enzymes will be beneficial for exploring and exploiting more degrading enzyme resources and thus ameliorate concerns associated with the ineffective biodegradation of recalcitrant and xenobiotic contaminants with the help of gene-editing technology and synthetic biology.


Assuntos
Biocatálise , Poluentes Ambientais/metabolismo , Enzimas/metabolismo , Poluentes Ambientais/isolamento & purificação
13.
Nat Commun ; 12(1): 4912, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389721

RESUMO

Polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) hybrid systems typically use complex protein-protein interactions to facilitate direct transfer of intermediates between these multimodular megaenzymes. In the canal-associated neurons (CANs) of Caenorhabditis elegans, PKS-1 and NRPS-1 produce the nemamides, the only known hybrid polyketide-nonribosomal peptides biosynthesized by animals, through a poorly understood mechanism. Here, we use genome editing and mass spectrometry to map the roles of individual PKS-1 and NRPS-1 enzymatic domains in nemamide biosynthesis. Furthermore, we show that nemamide biosynthesis requires at least five additional enzymes expressed in the CANs that are encoded by genes distributed across the worm genome. We identify the roles of these enzymes and discover a mechanism for trafficking intermediates between a PKS and an NRPS. Specifically, the enzyme PKAL-1 activates an advanced polyketide intermediate as an adenylate and directly loads it onto a carrier protein in NRPS-1. This trafficking mechanism provides a means by which a PKS-NRPS system can expand its biosynthetic potential and is likely important for the regulation of nemamide biosynthesis.


Assuntos
Vias Biossintéticas/genética , Proteínas de Caenorhabditis elegans/genética , Peptídeo Sintases/genética , Peptídeos/metabolismo , Policetídeo Sintases/genética , Policetídeos/metabolismo , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/citologia , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Cromatografia Líquida/métodos , Enzimas/genética , Enzimas/metabolismo , Expressão Gênica , Espectrometria de Massas/métodos , Estrutura Molecular , Mutação , Neurônios/metabolismo , Peptídeo Sintases/metabolismo , Peptídeos/química , Policetídeo Sintases/metabolismo , Policetídeos/química
14.
Biosens Bioelectron ; 192: 113494, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34303137

RESUMO

Nanozymes (NZs) are nanomaterials that mimic enzyme-like catalytic activity. They have attracted substantial attention due to their inherent physicochemical properties for use as promising alternatives to natural enzymes (NEs) in a variety of research fields. Particularly, in biosensing and bioassays, NZs have opened a new horizon to eliminate the intrinsic limitations of NEs, including their denaturation at extreme pH values and temperatures, poor reusability and recyclability, and high production costs. Moreover, the catalytic activity of NZs can be modulated in the preparation step by following an appropriate synthesis strategy. This review aims to gain insight into the potential substitution of NEs by NZs in biosensing and bioassays while considering both the pros and cons.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Bioensaio , Catálise , Enzimas
15.
Molecules ; 26(14)2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34299429

RESUMO

Hybrid bioinorganic biocatalysts have received much attention due to their simple synthesis, high efficiency, and structural features that favor enzyme activity and stability. The present work introduces a biomineralization strategy for the formation of hybrid nanocrystals from ß-galactosidase. The effects of the immobilization conditions were studied, identifying the important effect of metal ions and pH on the immobilization yield and the recovered activity. For a deeper understanding of the biomineralization process, an in silico study was carried out to identify the ion binding sites at the different conditions. The selected ß-galactosidase nanocrystals showed high specific activity (35,000 IU/g biocatalyst) and remarkable thermal stability with a half-life 11 times higher than the soluble enzyme. The nanobiocatalyst was successfully tested for the synthesis of galacto-oligosaccharides, achieving an outstanding performance, showing no signs of diffusional limitations. Thus, a new, simple, biocompatible and inexpensive nanobiocatalyst was produced with high enzyme recovery (82%), exhibiting high specific activity and high stability, with promising industrial applications.


Assuntos
Enzimas Imobilizadas/química , Enzimas/química , beta-Galactosidase/química , Sítios de Ligação/fisiologia , Biomineralização/fisiologia , Simulação por Computador , Estabilidade Enzimática , Enzimas/metabolismo , Enzimas Imobilizadas/metabolismo , Galactose/química , Concentração de Íons de Hidrogênio , Nanopartículas/química , Oligossacarídeos/química , Temperatura , beta-Galactosidase/metabolismo
16.
Artigo em Inglês | MEDLINE | ID: mdl-34271192

RESUMO

The acute stress response is well-characterized, with rainbow trout as a teleost model for physiological and molecular responses. Air exposure, which stimulates an acute stress response, modulates liver microRNAs in rainbow trout; however, these highly conserved non-coding RNAs that bind to mRNA and repress translation, have never been measured in brook trout and it is unknown how miRNA expression responds following air exposure in this less studied salmonid. Our objective was to characterize the effects of air exposure on rainbow and brook trout liver miRNA expression, as well as the mRNA expression and enzyme activity that the miRNAs are predicted to target. Brook and rainbow trout were sampled pre- and 1-, 3-, and 24-h post- a three-minute air exposure. Plasma cortisol, glucose, and lactate were measured. Relative expression of miR-21a-5p, miR-143-3p, let-7a-5p and relative expression and enzyme activities of five predicted targets (pyruvate kinase, glucokinase, citrate synthase, cytochrome c oxidase, and catalase) were measured in liver. Rainbow and brook trout both had increases in plasma cortisol and lactate, while only rainbow trout had significant post-stress increases in plasma glucose. Furthermore, both trout species had increased miR-143-3p and miR-21a-5p relative expression 24-h post-stress. Four of the five enzymes measured had altered activity following stress. Brook trout miRNAs had inverse relative expression with relative catalase mRNA expression and cytochrome c oxidase enzyme activity, but no relationship was found in rainbow trout. Therefore, we have further characterized the transcriptional and enzymatic response to air exposure in two salmonids.


Assuntos
Poluentes Atmosféricos/análise , Enzimas/metabolismo , Fígado/metabolismo , MicroRNAs/genética , Oncorhynchus mykiss/metabolismo , RNA Mensageiro/genética , Estresse Fisiológico , Animais , Enzimas/genética , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Oncorhynchus mykiss/genética
17.
Nat Commun ; 12(1): 4461, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34294694

RESUMO

Serial femtosecond crystallography has opened up many new opportunities in structural biology. In recent years, several approaches employing light-inducible systems have emerged to enable time-resolved experiments that reveal protein dynamics at high atomic and temporal resolutions. However, very few enzymes are light-dependent, whereas macromolecules requiring ligand diffusion into an active site are ubiquitous. In this work we present a drop-on-drop sample delivery system that enables the study of enzyme-catalyzed reactions in microcrystal slurries. The system delivers ligand solutions in bursts of multiple picoliter-sized drops on top of a larger crystal-containing drop inducing turbulent mixing and transports the mixture to the X-ray interaction region with temporal resolution. We demonstrate mixing using fluorescent dyes, numerical simulations and time-resolved serial femtosecond crystallography, which show rapid ligand diffusion through microdroplets. The drop-on-drop method has the potential to be widely applicable to serial crystallography studies, particularly of enzyme reactions with small molecule substrates.


Assuntos
Cristalografia por Raios X/métodos , Enzimas/química , Enzimas/metabolismo , Animais , Proteínas Aviárias/química , Proteínas Aviárias/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Biocatálise , Domínio Catalítico , Galinhas , Cristalografia por Raios X/instrumentação , Desenho de Equipamento , Modelos Moleculares , Muramidase/química , Muramidase/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , beta-Lactamases/química , beta-Lactamases/metabolismo
18.
Methods Mol Biol ; 2312: 287-300, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34228297

RESUMO

Artificial metalloenzymes, constructed by incorporating a synthetic catalyst into the internal spaces of a protein scaffold, can perform noncanonical chemical transformations that are not possible using natural enzymes. The addition of cell-permeable modules to artificial metalloenzymes allows for noncanonical catalysis to be implemented as a function of mammalian cells. In this chapter, we describe a protocol for controlling cellular function through a cascade consisting of an artificial metalloenzyme and a gene-circuit engineered via synthetic biology.


Assuntos
Engenharia Celular , Enzimas/metabolismo , Metaloproteínas/metabolismo , Engenharia de Proteínas , Biologia Sintética , Biotina/química , Catálise , Técnicas de Cultura de Células , Enzimas/genética , Regulação Enzimológica da Expressão Gênica , Células HEK293 , Humanos , Metaloproteínas/genética , Estreptavidina/química , Especificidade por Substrato , Transfecção
19.
Sheng Wu Gong Cheng Xue Bao ; 37(7): 2197-2210, 2021 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-34327888

RESUMO

Enzymes and cell factories are the core of industrial biotechnology. They play important roles in various fields such as medicine, chemical industry, food, agriculture, and energy. Usually, natural enzymes and cells need to be engineered to improve the catalytic efficiency, stability and enantioselectivity. Directed evolution makes it possible to rapidly improve the properties of enzymes and cell factories. Sensitive and reliable high-throughput screening approaches are the key for successful and efficient engineering of enzymes and cell factories. In this review, we first summarize the advantages and disadvantages of different screening methods and signal generation strategies as well as their application scope; we then describe the latest advances of ultra-high throughput screening technology applied in the directed evolution of enzymes and cell factories in the past three years. On this basis, we discuss the limiting factors that need to be further improved for high-throughput screening systems and forecast the future development trends of high-throughput screening methods, hoping that researchers in various fields including biotechnology and instrument development can cooperate closely to enhance the reliability and applicability of the high-throughput screening techniques.


Assuntos
Evolução Molecular Direcionada , Ensaios de Triagem em Larga Escala , Biotecnologia , Enzimas , Reprodutibilidade dos Testes
20.
Sheng Wu Gong Cheng Xue Bao ; 37(7): 2256-2271, 2021 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-34327893

RESUMO

The development of biotechnology and the in-depth research on disease mechanisms have led to increased application of enzymes in the treatment of diseases. In addition, enzymes have shown great potential in drug manufacturing, particularly in production of non-natural organic compounds, due to the advantages of mild reaction conditions, high catalytic efficiency, high specificity, high selectivity and few side reactions. Moreover, the application of genetic engineering, chemical modification of enzymes and immobilization technologies have further improved the function of enzymes. This review summarized the advances of using enzymes as drugs for disease treatment or as catalysts for drug manufacturing, followed by discussing challenges, potential solutions and future perspectives on the application of enzymes in the medical and pharmaceutical field.


Assuntos
Biotecnologia , Enzimas , Biocatálise , Catálise , Composição de Medicamentos , Enzimas/metabolismo
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