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1.
Chemosphere ; 249: 126121, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32065994

RESUMO

Metal accumulation in soil could lead to severe damage to plants, animals, and humans. The present work aims to evaluate the effects of nickel (Ni) exposure on Medicago sativa at physiological, biochemical, and transcriptomic levels. Plants were exposed to five increasing concentrations of Ni (0, 50, 150, 250, and 500 mg/kg) for 60 days. Agronomic parameters (fresh and dry matter) and chlorophyll content (Chl) were determined in an alfalfa plant. Chemical analyses were conducted, involving the determination of Ni loads in plants (roots and shoots). Moreover, malondialdehyde accumulation (MDA), glutathione-S-transferase (GST), and peroxidase activities, termed as oxidative stress biomarkers, were measured. The gene expression levels of Prx1C, GST, and phytochelatins (PCs) were determined at different nickel concentrations. Our results showed that Ni concentration in plants increased significantly along with Ni concentration in the soil. Regarding oxidative stress biomarkers, Ni contamination caused an increase in peroxidase and GST activities, with a remarkable accumulation of MDA, especially for the highest Ni concentration (500 mg/kg of Ni). Our data showed also a significant upregulation of Prx1C and GST genes in shoots and roots. The PCs' gene expression was significantly enhanced in response to the different nickel concentrations, suggesting their important role in Ni detoxification in alfalfa plants. Our data provided evidence about the clear toxicity of Ni, an often-underestimated trace element.


Assuntos
Medicago sativa/fisiologia , Níquel/toxicidade , Poluentes do Solo/toxicidade , Animais , Clorofila/metabolismo , Malondialdeído/metabolismo , Medicago sativa/efeitos dos fármacos , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/metabolismo , Peroxidases/metabolismo , Fitoquelatinas/metabolismo , Raízes de Plantas/metabolismo , Solo/química , Poluentes do Solo/metabolismo , Transcriptoma/efeitos dos fármacos
2.
Arch Microbiol ; 202(4): 895-903, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31897538

RESUMO

This study investigated the regulatory role of Rhodopseudomonas palustris RP11 in alleviating TBBPA-induced harmful effects in soybean seedlings. In this study, the characteristics of growth promotion by strain RP11 were studied by analysing 5-aminolevulinic acid (ALA) and indole-3-acetic acid (IAA) production, as well as phosphorus-solubilizing and potassium-solubilizing ability. In the pot culture conditions, we tested whether strain RP11 improved soybean seedlings tolerance against TBBPA by measuring the root length and physiological parameters of the seedlings treated with strain RP11 and different concentration of TBBPA (0, 5, 50, 100, and 1000 mg/kg) together. The results showed that strain RP11 secreted IAA and ALA, and solubilized phosphate and potassium. In pot trials, strain RP11 increased the root length, chlorophyll content, carotenoid content, soluble sugar and protein content of soybean seedlings treated with TBBPA, in comparison with the seedlings treated only with TBBPA. Furthermore, strain RP11 induced the activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), decreased the malondialdehyde (MDA) content in soybean seedlings under TBBPA stress. It was concluded that strain RP11 alleviated TBBPA-induced harmful effects in soybean seedlings by the secretion of IAA and ALA, the accumulation of carotenoid, soluble sugar and soluble protein, and the induction of SOD, CAT and POD as well as nutrient adjustment of phosphorus and potassium levels.


Assuntos
Bifenil Polibromatos/metabolismo , Rodopseudomonas/metabolismo , Plântula/microbiologia , Soja/microbiologia , Catalase/metabolismo , Clorofila/metabolismo , Ácidos Indolacéticos/metabolismo , Malondialdeído/metabolismo , Peroxidase/metabolismo , Peroxidases/metabolismo , Bifenil Polibromatos/toxicidade , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Soja/efeitos dos fármacos , Soja/crescimento & desenvolvimento , Superóxido Dismutase/metabolismo
3.
Proc Natl Acad Sci U S A ; 117(3): 1419-1428, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31896585

RESUMO

By constructing an in vivo-assembled, catalytically proficient peroxidase, C45, we have recently demonstrated the catalytic potential of simple, de novo-designed heme proteins. Here, we show that C45's enzymatic activity extends to the efficient and stereoselective intermolecular transfer of carbenes to olefins, heterocycles, aldehydes, and amines. Not only is this a report of carbene transferase activity in a completely de novo protein, but also of enzyme-catalyzed ring expansion of aromatic heterocycles via carbene transfer by any enzyme.


Assuntos
Biocatálise , Proteínas de Escherichia coli/química , Metano/análogos & derivados , Peroxidases/química , Aldeídos/química , Alcenos/química , Aminas/química , Escherichia coli , Proteínas de Escherichia coli/metabolismo , Metano/química , Peroxidases/metabolismo , Especificidade por Substrato
4.
Nat Commun ; 11(1): 190, 2020 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-31929512

RESUMO

Exercise is among the most effective interventions for age-associated mobility decline and metabolic dysregulation. Although long-term endurance exercise promotes insulin sensitivity and expands respiratory capacity, genetic components and pathways mediating the metabolic benefits of exercise have remained elusive. Here, we show that Sestrins, a family of evolutionarily conserved exercise-inducible proteins, are critical mediators of exercise benefits. In both fly and mouse models, genetic ablation of Sestrins prevents organisms from acquiring metabolic benefits of exercise and improving their endurance through training. Conversely, Sestrin upregulation mimics both molecular and physiological effects of exercise, suggesting that it could be a major effector of exercise metabolism. Among the various targets modulated by Sestrin in response to exercise, AKT and PGC1α are critical for the Sestrin effects in extending endurance. These results indicate that Sestrin is a key integrating factor that drives the benefits of chronic exercise to metabolism and physical endurance.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas de Drosophila/metabolismo , Exercício Físico/fisiologia , Proteínas de Choque Térmico/metabolismo , Oxirredutases/metabolismo , Peroxidases/metabolismo , Animais , Proteínas de Ciclo Celular/genética , Diferenciação Celular , Drosophila , Proteínas de Drosophila/genética , Metabolismo Energético , Expressão Gênica , Proteínas de Choque Térmico/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fibras Musculares Esqueléticas/citologia , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Biogênese de Organelas , Oxirredutases/genética , Peroxidases/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Resistência Física/genética , Resistência Física/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
5.
Chemosphere ; 243: 125318, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31995862

RESUMO

Increased agricultural intensification goes with the widespread use of herbicides that adversely affect aquatic biodiversity. The effects of herbicides on toxin-producing cyanobacteria have been poorly studied. The present study aimed to investigate the toxicological and physiological effects of the herbicide clethodim on Raphidiopsis raciborskii (a.k.a. Cylindrospermopsis raciborskii) ITEPA1 and Microcystis aeruginosa BCCUSP232. On day four of the experiment, the exposure to 25 mg/L clethodim resulted in the highest cell density of R. raciborskii. Similarly, exposure to the 1, 5, 20, and 50 mg/L clethodim treatments resulted in the highest cell densities of M. aeruginosa on day 4 of the experiment. Medium effect concentrations (EC50) after 96 h of exposure of both strains to clethodim were 192.98 mg/L and 168.73 mg/L for R. raciborskii and M. aeruginosa, respectively. The presence of clethodim significantly increased the total microcystin content of M. aeruginosa compared to the control cultures. At 400 mg/L, total saxitoxins content of R. raciborskii was 27% higher than that of the control cultures on day 4. In contrast, cultures exposed to 100 mg/L clethodim had the lowest saxitoxins levels per cell quota. There was an increase in the levels of intracellular hydrogen peroxide in both species during exposure to clethodim, which was followed by significant changes (p < 0.05) in the activity of antioxidant enzymes such as peroxidase and superoxide dismutase. These results revealed that the presence of low levels of clethodim in the aquatic environment might lead to the excessive proliferation of cyanobacteria and alteration of their cyanotoxins content.


Assuntos
Cicloexanonas/farmacologia , Cylindrospermopsis/efeitos dos fármacos , Cylindrospermopsis/crescimento & desenvolvimento , Microcystis/efeitos dos fármacos , Microcystis/crescimento & desenvolvimento , Antioxidantes/metabolismo , Toxinas Bacterianas/metabolismo , Cylindrospermopsis/metabolismo , Herbicidas/farmacologia , Microcistinas/metabolismo , Microcystis/metabolismo , Peroxidases/metabolismo , Saxitoxina/metabolismo , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/farmacologia
6.
Food Microbiol ; 87: 103389, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31948630

RESUMO

To overcome the deleterious effects of hydrogen peroxide, Lactobacillus plantarum elicits an adaptive response to oxidative stress. In this study, global transcriptomic analysis revealed that L. plantarum CAUH2 expanded its carbon source utilizing profile and enhanced glycolysis to produce more ATP to confront with H2O2 stress. Some antioxidant enzymes including NADH peroxidase, thioredoxin reductase and glutathione peroxidase were 6.11, 36.76 and 6.23-fold up-regulated at transcription level for H2O2 scavenging. Meanwhile, free ferrous iron (Fe2+) was maintained at low concentrations in the cytoplasm, which could limit Fenton reaction and reduce the production of hydroxyl radicals. To repair DNA lesion caused by H2O2, both base excision repair system and recombinational DNA repair pathway were employed by L. plantarum CAUH2. In addition, the expression of methionine sulfoxide reductases and thioredoxin were up-regulated to repair oxidized proteins. It is noteworthy that some transcriptional regulators (Spx, CcpA and MarR1) were predicted to participate in the adaptive response to H2O2 stress, suggesting that L. plantarum CAUH2 utilized a wide array of sensors to monitor oxidative stress and modulated the transcriptional regulation network under H2O2 stress. These findings provide novel insight into the protective mechanisms developed by L. plantarum to cope with oxidative stress.


Assuntos
Proteínas de Bactérias/genética , Peróxido de Hidrogênio/farmacologia , Lactobacillus plantarum/efeitos dos fármacos , Lactobacillus plantarum/genética , Proteínas de Bactérias/metabolismo , Perfilação da Expressão Gênica , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Lactobacillus plantarum/enzimologia , Lactobacillus plantarum/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peroxidases/genética , Peroxidases/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo , Transcriptoma/efeitos dos fármacos
7.
J Colloid Interface Sci ; 559: 313-323, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31675662

RESUMO

Antibiotic resistance is a common phenomenon observed during treatment with antibacterials. Use of nanozymes, especially those with synergistic enzyme-like activities, as antibacterials could overcome this problem, but their synthesis is limited by their high cost and/or complex production process. Herein, vanadium oxide nanodots (VOxNDs) were prepared via a one-step bottom-up ethanol-thermal method using vanadium trichloride as the precursor. VOxNDs alone possess bienzyme mimics of peroxidase and oxidase. Accordingly, highly efficient antibacterials against drug-resistant bacteria can be obtained through synergistic catalysis; the oxidase-like activity decomposes O2 to generate superoxide anion radical (O2-) and hydroxyl radicals (OH), and the intrinsic peroxidase-like activity can further induce the production of OH from external H2O2. Consequently, H2O2 concentration could decrease up to four magnitude orders with VOxNDs to achieve an antibacterial efficacy similar to that of H2O2 alone. Wound healing in vivo further confirms the high antibacterial efficiency, good biocompatibility, and application potential of the synergistic antibacterial system due to the "nano" structure of VOxNDs. The method of synthesis of nanodot antibacterials described in this paper is inexpensive, and the results of this study reveal the multi-enzymatic synergism of nanozymes.


Assuntos
Antibacterianos/química , Nanopartículas Metálicas/química , Óxidos/química , Compostos de Vanádio/química , Cicatrização/efeitos dos fármacos , Animais , Materiais Biocompatíveis/química , Materiais Biomiméticos/química , Catálise , Sobrevivência Celular/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Células HeLa , Células Endoteliais da Veia Umbilical Humana , Humanos , Peróxido de Hidrogênio/química , Radical Hidroxila/química , Peroxidases/metabolismo , Ratos Sprague-Dawley , Staphylococcus aureus/efeitos dos fármacos
8.
Chemosphere ; 238: 124572, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31422312

RESUMO

The wastewaters from distilleries of winemaking by-products, a scarcely studied type of vinasse, were treated by white-rot fungal strains from species Irpex lacteus, Ganoderma resinaceum, Trametes versicolor, Phlebia rufa and Bjerkandera adusta. The main objectives of this study were to evaluate fungal performance during vinasse biodegradation, their enzyme patterns and ecotoxicity evolution throughout treatment. Despite all strains were able to promote strong (>80%) dephenolization and reduction of total organic carbon (TOC), P. rufa was less affected by vinasse toxicity and exhibit better decolorization. In batch cultures at 28 °C and pH 4.0, the first phase of P. rufa biodegradation kinetics was characterized by strong metabolic activity with simultaneous depletion of TOC, phenolics and sugars. The main events of second phase are the increase of peroxidases production after the peak of laccase activity, and strong color removal. At the end of treatment, it was observed highly significant (p < 0.001) abatement of pollution parameters (83-100% removal). Since water reclamation and reuse for e.g. crop irrigation is a priority issue, vinasse ecotoxicity was assessed with bioindicators representing three different phylogenetic and trophic levels: a marine bacterium (Aliivibrio fischeri), a freshwater microcrustacean (Daphnia magna) and a dicotyledonous macrophyte (Lepidium sativum). It was observed significant (p < 0.05) reduction of initial vinasse toxicity, as evaluated by these bioindicators, deserving special mention an almost complete phytotoxicity elimination.


Assuntos
Aliivibrio fischeri/crescimento & desenvolvimento , Coriolaceae/metabolismo , Daphnia/crescimento & desenvolvimento , Lepidium sativum/crescimento & desenvolvimento , Polyporales/metabolismo , Trametes/metabolismo , Águas Residuárias/química , Águas Residuárias/toxicidade , Aliivibrio fischeri/metabolismo , Animais , Biodegradação Ambiental , Daphnia/metabolismo , Destilação , Biomarcadores Ambientais/efeitos dos fármacos , Lacase/metabolismo , Lepidium sativum/metabolismo , Peroxidases/metabolismo , Fenóis/metabolismo , Filogenia
9.
Arch Biochem Biophys ; 680: 108231, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31877266

RESUMO

The thioredoxin system plays a central role in intracellular redox regulation and its dysregulation is associated with a number of pathologies. However, the connectivity within this system poses a significant challenge for quantification and consequently several disparate measures have been used to characterize the system. For in vitro studies, the thioredoxin system flux has been measured by NADPH oxidation while the thioredoxin redox state has been used to estimate the activity of the system in vivo. The connection between these measures has been obscure although substrate saturation in the thioredoxin system results from the saturation of the thioredoxin redox cycle. We used computational modeling and in vitro kinetic assays to clarify the relationship between flux and the current in vivo measures of the thioredoxin system together with a novel measure, the thioredoxin redox charge (reduced thioredoxin/total thioredoxin). Our results revealed that the thioredoxin redox potential and redox charge closely tracked flux perturbations showing that these indices could be used as surrogate measures of the flux in vivo and, provide a mechanistic explanation for the previously observed correlations between thioredoxin oxidation and certain pathologies. While we found no significant difference in the linear correlations obtained for the thioredoxin redox potential and redox charge with the flux, the redox charge may be preferred because it is bounded between zero and one and can be determined over a wider range of conditions allowing for quantitative flux comparisons between cell types and conditions.


Assuntos
Proteínas de Membrana/metabolismo , Peroxirredoxinas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Cinética , Modelos Biológicos , NADP/metabolismo , Oxirredução , Peroxidases/metabolismo , Tiorredoxina Redutase 1/metabolismo
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117412, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31357051

RESUMO

Molybdenum dichalcogenides MoX2 (X=S, Se) have been found to possess intrinsic peroxidase-like activity. However, molybdenum oxides (MoO2) as peroxidase mimetics have not been exploited yet. Herein, MoO2 nanoparticles were synthesized by a simple hydrothermal method and found to possess the peroxidase-like activity for the first time. MoO2 nanoparticles could catalyze the oxidation of 3,3',5,5'-tetrametylbenzidine (TMB) by H2O2 to produce a blue-color product (oxTMB). The catalytic property and mechanism were investigated by stead-state kinetics experiment and free radicals scavenging experiment, respectively. Acetylcholinesterase (AChE) could catalyze the hydrolysis of acetylthiocholine chloride (ATCh) into thiocholine (TCh), which could reduce oxTMB to decrease the absorbance in solution. In the presence of AChE inhibitor tacrine, the generation of TCh was inhibited and the absorbance was preserved. Based on these properties, a colorimetric assay method was developed for AChE inhibitor tacrine. This work not only broadens the application of the peroxidase mimetics, but also overcome the disadvantages of traditional methods such as expensive, complex and vulnerable to background interference for colorimetric assay of AChE inhibitor.


Assuntos
Inibidores da Colinesterase/análise , Colorimetria/métodos , Nanopartículas Metálicas/química , Molibdênio/química , Óxidos/química , Tacrina/análise , Inibidores da Colinesterase/metabolismo , Cinética , Nanopartículas Metálicas/análise , Molibdênio/análise , Molibdênio/metabolismo , Óxidos/análise , Óxidos/metabolismo , Peroxidases/metabolismo , Tacrina/metabolismo
11.
Food Chem ; 309: 125759, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31706672

RESUMO

The effects of exogenous spermidine and dicyclohexylamine (DCHA, spermidine synthesis inhibitor) on the antioxidative system and energy status of germinating mung bean were investigated. Results showed that exogenous spermidine increased the content of total phenolic and ascorbic acid and the antioxidative activity, but reduced activities and gene expressions of peroxidase (POD) and catalase (CAT). These changes might be explained by increased H2O2 content and activities of succinic dehydrogenase (SDH), adenosine triphosphatases (ATPases), and cytochrome c oxidase (CCO), resulting in higher adenosine triphosphate (ATP) and energy charge (EC). Interestingly, spermidine down-regulated expressions of SDH, H+-ATPase, Ca2+-ATPase and CCO whilst DCHA reduced energy metabolism and induced the opposite effects to spermidine, except for ascorbic acid content. Inhibition was reversed by exogenous spermidine. In conclusion, spermidine induced the accumulation of H2O2, enhanced the antioxidative system and improved the energy metabolism to enhance the functional quality of mung bean sprouts.


Assuntos
Antioxidantes/química , Metabolismo Energético/efeitos dos fármacos , Espermidina/farmacologia , Vigna/química , Trifosfato de Adenosina/metabolismo , Antioxidantes/metabolismo , Catalase/metabolismo , Cicloexilaminas/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Germinação/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Peroxidases/metabolismo , Superóxido Dismutase/metabolismo , Vigna/crescimento & desenvolvimento , Vigna/metabolismo
12.
Cell Mol Biol (Noisy-le-grand) ; 65(7): 46-54, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31880517

RESUMO

Drought is important abiotic stress that negatively influences the growth and development of plants. Strong efforts are currently ongoing worldwide to improve olive production under adverse environmental conditions by extending genetic diversity to improve key agro-physiological and biochemical features through various breeding programs. This research was performed to evaluate the effect of drought stress on the changes of some physiological and biochemical traits in 20 commercial and promising olive genotypes under field conditions during 2015-2017. Fruit oil content as well as some of physiological traits and antioxidant activities under control and drought stress conditions were evaluated. The results of combined analysis of variance (ANOVA) for fruit yield and other measured traits showed that year, irrigation treatments, genotype main effects and their interactions were highly significant. In general, fruit yield, relative water content (RWC), oil content and total soluble proteins (TPs) showed a decreasing trend, whereas the electrolyte leakage, H2O2 content and activity of catalase (CAT), ascorbate peroxidase (APX) and peroxidase (POX) displayed an increasing trend in the tested olive genotypes during drought stress. A Principal component analysis (PCA)-based biplot demonstrated that stress tolerance index (STI) positively correlated with POX and TPs. Results also revealed a high level of genetic diversity in the tested olive genotypes, and among them, two commercial (Abou-satl) and promising genotypes (T2) responded better to drought by marinating a good balance for fruit yield and some of the antioxidant activities. These genotypes could be used in future programs to develop new olive cultivars with beneficial stress-adaptive traits.


Assuntos
Antioxidantes/metabolismo , Secas , Olea/metabolismo , Ascorbato Peroxidases/metabolismo , Catalase/metabolismo , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Peroxidases/metabolismo , Superóxido Dismutase/metabolismo
13.
Chem Commun (Camb) ; 55(93): 14074-14077, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31696869

RESUMO

We discovered that the function of cytochrome C can be modulated by DNA nanoribbons. Meanwhile, the interplay between the DNA nanoribbons and the native cytochrome C and the possible mechanisms are also discussed.


Assuntos
Citocromos c/metabolismo , DNA/metabolismo , Nanoestruturas/química , Peroxidases/metabolismo , Animais , Catálise , Citocromos c/química , DNA/química , Guaiacol/química , Cavalos , Oxirredução , Peroxidases/química , Ligação Proteica
14.
Environ Sci Pollut Res Int ; 26(36): 36857-36868, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31745795

RESUMO

Gaseous formaldehyde removal efficiency and physiological characteristics of leaves were investigated through a dynamic fumigation system. Three different species of potted Chlorophytum Comosum, (Green Chlorophytum Comosum for its green leaves), CC (Combined the leaves of Chlorophytum Comosum with leaves half green and half white) and PC (Purple Chlorophytum Comosum for its purple leaves), were exposed to formaldehyde for 7 days. The results showed formaldehyde removal efficiencies in the daytime were 71.07% ± 0.23, 84.66% ± 0.19, and 46.73% ± 0.15 at 1 ppm for GC, CC, and GC plants, respectively, and were 36.21% ± 0.24, 62.15% ± 0.19, and 34.97% ± 0.11 at night. This might be due to higher plant physiological activities (e.g., photosynthesis, respiration, and transpiration) during the daytime than at night. Ten physiological indicators of leaves were chosen to evaluate the 7-day fumigation process, which were chlorophyll, free protein, relative conductivity, malondialdehyde (MDA), hydrogen peroxide (H2O2), hydroxyl radical, superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and total antioxidant capacity (T-AOC). Eight of these indicators increased, while chlorophyll decreased by 22.16%, 6.95%, and 25.32%, and CAT decreased by 18.9%, 17.8%, and 25.30% for GC, CC, and PC respectively. Among all the increasing physiological indicators, relative conductivity and MDA showed the greatest increase by 279.32% and 155.56% for PC. A 15-day recovery study was also conducted using MDA and T-AOC as indicators. The results showed that all the tested plants could be tolerant up to the 8 ppm of formaldehyde concentration for 7 days under dynamic fumigation and needed 10-15 days for self-recovery.


Assuntos
Asparagaceae/fisiologia , Biodegradação Ambiental , Formaldeído/metabolismo , Antioxidantes/metabolismo , Catalase/metabolismo , Clorofila/metabolismo , Fumigação , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Peroxidases/metabolismo , Fotossíntese , Folhas de Planta/metabolismo , Plantas/metabolismo , Superóxido Dismutase/metabolismo
15.
J Photochem Photobiol B ; 201: 111679, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31710926

RESUMO

Plants from the family Droseraceae, especially Drosera sp. and Dionaea sp., are naturally rich in phenolic derivatives such as plumbagin, among others. Plumbagin is known both for its pharmacological significance and its protective properties against light stress. Light stress - high light intensity or/and light spectral composition - activates plants' response mechanisms including, among others, hormonal (salicylic acid, jasmonic acid) pathways and secondary metabolite (phenolic compounds, proline) pathways. Short-wavelength radiation, due to its high energy, will induce the synthesis of protective secondary metabolites, including those with pharmaceutical properties. The aim of the study was to describe and compare acclimation strategies of Drosera peltata and Dionaea muscipula to blue-red light in the context of phenolic compound accumulation, and salicylic acid, jasmonic acid and proline synthesis. For the first time, differences in the responses of D. muscipula and D. peltata to blue-red light (in the ratio 6:1) were established. In Dionaea sp., it was associated with the use of redox equivalents (in particular, plastoquinone pool) for the synthesis of primary metabolites used in the process of growth and development. In Drosera sp., a rapid adjustment of redox state led to the synthesis of secondary metabolites, constituting a reservoir of carbon skeletons and allowing for a quick defence response to stress factors. In both species, blue-red light did not induce the jasmonic acid pathway. However, the salicylic acid pathway was induced as an alternative to the phenolic compound synthesis pathway. Nevertheless, the applied blue-red light was not an effective elicitor of phenolic compounds in the plants examined.


Assuntos
Droseraceae/efeitos da radiação , Luz , Fenóis/metabolismo , Catalase/metabolismo , Clorofila/química , Droseraceae/química , Droseraceae/metabolismo , Peroxidação de Lipídeos , Malondialdeído/análise , Peroxidases/metabolismo , Fenóis/química , Prolina/química
16.
BMC Plant Biol ; 19(1): 502, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730480

RESUMO

BACKGROUND: Selenium (Se) is a beneficial element for higher plants and essential for mammals. To study the effect of the foliar application of sodium selenate on fragrant rice performance, a pot experiment was conducted in Guangdong, China. At the initial heading stage, one-time foliar application of sodium selenate with concentrations of 0, 10, 20, 30, 40 and 50 µmol·L- 1 (named CK, Se1, Se2, Se3, Se4 and Se5, respectively) were foliar applied on two fragrant rice varieties, 'Meixiangzhan-2' and 'Xiangyaxiangzhan'. RESULTS: Selenate application at the initial heading stage not only improved the grain yield of fragrant rice by increasing the seed-setting rate and grain weight, but also promoted the grain quality by increasing crude protein contents and lowering the chalky rice rate. Furthermore, Se applications enhanced the biosynthesis of 2-acetyl-1- pyrroline (2-AP), the main aromatic compound, by increasing the contents of precursors (△1- pyrroline, proline and pyrroline-5-carboxylic acid (P5C)) and the activities of enzymes (proline dehydrogenase (PRODH), △1-pyrroline-5-carboxylic acid synthetase (P5CS), and ornithine aminotransferase (OAT)) in fragrant rice. The results also showed that foliar application of sodium selenate enhanced the antioxidant system of both varieties by promoting the activities of peroxidase (POD), superoxide dismutase (SOD), catalase (CAT) and reducing the contents of malondialdehyde (MDA). Furthermore, the real-time PCR analyses depicted that foliar application of selenate up-regulated the GPX1, GPX4 and CATC transcripts. The higher antioxidative enzymatic activities might strength the stress resistant to ensure the stability of yield in fragrant rice form abiotic stress. CONCLUSIONS: Foliar applications of sodium selenate at the initial heading stage increased the grain 2-AP content by enhancing the biosynthesis-related enzymes and precursors. The grain yield and quality of fragrant rice also increased due to selenate application. Furthermore, foliar application of selenate promoted the activities of enzymes such as POD, SOD and CAT and up-regulated the expression of gene GPX4, GPX1 and CATC.


Assuntos
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Oryza/efeitos dos fármacos , Pirróis/metabolismo , Ácido Selênico/administração & dosagem , Antioxidantes/metabolismo , Biomassa , Catalase/metabolismo , Grão Comestível/efeitos dos fármacos , Grão Comestível/enzimologia , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Malondialdeído/metabolismo , Oryza/enzimologia , Oryza/genética , Oryza/crescimento & desenvolvimento , Peroxidases/metabolismo , Proteínas de Plantas/metabolismo , Prolina/metabolismo , Superóxido Dismutase/metabolismo
17.
Comput Biol Chem ; 83: 107136, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31630014

RESUMO

Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (Mtb). In the present age, due to the rapid increase in antibiotic resistance worldwide, TB has become a major threat to human life. Regardless of significant efforts have been inclined to improve the healthcare systems for improving diagnosis, treatment, and anticipatory measures controlling TB is challenging. To date, there are no such therapeutic chemical agents available to fight or control the bacterial drug-resistance. The catalase-peroxidase enzyme (katG) which encoded by the katG gene of Mtb is most frequently getting mutated and hence promotes Isoniazid resistance by diminishing the normal activity of katG enzyme. In the current study, an effort has been intended to find novel and therapeutically active antibacterial chemical compounds through pharmacoinformatics methodologies. Initially, the five mutant katG were generated by making mutation of Ser315 by Thr, Ile, Arg, Asn, and Gly followed by structural optimizations. About eight thousand small molecules were collected from the Asinex antibacterial library. All molecules were docked to active site of five mutant katG and wild type katG. To narrow down the chemical space several criteria were imposed including, screening for highest binding affinity towards katG proteins, compounds satisfying various criterion of drug-likeliness properties like Lipinski's rule of five (RO5), Veber's rule, absorption, distribution, metabolism, and excretion (ADME) profile, and synthetic accessibility. Finally, five molecules were found to be important antibacterial katG inhibitors. All the analyzed parameters suggested that selected molecules are promising in nature. Binding interactions analysis revealed that proposed molecules are efficient enough to form a number of strong binding interactions with katG proteins. Dynamic behavior of the proposed molecules with katG protein was evaluated through 100 ns molecular dynamics (MD) simulation study. Parameters calculated from the MD simulation trajectories adjudged that all molecules can form stable complexes with katG. High binding free energy of all proposed molecules definitely suggested strong affection towards the katG. Hence, it can be concluded that proposed molecules might be used as antibacterial chemical component subjected to experimental validation.


Assuntos
Antituberculosos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/enzimologia , Peroxidases/antagonistas & inibidores , Antituberculosos/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Inibidores Enzimáticos/química , Humanos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Peroxidases/genética , Peroxidases/metabolismo
18.
BMC Genomics ; 20(1): 758, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31640549

RESUMO

BACKGROUND: The mesocotyl connects the coleoptilar node and the basal part of the seminal root of maize (Zea mays) seedling. The mesocotyl pushes the shoot of the seedling out of the soil during seed germination; thus, its growth is highly related to deep-sowing tolerance. Although many studies on the maize mesocotyl have been carried out at physiological and molecular levels, the proteomic changes associated with cellular and physiological activities during mesocotyl growth are still unknown. RESULTS: In the present study, the maize hybrid Zhengdan 958 was used to study mesocotyl growth and accompanying protein changes. The dark-grown etiolated mesocotyls exhibited a slow-fast-slow feature, with significant changes in the levels of indole-3-acetic acid (IAA) and cellulose and the activity of peroxidase (POD). In particular, POD activity increased with mesocotyl growth, showing higher activity at the mature (lower) end of the mesocotyl. For the proteomic analysis, soluble proteins were extracted from etiolated mesocotyls dark-grown for 48 h, 84 h, and 132 h, corresponding to the initial, rapid, and slow growth periods, respectively, and subjected to separation by two-dimensional gel electrophoresis (2-DE). As a result, 88 differentially abundant proteins (DAPs) were identified using MALDI-TOF-TOF analysis. At 48 h, most DAPs were stress proteins, heat shock proteins and storage proteins; at 84 h, oxidation/reduction proteins, carbohydrate biogenesis-related proteins and cytoskeleton-related proteins were highly accumulated; at 132 h, the most striking DAPs were those involved in the synthesis and modification of the cell wall and the biogenesis of carbohydrates. Gene ontology (GO) analysis showed that changes in the abundance and proportion of DAPs were consistent with cellular and physiological activities and biological processes during mesocotyl growth. The accumulation of nine DAPs of interest was verified by immunoblotting and RT-qPCR. CONCLUSIONS: The present study revealed that the protein patterns in 2-D gels differed greatly with mesocotyl growth. At different growth periods, a specific set of DAPs participate in various biological processes and underlie the cellular and physiological activities of the mesocotyl. These results contributed to the understanding of mesocotyl growth and the cultivation of maize lines with deep-sowing tolerance.


Assuntos
Proteínas de Plantas/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Zea mays , Agricultura , Celulose/metabolismo , Eletroforese em Gel Bidimensional , Estiolamento , Ácidos Indolacéticos/metabolismo , Peroxidases/metabolismo , Proteínas de Plantas/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Proteômica , RNA Mensageiro/metabolismo , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo
19.
Genes (Basel) ; 10(9)2019 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-31514481

RESUMO

Pleurotus tuoliensis is a precious edible fungus with extremely high nutritive and medicinal value. The cultivation period of P. tuoliensis is longer than those of other Pleurotus species, which is mainly due to a longer mycelium physiological maturation period (30-60 days). Currently, the molecular processes underlying physiological maturation of the mycelium remain unclear. We performed a comparative transcriptomic analysis of immature and mature mycelia using RNA-seq. De novo transcriptome assembly resulted in identification of 17,030 unigenes. 451 differentially expressed genes-including those encoding nucleoside diphosphate kinase (NDPK), glycoside hydrolase family proteins, exopolygalacturonase, and versatile peroxidases-were identified. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses revealed that nucleotide synthesis and energy metabolism are highly active during the physiological maturation of mycelia, and genes related to these pathways were significantly upregulated in mature mycelia. NDPK is predicted to be essential for mycelia maturation. Our findings contribute to a comprehensive understanding of mycelia maturation in a commercially important fungal species. Future efforts will focus on the function of NDPK and the mechanism by which it regulates mycelia maturation.


Assuntos
Micélio/genética , Pleurotus/genética , Transcriptoma , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Micélio/crescimento & desenvolvimento , Núcleosídeo-Difosfato Quinase/genética , Núcleosídeo-Difosfato Quinase/metabolismo , Peroxidases/genética , Peroxidases/metabolismo , Pleurotus/crescimento & desenvolvimento
20.
Environ Pollut ; 255(Pt 1): 113149, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31522007

RESUMO

Antibiotics have been widely detected in the ocean and have various impacts on the environment, while knowledge of their chronic influence on phytoplankton, especially red tide algae, is still limited. Dinoflagellates and green algae are common phytoplankton in marine ecosystems. The former is the main red tide algae, and the latter is an important primary producer. We investigated the long-term responses of two representative algae, Prorocentrum lima and Chlorella sp., to two common antibiotics (sulfamethoxazole (SMX) and norfloxacin (NFX)) at environmentally relevant levels (10 and 100 ng/L) during simulated natural conditions. The cell density and activities of three antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD)) were analyzed. The results showed that the influence of each antibiotic on Chlorella sp. was not significant (p > 0.05) during the first 10 days, but the influence of the antibiotics later began to show significant inhibition (p < 0.05) compared with the control group, especially during mixed exposure. P. lima was not inhibited, but its cell density increased. SMX had a superior stimulation effect on P. lima. The three enzymes activities of P. lima increased, and the antioxidant mechanism was not seriously impacted. However, for Chlorella sp., the activity of SOD increased while the activities of CAT and POD decreased, suggesting that this algae's antioxidant system was unbalanced due to oxidative stress. Based on our results, the growth of P. lima was different from green algae Chlorella sp. as well as other inhibited marine algae (such as diatom, golden algae) studied in previous studies. Therefore, as a typical pollutant in the ocean, antibiotics may play a positive role in the bloom of dinoflagellate red tides.


Assuntos
Antibacterianos/farmacologia , Chlorella/efeitos dos fármacos , Dinoflagelados/efeitos dos fármacos , Proliferação Nociva de Algas/efeitos dos fármacos , Norfloxacino/farmacologia , Sulfametoxazol/farmacologia , Poluentes da Água/farmacologia , Antioxidantes/metabolismo , Catalase/metabolismo , Chlorella/metabolismo , Dinoflagelados/metabolismo , Ecossistema , Peroxidase/metabolismo , Peroxidases/metabolismo , Superóxido Dismutase/metabolismo , Fatores de Tempo
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