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1.
Postepy Biochem ; 65(2): 128-134, 2019 06 06.
Artigo em Polonês | MEDLINE | ID: mdl-31642651

RESUMO

During leaf senescence and fruit ripening chlorophyll is broken down into nonfluorescent catabolites (NCCs). The chlorophyll degradation pathway includes a series of biochemical transformations ocurring sequentially in chloroplasts, cytosol and vacuoles. The path begins with enzymatic reduction of chlorophyll b to chlorophyll a. Next, the specific dechelatase and esterase remove the magnesium atom and the phytol chain resulting in the formation of pheophorbide a. In the next step, the porphyrin macroring is opened by pheophorbide a oxygenase and red catabolite reductase. The product of this transformation is an early fluorescent catabolite (pFCC), which after hydroxylation and species-specific modifications is imported into the vacuole. In acidic medium of the vacuole pFCC undergo isomerization to their respective colorless NCCs, which are final chlorophyll degradation products in higher plants. There are still no answers to a number of questions about the fate and significance of millions tons of chlorophyll catabolites released annually in the aquatic environment as a result of cellular senescence and death of phytoplankton. A few reports indicate that algae and cyanobacteria may metabolize their photosynthetic pigments in a similar way as higher plants do, however, the course of chlorophyll breakdown in these organisms has not been yet elucidated.


Assuntos
Clorofila/metabolismo , Células Vegetais/metabolismo , Oxirredutases/metabolismo , Células Vegetais/enzimologia , Folhas de Planta/enzimologia , Folhas de Planta/metabolismo
2.
J Agric Food Chem ; 67(42): 11607-11615, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31560536

RESUMO

ζ-carotene desaturase (ZDS) is a key enzyme in carotenoid biosynthesis and plays an important role in plant photosynthesis. We characterized an albino leaf-color mutant obtained from ethyl methanesulfonate treatment: albino and seedling lethality 1 (ale1). The material contains a chloroplast thylakoid defect where photosynthetic pigments declined and reactive oxygen species accumulated resulting in ale1 death within 3 weeks. Positional cloning and sequencing revealed that there was a single base substitution in ALE1, which encoded a ZDS involved in carotenoid biosynthesis. RNAi and complementation tests confirmed the identity of ALE1. Subcellular localization showed that the ALE1 protein is localized in the chloroplast. Expression analysis indicated that the genes involved in chlorophyll and carotenoid biosynthesis were downregulated. We conclude that ALE1 plays an important role in chloroplast and plant growth in rice.


Assuntos
Cloroplastos/enzimologia , Oryza/crescimento & desenvolvimento , Oxirredutases/genética , Proteínas de Plantas/genética , Clorofila/metabolismo , Cloroplastos/genética , Regulação da Expressão Gênica de Plantas , Oryza/enzimologia , Oryza/genética , Oxirredutases/metabolismo , Fotossíntese , Proteínas de Plantas/metabolismo , Interferência de RNA , Plântula/enzimologia , Plântula/genética , Plântula/crescimento & desenvolvimento
3.
Phytopathology ; 109(10): 1679-1688, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31479404

RESUMO

Alternative oxidase (AOX) is a ubiquinol terminal oxidase that is involved in fungal mitochondrial oxidative phosphorylation. In this study, we analyzed the roles of AOX in Botrytis cinerea by generating BcAOX deletion mutants. The mutants exhibited defects in mycelial growth, sporulation, spore germination, and virulence. Furthermore, the sensitivity of the mutants to quinone outside inhibitor fungicides and oxidative stress were increased. All phenotypic variations could be restored in the complemented strain. In summary, these results showed that BcAOX is involved in the regulation for vegetative development, adaptation to environmental stress, and virulence of B. cinerea.


Assuntos
Botrytis , Proteínas Mitocondriais , Oxirredutases , Oxigênio , Proteínas de Plantas , Botrytis/enzimologia , Botrytis/crescimento & desenvolvimento , Botrytis/patogenicidade , Proteínas Mitocondriais/metabolismo , Estresse Oxidativo/fisiologia , Oxirredutases/metabolismo , Proteínas de Plantas/metabolismo , Virulência
4.
Inorg Chem ; 58(17): 11649-11655, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31436093

RESUMO

A new mixed-valent dicopper complex [5] was generated from ligand exchange by dissolving a bis(CH3CN) precursor [3] in acetone. Introduction of a water molecule in place of an acetonitrile ligand was evidenced by base titration and the presence of a remaining coordinated CH3CN by IR, 19F NMR, and theoretical methods. The proposed structure (CH3CN-Cu-(SR)-Cu-OH2) was successfully DFT-optimized and the calculated parameters are in agreement with the experimental data. [5] has a unique temperature-dependence EPR behavior, with a localized valence from 10 to 120 K that undergoes delocalized at room temperature. The electrochemical signatures are in the line of the other aquo parent [2] and sensibly different from the rest of the series. Similar to the case of [2], [5] was finally capable of single turnover N2O reduction at room temperature. N2 was detected by GC-MS, and the redox character was confirmed by EPR and ESI-MS. Kinetic data indicate a reaction rate order close to 1 and a rate 10 times faster compared to [2]. [5] is thus the second example of that kind and highlights not only the main role of the Cu-OH2 motif, but also that the adjacent Cu-X partner (X = OTf- in [2] and CH3CN in [5]) is a new actor in the casting to establish structure/activity correlations.


Assuntos
Cobre/farmacologia , Inibidores Enzimáticos/farmacologia , Compostos Organometálicos/farmacologia , Oxirredutases/antagonistas & inibidores , Peptídeos/farmacologia , Cobre/química , Teoria da Densidade Funcional , Técnicas Eletroquímicas , Inibidores Enzimáticos/química , Estrutura Molecular , Compostos Organometálicos/química , Oxirredutases/metabolismo , Peptídeos/química
5.
Dokl Biochem Biophys ; 486(1): 234-237, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31367829

RESUMO

In this work, we investigated the NAD(P)-dependent dehydrogenase activity in different fields of the solid form of Ehrlich carcinoma. It was shown that there is a metabolic distinction between different fields of the solid tumor. In this way, there is a significant difference between the ascites and solid type of Ehrlich carcinoma. In the central area of the tested sample of tumor tissue, there is a high intensity of energetic metabolism and biosynthetic processes as opposed to the peripheral areas. Previously, we proposed the concept of nonspecific metabolic reaction of the cell in organism upon the influence of negative factors. In accordance with this concept, our results indicate the development of adaptation in the tumor cells in the central area of the tested sample.


Assuntos
Carcinoma de Ehrlich/metabolismo , Animais , NAD/metabolismo , Oxirredutases/metabolismo
6.
J Enzyme Inhib Med Chem ; 34(1): 1439-1450, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31409157

RESUMO

Leishmaniasis is a tropical disease found in more than 90 countries. The drugs available to treat this disease have nonspecific action and high toxicity. In order to develop novel therapeutic alternatives to fight this ailment, pteridine reductase 1 (PTR1) and dihydrofolate reductase-thymidylate synthase (DHF-TS) have been targeted, once Leishmania is auxotrophic for folates. Although PTR1 and DHFR-TS from other protozoan parasites have been studied, their homologs in Leishmania chagasi have been poorly characterized. Hence, this work describes the optimal conditions to express the recombinant LcPTR1 and LcDHFR-TS enzymes, as well as balanced assay conditions for screening. Last but not the least, we show that 2,4 diaminopyrimidine derivatives are low-micromolar competitive inhibitors of both enzymes (LcPTR1 Ki = 1.50-2.30 µM and LcDHFR Ki = 0.28-3.00 µM) with poor selectivity index. On the other hand, compound 5 (2,4-diaminoquinazoline derivative) is a selective LcPTR1 inhibitor (Ki = 0.47 µM, selectivity index = 20).


Assuntos
Inibidores Enzimáticos/farmacologia , Leishmania infantum/enzimologia , Complexos Multienzimáticos/antagonistas & inibidores , Oxirredutases/antagonistas & inibidores , Timidilato Sintase/antagonistas & inibidores , Catálise , Cromatografia de Afinidade , Clonagem Molecular , Avaliação Pré-Clínica de Medicamentos , Eletroforese em Gel de Poliacrilamida , Escherichia coli/genética , Concentração Inibidora 50 , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/isolamento & purificação , Complexos Multienzimáticos/metabolismo , Oxirredutases/genética , Oxirredutases/isolamento & purificação , Oxirredutases/metabolismo , Tetra-Hidrofolato Desidrogenase/genética , Tetra-Hidrofolato Desidrogenase/isolamento & purificação , Tetra-Hidrofolato Desidrogenase/metabolismo , Timidilato Sintase/genética , Timidilato Sintase/isolamento & purificação , Timidilato Sintase/metabolismo
7.
Bioresour Technol ; 291: 121854, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31357041

RESUMO

Two strains, Enterobacter sp. Z1 and Klebsiella sp. Z2, were exhibited great capacities for heterotrophic nitrification-aerobic denitrification (HNAD) and intracellular phosphate accumulation. Strikingly, the co-cultured strains enhanced the removal efficiency of total nitrogen and phosphate, with removal efficiencies of ammonia, nitrate, nitrite and soluble phosphate of 99.64%, 99.85%, 96.94% and 66.7% respectively. Furthermore, high removal efficiencies from wastewaters with high concentrations of ammonia (over 1000 mg/L) were achieved by inoculation with the co-strains, which left residual ammonia of less than 1 mg/L within 10 h. To elucidate the mechanism of HNAD in co-strains, quantitative PCR was carried out to examine the expression levels of hydroxylamine oxidase (Hao), nitrate reductase (NapA and NarG), nitrite reductase (NirS) and polyphosphate kinase (Ppk), and the results showed that the napA2, narG and ppk genes in the strains were significantly upregulated under the co-cultured conditions and provided an explanation for the nitrogen and phosphate removal.


Assuntos
Enterobacter/metabolismo , Klebsiella/metabolismo , Nitrogênio/metabolismo , Fosfatos/metabolismo , Amônia/metabolismo , Desnitrificação , Processos Heterotróficos , Nitrato Redutase/metabolismo , Nitratos/metabolismo , Nitrificação , Nitrito Redutases/metabolismo , Nitritos/metabolismo , Oxirredutases/metabolismo , Águas Residuárias
8.
Arch Insect Biochem Physiol ; 102(1): e21599, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31328816

RESUMO

A complementary DNA that encodes an omega-class glutathione S-transferase (GST) of the brown planthopper, Nilaparvata lugens (nlGSTO), was isolated by reverse transcriptase polymerase chain reaction. A recombinant protein (nlGSTO) was obtained via overexpression in the Escherichia coli cells and purified. nlGSTO catalyzes the biotransformation of glutathione with 1-chloro-2,4-dinitrobenzene, a general substrate for GST, as well as with dehydroascorbate to synthesize ascorbate. Mutation experiments revealed that putative substrate-binding sites, including Phe28, Cys29, Phe30, Arg176, and Lue225, were important for glutathione transferase and dehydroascorbate reductase activities. As ascorbate is a reducing agent, nlGSTO may participate in antioxidant resistance.


Assuntos
Glutationa Transferase/metabolismo , Hemípteros/enzimologia , Oxirredutases/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Insetos/metabolismo , Análise de Sequência de DNA
9.
Chem Commun (Camb) ; 55(62): 9148-9151, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31304493

RESUMO

Using superoxide reductase as a model system, a computational approach reveals how histidine tautomerism tunes the redox properties of metalloenzymes to enable their catalytic function. Inspired by these experimentally inaccessible insights, non-canonical histidine congeners are introduced as new versatile tools for the rational engineering of biological transition metal sites.


Assuntos
Oxirredutases/química , Oxirredutases/metabolismo , Elementos de Transição/metabolismo , Biocatálise , Modelos Moleculares , Estrutura Molecular , Oxirredução , Elementos de Transição/química
10.
J Agric Food Chem ; 67(30): 8312-8318, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31287303

RESUMO

The role of inositol 1,4,5-trisphosphate (IP3) in nitric oxide (NO)-reduced chilling injury (CI) in peach fruit was investigated. The fruit were immersed in sodium nitroprusside (SNP) (NO donor) and neomycin (IP3 inhibitor). Results showed that chilling tolerance was enhanced upon exogenous SNP in postharvest peach fruit. Further, GABA accumulation was stimulated by SNP. The increase in protein expression and activity for enzymes in GABA biosynthesis, including glutamate decarboxylase (GAD), polyamine oxidase (PAO), and amino aldehyde dehydrogenase (AMADH), upon SNP treatment was also observed. Also, the up-regulation of Δ1-pyrroline-5-carboxylate synthetase (P5CS) and ornithine d-aminotransferase (OAT) and the down-regulation of proline dehydrogenase (PDH) were induced by SNP treatment, thereby accelating proline production. Additionally, SNP treatment elevated protein expression and activity of alternative oxidase (AOX). The above effects induced upon SNP were partly weakened by neomycin. Therefore, IP3 mediated NO-activated GABA and proline accumulation as well as AOX, thus inducing chilling tolerance in postharvest peach fruit.


Assuntos
Frutas/química , Inositol 1,4,5-Trifosfato/metabolismo , Óxido Nítrico/metabolismo , Prunus persica/metabolismo , Aldeído Desidrogenase/metabolismo , Temperatura Baixa , Armazenamento de Alimentos , Frutas/metabolismo , Glutamato Descarboxilase/metabolismo , Proteínas Mitocondriais/metabolismo , Oxirredutases/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/metabolismo , Proteínas de Plantas/metabolismo , Prolina/metabolismo , Prunus persica/química , Prunus persica/enzimologia , Ácido gama-Aminobutírico/metabolismo
11.
Inorg Chem ; 58(15): 9557-9561, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31313577

RESUMO

An iron(III) methoxide complex reacts with para-substituted triarylmethyl radicals to give iron(II) and methoxyether products. Second-order rate constants for the radical derivatives were obtained. Hammett and Marcus plots suggest the radical transfer reactions proceed via a concerted process. Calculations support the concerted nature of these reactions involving a single transition state with no initial charge transfer. These findings have implications for the radical "rebound" step invoked in nonheme iron oxygenases, halogenases, and related synthetic catalysts.


Assuntos
Compostos Férricos/metabolismo , Compostos Ferrosos/metabolismo , Oxirredutases/metabolismo , Oxigênio/metabolismo , Oxigenases/metabolismo , Biocatálise , Compostos Férricos/química , Compostos Ferrosos/química , Estrutura Molecular , Oxirredutases/química , Oxigênio/química , Oxigenases/química
12.
Environ Sci Pollut Res Int ; 26(22): 22338-22350, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31154641

RESUMO

A pot experiment was performed to assess the useful effects of seed soaking or seedling foliar spray using 0.25 mM spermine (Spm), 0.50 mM spermidine (Spd), or 1 mM putrescine (Put) on heavy metal tolerance in wheat plants irrigated with water contaminated by cadmium (2 mM Cd2+ in CdCl2) or lead (2 mM Pb2+ in PbCl2). Cd2+ or Pb2+ presence in the growth medium resulted in significant reductions in growth and yield characteristics and activities of leaf peroxidase (POD), glutathione reductase (GR), ascorbic acid oxidase (AAO), and polyphenol oxidase (PPO) of wheat plants. In contrast, significant increases were observed for Cd2+ content in roots, leaves and grains, superoxide dismutase (SOD) and catalase (CAT) activities, radical scavenging activity (DPPH), reducing power capacity, and fragmentation in DNA in comparison to controls (without Cd2+ or Pb2+ addition). However, treating the Cd2+- or Pb2+-stressed wheat plants with Spm, Spd, or Put, either by seed soaking or foliar spray, significantly improved growth and yield characteristics and activities of POD, GR, AAO, PPO, SOD, and CAT, DPPH, and reducing power capacity in wheat plants. In contrast, Cd2+ levels in roots, leaves, and yielded grains, and fragmentation in DNA were significantly reduced compared with the stressed (with Cd2+ or Pb2+) controls. Generally, seed soaking treatments were more effective than foliar spray treatments. More specifically, seed priming in Put was the best treatment under heavy metal stress. Results of this study recommend using polyamines, especially Put, as seed soaking to relieve the adverse effects of heavy metals in wheat plants.


Assuntos
Antioxidantes/farmacologia , Inativação Metabólica/efeitos dos fármacos , Oxirredutases/metabolismo , Plântula/efeitos dos fármacos , Espermidina/farmacologia , Espermina/farmacologia , Superóxido Dismutase/metabolismo , Antioxidantes/química , Ácido Ascórbico/farmacologia , Cádmio/química , DNA , Genômica , Glutationa Redutase/metabolismo , Oxirredução , Peroxidases/metabolismo , Folhas de Planta/metabolismo , Poliaminas , Sementes/metabolismo , Espermidina/química , Triticum/crescimento & desenvolvimento
13.
Plant Physiol Biochem ; 141: 225-230, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31185367

RESUMO

The present study evaluated the role of nitric oxide (NO) in mediating adventitious root (AR) growth, lignification and related enzymatic changes in the hypocotyls of Vigna radiata. To meet the objectives, the changes in AR growth, lignin content, and the activities of enzymes-peroxidases, polyphenol oxidases, and phenylalanine ammonia lyases- with NO donor and its scavenger were monitored. Hypocotyls were cultivated in aqueous solution supplemented with different concentrations of SNP (sodium nitroprusside, NO donor compound) and its scavenging compound (2,4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide; cPTIO). Specifically, at low concentrations, SNP induced AR growth, increased the total lignin content and altered the activities of related oxidoreductases- peroxidases, polyphenol oxidases and phenylalanine ammonia lyases- which are involved in lignin biosynthesis pathway. At higher concentrations, a decline in AR growth and lignification was noticed. We analysed the function of NO in AR formation by depleting the endogenous NO using scavenging compound cPTIO. Hypocotyls grown in a medium supplemented with scavenger cPTIO exhibited significant decline in AR growth and the activities of lignin synthesizing enzymes. Application of NO scavenger showed that stimulatory properties on root lignification may be owing to NO itself. In addition, changes in AR growth were significantly correlated with these modified biochemical activities. Our analysis revealed that NO supplementation induces prominent alterations in lignin level during AR formation and this might be due to an alteration in the activity of lignin biosynthetic enzymes, which further affected the polymerization of monolignols and AR growth.


Assuntos
Hipocótilo/enzimologia , Lignina/química , Óxido Nítrico/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Vigna/enzimologia , Catecol Oxidase/metabolismo , Oxirredutases/metabolismo , Peroxidase/metabolismo , Fenilalanina Amônia-Liase/metabolismo , Raízes de Plantas/enzimologia
14.
Klin Lab Diagn ; 64(5): 260-264, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31185147

RESUMO

The activity of amino acid metabolism enzymes and the content of free amino acids in the placenta during physiological pregnancy and placental insufficiency (PI) were studied using spectrophotometric methods and ion-exchange chromatography. It was found that in PI placental activity of the studied enzymes: alanine-, cysteine-e, tyrosine-, glutamino- transferase, glutathione synthetase, glutamate dehydrogenase decreases at different periods of gestation. The opposite variations occur for aspartataminotranferase and glutaminase. Similar changes are detected for amino acids synthesized or used in the course of appropriate reactions: aspartic acid, glutamic acid, glutamine, alanine, cysteine, tyrosine, arginine. The correlation between enzyme activity and amino acid content was revealed. Different periods of pregnancy are characterized by varying degrees of change, especially expressed in the second trimester, characterized by the most intense growth and development of the fetus, and its increased needs for trophic material. The revealed changes obviously play a pathogenetic role in the formation and further development of PI.


Assuntos
Aminoácidos/metabolismo , Placenta/enzimologia , Complicações na Gravidez/enzimologia , Aspartato Aminotransferases/metabolismo , Feminino , Glutaminase/metabolismo , Humanos , Oxirredutases/metabolismo , Insuficiência Placentária/enzimologia , Gravidez
15.
Plant Physiol Biochem ; 141: 415-422, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31229926

RESUMO

This study aimed to investigate the possible alleviating effect of chitosan on salt-induced growth retardation and oxidative stress and to elucidate whether this effect is linked to activation of mitochondrial respiration on the basis of alternative respiration in maize seedlings. Salt stress significantly reduced root length and plant height in comparison to the control, whereas foliar application of chitosan ameliorated the adverse effect of salinity to a certain degree. Moreover, chitosan resulted in plant growth promotion as compared to unstressed seedlings. The separate applications of chitosan and salt had a stimulatory effect on the activities of antioxidant enzymes; however, combined application of chitosan and salt were more effective than that of chitosan or salt alone. Similarly, mitochondrial total respiration rate (Vt) and alternative respiration capacity (Valt) were increased by separate applications of chitosan and salt; however, the combination of chitosan and salt gave the highest values for these parameters. The highest values of Valt/Vt was recorded at seedlings treated with salt plus chitosan. Similarly, cytochrome respiration capacity was also increased by chitosan in both stress-free and stressed conditions. In addition, AOX1, encoding alternative oxidase, was significantly upregulated by chitosan and/or salt. The maximum transcript level was recorded at seedlings treated with salt plus chitosan. Chitosan also significantly decreased superoxide anion and hydrogen peroxide contents and lipid peroxidation level under normal and the stressed conditions. These results suggest that the mitigating effect of chitosan on salt stress is linked to activation of alternative respiration at biochemical and molecular level.


Assuntos
Quitosana/química , Regulação da Expressão Gênica de Plantas , Proteínas Mitocondriais/metabolismo , Oxirredutases/metabolismo , Proteínas de Plantas/metabolismo , Tolerância ao Sal , Plântula/genética , Zea mays/genética , Antioxidantes/metabolismo , Citocromos/metabolismo , Perfilação da Expressão Gênica , Peroxidação de Lipídeos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Estresse Oxidativo , Oxirredutases/genética , Proteínas de Plantas/genética , RNA/metabolismo , Estresse Fisiológico , Zea mays/enzimologia
16.
J Agric Food Chem ; 67(26): 7399-7409, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31244203

RESUMO

Flavonol synthase (FLS) belongs to the 2-oxoglutarate-dependent dioxygenase (2-ODD) superfamily. We isolated OsFLS from the rice ( Oryza sativa) cultivar "Ilmi" OsFLS includes highly conserved 2-ODD-specific motifs and FLS-specific regions. Recombinant OsFLS exhibited both FLS and flavanone 3ß-hydroxylase (F3H) activities, converting dihydroflavonols into flavonols and flavanones into dihydroflavonols, respectively, and more efficiently used dihydrokaempferol than dihydroquercetin as a substrate. OsFLS was expressed in both nonpigmented and pigmented rice seeds and was developmentally regulated during seed maturation. Transgenic tobacco ( Nicotiana tabacum) plants expressing OsFLS produced pale pink or white flowers with significantly increased levels of kaempferol-3- O-rutinoside and dramatically reduced levels of anthocyanin in their petals. Additionally, pod size and weight were reduced compared to the wild type. Several early and late biosynthetic genes of flavonoid were downregulated in the transgenic flowers. We demonstrated that OsFLS is a bifunctional 2-ODD enzyme and functions in flavonol production in planta.


Assuntos
Dioxigenases/genética , Dioxigenases/metabolismo , Oryza/enzimologia , Oxirredutases/genética , Oxirredutases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Antocianinas/biossíntese , Cor , Flavonóis/biossíntese , Flores/genética , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Cetoglutáricos/metabolismo , Oryza/genética , Tabaco/genética , Tabaco/metabolismo
17.
Plant Sci ; 285: 1-13, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31203874

RESUMO

Bioactive gibberellins (GAs) play multiple roles in plant development and stress responses. GA2-oxidases (GA2oxs) are a class of 2-oxoglutarate-dependent dioxygenases that regulate the deactivation of bioactive GAs. In this study, we investigated the phylogeny and domain structures of the seven GA2ox genes present in the Arabidopsis thaliana genome. Comprehensive expression analysis using translational reporter lines showed that the seven GA2ox genes are differentially expressed during Arabidopsis growth and development: GA2ox1 is specifically expressed in the hypocotyl and lateral root primordium; GA2ox2 is highly expressed in aboveground tissues; GA2ox3 is expressed in the chalazal endosperm of the early embryo sac and inflorescences; GA2ox4 is expressed in the shoot apical meristem and during lateral root initiation; GA2ox6 is expressed in the maturation zone, but not in the meristem or elongating zone of the root; GA2ox7 is constitutively expressed during almost all developmental stages; and GA2ox8 is exclusively expressed in stomatal cells. Overexpression of each of these GA2ox genes inhibited high temperature-induced hypocotyl elongation in both wild-type and elongated hypocotyl 5 plants, which have an elongated hypocotyl phenotype, suggesting that these genes negatively regulate hypocotyl elongation by reducing bioactive GA levels. This study provides a valuable resource for further elucidating the roles of GA2ox genes during different stages of development.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Genes de Plantas/fisiologia , Giberelinas/metabolismo , Oxirredutases/genética , Arabidopsis/enzimologia , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/fisiologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Giberelinas/fisiologia , Hipocótilo/crescimento & desenvolvimento , Hipocótilo/metabolismo , Oxirredutases/metabolismo , Oxirredutases/fisiologia , Filogenia , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Transcriptoma
18.
Ecotoxicol Environ Saf ; 181: 312-320, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31202931

RESUMO

The effect of manure compost alone and combined with Streptomyces pactum (Act12) applied in the smelter-contaminated soil was investigated. The soil fertility, enzymatic activities, potentially toxic metals (PTMs) solubility, and phytoremediation efficiency of potherb mustard (Brassica juncea, Coss.) were assessed. Results showed that the application of compost reduced the soil pH, while significantly increased the soil electrical conductivity (EC) (7.0 folds), available phosphorus (AP) (10.8 folds), available potassium (AK) (2.81 folds), dissolved organic carbon (DOC) (5.22 folds), organic matter (OM) (4.93 folds), together with soil enzymatic activities viz. urease (UR) (4.39 folds), dehydrogenase (DEH) (45.0 folds) and alkaline phosphatase (ALP) (123.9 folds) in comparison with control. The inoculation of Act12 increased AP, AK, DOC, OM and UR values, but reduced EC, DEH and ALP values compared to corresponding lone compost amendment. Additionally, Act12 solubilized PTMs (Cd and Zn) in the soil, and accordingly enhanced the PTMs uptake in the plant. The phytoextraction indices viz. biological concentration factor (BCF), translocation factor (TF) and metal extraction amount (MEA) indicated that compost and Act12 had a synergistic role in enhancing the phytoremediation efficiency, among which MEA values of Cd and Zn maximally increased by 9.64 and 11.4 folds, respectively, compared to control. Redundancy analysis (RDA) indicated that phytoextraction indices correlated well with soil parameters. Our results suggested that manure compost associated with Act12 is a potential strengthening strategy in phytoremediation of PTMs contaminated soil.


Assuntos
Compostagem , Metais Pesados/metabolismo , Poluentes do Solo/metabolismo , Streptomyces/fisiologia , Fosfatase Alcalina/metabolismo , Biodegradação Ambiental , Cádmio/metabolismo , Esterco , Metais Pesados/toxicidade , Mostardeira/metabolismo , Oxirredutases/metabolismo , Solo/química , Poluentes do Solo/toxicidade , Urease/metabolismo , Zinco/metabolismo
19.
Mar Drugs ; 17(6)2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151157

RESUMO

Thioacetamide (TAA) is known to induce lipid accumulation in the liver. In the present study, we investigated the effects of magma seawater (MS) rich in minerals on hepatic lipid metabolism by evaluating lipogenic enzymes regulated by sterol regulatory element-binding proteins (SREBPs). Rats (n = 10 per group) were intraperitoneally injected with TAA (200 mg/kg bw) thrice a week for seven weeks in combination with a respective experimental diet. Rats in the TAA-treated group received either a chow diet (Control group) or a chow diet containing MS (TMS group, 2.05%) or silymarin (TSM group, 0.05%). Rats in the normal group were injected with PBS as a vehicle and received a chow diet. Rats in the TMS group showed significantly lower hepatic lipid concentrations than rats in the control group (p < 0.05). Hepatic protein expression levels of fatty acid synthase, SREBP-1, 3-hydroxy-3-methylglutaryl-coenzyme A reductase, and SREBP-2 were significantly downregulated in the TMS group, whereas carnitine palmitoyltransferase 1 levels were upregulated (p < 0.05). Hepatic thiobarbituric acid reactive substances levels were lower in the TMS group, whereas protein levels of glutathione peroxidase and catalase were elevated (p < 0.05). The effects of MS were comparable to those of silymarin. Our results evidently showed that MS inhibits hepatic lipid accumulation by suppressing lipid synthesis, accompanied by lipid oxidation and elevation of antioxidative status.


Assuntos
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado , Minerais/farmacologia , Água do Mar/química , Proteínas de Ligação a Elemento Regulador de Esterol/metabolismo , Tioacetamida/farmacologia , Animais , Dieta , Fígado/química , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Minerais/administração & dosagem , Oxirredutases/genética , Oxirredutases/metabolismo , Ratos , Ratos Sprague-Dawley , Ganho de Peso/efeitos dos fármacos
20.
Aquat Toxicol ; 212: 186-193, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31129414

RESUMO

Ocean acidification (OA) is caused by alteration of global ocean carbon chemistry due to the increased pCO2 in the atmosphere and caused deleterious impacts on the marine ecosystem. Although various detrimental effects of OA were reported in marine organisms, the potential impact of OA on aquatic invertebrates still remains largely unknown. Here, we examined changes in life parameters and antioxidant system in response to low pH (7.5 and 7) in the marine copepod Tigriopus japonicus. Exposures to lower pHs (pH 7.5 and 7.0) of copepods resulted in lengthening of the developmental time with decreased fecundity and body length. Also, they showed increased reactive oxygen species contents with enhanced glutathione S-transferase and glutathione reductase activities but decreased glutathione peroxidase and superoxide dismutase activities in pH-dependent manner, indicating that OA exposure caused disturbance of the redox system in T. japonicus. Among several oxidative stress-related genes, GSTs2b was significantly up-regulated in response to OA. These findings will be helpful for a better understanding on the potential impact of OA on life parameters and antioxidant system in the marine copepod T. japonicus.


Assuntos
Copépodes/fisiologia , Estresse Oxidativo/fisiologia , Oxirredutases/metabolismo , Água do Mar/química , Animais , Tamanho Corporal/fisiologia , Carbono/química , Fertilidade/fisiologia , Concentração de Íons de Hidrogênio , Oceanos e Mares , Oxirredução , Espécies Reativas de Oxigênio
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