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1.
Int J Mol Sci ; 22(6)2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33809742

RESUMO

The voltage-dependent anion channel (VDAC) is the major pathway for metabolites and ions transport through the mitochondrial outer membrane. It can regulate the flow of solutes by switching to a low conductance state correlated with a selectivity reversal, or by a selectivity inversion of its open state. The later one was observed in non-plant VDACs and is poorly characterized. We aim at investigating the selectivity inversion of the open state using plant VDAC purified from Phaseolus coccineus (PcVDAC) to evaluate its physiological role. Our main findings are: (1) The VDAC selectivity inversion of the open state occurs in PcVDAC, (2) Ion concentration and stigmasterol affect the occurrence of the open state selectivity inversion and stigmasterol appears to interact directly with PcVDAC. Interestingly, electrophysiological data concerning the selectivity inversion of the PcVDAC open state suggests that the phenomenon probably does not have a significant physiological effect in vivo.


Assuntos
Phaseolus/metabolismo , Sementes/metabolismo , Estigmasterol/metabolismo , Canais de Ânion Dependentes de Voltagem/metabolismo , Medição da Troca de Deutério , Ativação do Canal Iônico/efeitos dos fármacos , Íons , Cinética , Lipossomos , Concentração Osmolar , Phaseolus/efeitos dos fármacos , Sementes/efeitos dos fármacos , Estigmasterol/farmacologia
2.
Nat Plants ; 7(1): 50-59, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33452489

RESUMO

Long-distance RNA movement is important for plant growth and environmental responses; however, the extent to which RNAs move between distant tissues, their relative magnitude and functional importance remain to be elucidated on a genomic scale. Using a soybean (Glycine max)-common bean (Phaseolus vulgaris) grafting system, we identified 100 shoot-root mobile microRNAs and 32 shoot-root mobile phased secondary small interfering RNAs (phasiRNAs), which were predominantly produced in shoots and transported to roots, and, in most cases, accumulated to a level similar to that observed in shoots. Many of these microRNAs or phasiRNAs enabled cleavage of their messenger RNA targets or phasiRNA precursors in roots. In contrast, most mobile-capable mRNAs were transcribed in both shoots and roots, with only small proportions transported to recipient tissues. These findings suggest that the regulatory mechanisms for small RNA movement are different from those for mRNA movement, and that the former is more strictly regulated and, probably, more functionally important than the latter.


Assuntos
MicroRNAs/metabolismo , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , RNA de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Phaseolus/metabolismo , RNA Mensageiro/metabolismo , Soja/metabolismo
3.
Mol Genet Genomics ; 296(2): 379-390, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33449160

RESUMO

Common bean (Phaseolus vulgaris L.) is a short-day plant and its flowering time, and consequently, pod yield and quality is influenced by photoperiod. In this study, the photoperiodic-sensitive variety 'Hong jin gou', which flowers 31 days (d) earlier in short-day than in long-day, was used as the experimental material. Samples were collected to determine the growth and photosynthetic parameters in each daylength treatment, and transcriptome and metabolome data were conducted. We identified eight genes related to flowering by further screening for differentially expressed genes. These genes function to regulate the biological clock. The combination of differentially expressed genes and metabolites, together with the known regulation network of flowering time and the day-night expression pattern of related genes allow us to speculate on the regulation of flowering time in the common bean and conclude that TIMING OF CAB EXPRESSION1 (TOC1) plays a pivotal role in the network and its upregulation or downregulation causes corresponding changes in the expression of downstream genes. The regulatory network is also influenced by gibberellic acid (GA) and jasmonic acid (JA). These regulatory pathways jointly comprise the flowering regulatory network in common bean.


Assuntos
Perfilação da Expressão Gênica/métodos , Metabolômica/métodos , Phaseolus/fisiologia , Fatores de Transcrição/genética , Relógios Biológicos , Flores/fisiologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Giberelinas/farmacologia , Ácidos Linoleicos/farmacologia , Phaseolus/genética , Phaseolus/metabolismo , Fotoperíodo , Proteínas de Plantas/genética , Análise de Sequência de RNA
4.
Carbohydr Polym ; 253: 117351, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33278961

RESUMO

The role of the plant matrix is recognized as the main factor restricting starch digestibility in beans. Several authors have provided insights about the mechanisms behind the reduced starch digestibility in plant matrices. In this study, by means of a mathematical model, we provide a mechanistic explanation of the role played by the cell wall. It was confirmed that starch entrapped within intact cells could only be hydrolysed after α-amylase diffusion through the cell wall. This process is limited by the pores naturally present in the cell wall and the adsorption of α-amylase to the cell wall surface. These factors restrict the concentration of α-amylase available within the cells. The model assumptions are valid under controlled laboratory conditions and were validated with in-vitro digestion data giving very accurate results. The proposed approach provides new information to understand the digestibility of starch, and possibly other macronutrients, in complex food matrices.


Assuntos
Parede Celular/metabolismo , Cotilédone/citologia , Cotilédone/metabolismo , Digestão/fisiologia , Modelos Teóricos , Phaseolus/metabolismo , Amido/metabolismo , Adsorção , Animais , Difusão , Mucosa Gástrica/enzimologia , Hidrólise , Cinética , Pâncreas/enzimologia , Porosidade , Suínos , alfa-Amilases/metabolismo
5.
J Sci Food Agric ; 101(2): 449-458, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32648589

RESUMO

BACKGROUND: Various foods are known to have beneficial effects on health when consumed whole; however, there is a trend towards preparing foods from processed ingredients, and it remains unclear whether the benefits of the whole food are retained. The purpose of this study was therefore to examine whether different processing techniques affect the lowering of cholesterol and the vascular effects of black beans (Phaseolus vulgaris L.). RESULTS: Beans were prepared by overnight soaking and boiling - the standard method - and by micronization, extrusion, or dehulling and boiling, and they were then fine milled. Beans prepared by the standard method were also coarse milled. These five materials were incorporated into semi-purified diets (30% wt/wt) and fed to spontaneously hypertensive rats for 4 weeks. Body weight, blood pressure, and aorta morphology were unaltered by the diets. Fasting total cholesterol was significantly reduced in rats fed micronized beans compared with extruded beans (both fine-milled) or the bean-free diet, while boiling combined with coarse milling lowered low-density lipoprotein (LDL) cholesterol. The lack of cholesterol lowering in rats fed extruded bean compared to micronized was not explained by the amount or composition of dietary fiber or resistant starch. Differences in the polyphenolic profile as determined by high-performance liquid chromatography (HPLC) were also unable to explain the variations in cholesterol-lowering capacity. CONCLUSION: The present study demonstrates that processing of black beans alters the health effects observed with the whole pulse, and suggests that products prepared with processed ingredients will need to be tested empirically to establish whether the biological effects are maintained in vivo. © 2020 Society of Chemical Industry.


Assuntos
Colesterol/metabolismo , Culinária/métodos , Hipertensão/metabolismo , Phaseolus/metabolismo , Sementes/química , Animais , Fibras na Dieta/análise , Humanos , Hipertensão/dietoterapia , Lipoproteínas LDL/metabolismo , Masculino , Phaseolus/química , Ratos , Ratos Endogâmicos SHR , Sementes/metabolismo
6.
Food Chem ; 338: 128074, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32950011

RESUMO

A separation and analysis method of fosthiazate stereoisomers was established utilizing supercritical fluid chromatography-tandem mass spectrometry (SFC-MS/MS) with a CHIRALPAK AD-3 column. The determination of the four fosthiazate stereoisomers could be completed within 6 min. The environmental behaviors of fosthiazate stereoisomers were studied in legume vegetables. After applying fosthiazate granules to soil, the concentrations of fosthiazate stereoisomers in the legume vegetables increased with time, reached maximum values in 7-10 days, and then decreased gradually in all legumes except for in Glycine max. No obvious dissipation behaviors were observed in Glycine max. Interestingly, the stereoselective behaviors were species-specific. A-(-), B-(-) and B-(±)-fosthiazate were preferentially enriched in Phaseolus vulgaris Linn and Vigna unguiculata, while A-(+) and A-(±)-fosthiazate preferentially accumulated in Vicia faba Linn, Pisum sativum Linn and G. max. The opposite stereoselectivity of B-(±)-fosthiazate was observed in different growth stage of G. max. No stereoselective dissipation occurred in soil.


Assuntos
Fabaceae/química , Compostos Organofosforados/química , Espectrometria de Massas em Tandem/métodos , Tiazolidinas/química , Cromatografia com Fluido Supercrítico , Fabaceae/metabolismo , Ervilhas/química , Ervilhas/metabolismo , Phaseolus/química , Phaseolus/metabolismo , Soja/química , Soja/metabolismo , Estereoisomerismo , Vicia faba/química , Vicia faba/metabolismo
7.
Food Chem ; 339: 127917, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32950898

RESUMO

Andean beans (Phaseolus vulgaris) chemical compositions and cooking characteristics contribute to a healthy diet. The objective of this study was to evaluate the influence of chemical composition on the cooking quality of 14 Andean beans genotypes with different seed coat colors. More specifically, water retention (WR), cooking time (CT), and solids released in the broth, were analysed. WR values ranged from 128.4% to 160.7% and CT ranged from 13.7 (BRS Embaixador) to 21.7 min (KID44). Andean beans showed variability in chemical composition, mainly starch content (39.43 g 100 g-1, BRS Realce to 51.92 g 100 g-1, LP15-04) and polymer composition. The profile of starch and interactions among minerals and chemical compounds influenced the cooking profiles than do the individual compounds. Andean beans traits of cooking, mainly CT, were influenced by their chemical composition; however they can be incorporated into diets without drastic changes in preparation methods.


Assuntos
Culinária/métodos , Phaseolus/química , Amido/análise , Amilopectina/análise , Amilose/análise , Genótipo , Minerais/análise , Análise Multivariada , Phaseolus/genética , Phaseolus/metabolismo , Sementes/química , Sementes/genética , Sementes/metabolismo
8.
PLoS One ; 15(8): e0235355, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32817671

RESUMO

The Arbuscular mycorrhizal fungi (AMF) (Funneliformis mosseae), are the most widely distributed symbiont assisting plants to overcome counteractive environmental conditions. In order to improve the sustainability and the activity of AMF, the use of nanotechnology was important. The main objective of this study was to investigate the effect of titanium dioxide nanoparticles (TiO2NPs) on the activity of AMF in common bean roots as well as its activity under salinity stress using morphological and molecular methods. The activity of AMF colonization has increased in the presence of TiO2NPs especially for arbuscule activity (A%), which increased three times with the presence of TiO2NPs. The improvement rate of Funneliformis mosseae on plant growth increased from 180% to 224% of control at the lowest level of salinity and increased from 48% to 130% at higher salinity level, respectively. The AMF dependencies for plant dry biomass increased in the presence of TiO2NPs from 277% in the absence of salinity to 465 and 883% % at low and high salinity levels, respectively. The presence of AMF co-inoculated with TiO2NPs resulted in increasing the salinity tolerance of plants at all levels and reached 110% at salinity level of 100 mM NaCl. Quantitative colonization methods showed that the molecular intensity ratio and the relative density of paired inocula AMF Nest (NS) or chitin synthases gene (Chs) with TiO2NPs were higher significantly P.>0.05 than single inoculants of AMF gene in roots under the presence or the absence of salinity by about two folds and about 40%. Hence, the positive effect of TiO2NPs was confined to its effect on AMF not on bean plants itself.


Assuntos
Ascomicetos/patogenicidade , Nanopartículas Metálicas/química , Phaseolus/microbiologia , Tolerância ao Sal , Ascomicetos/efeitos dos fármacos , Ascomicetos/metabolismo , Quitina Sintase/genética , Quitina Sintase/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Nanopartículas Metálicas/microbiologia , Phaseolus/metabolismo , Simbiose , Titânio/química , Titânio/farmacologia
9.
Mol Genet Genomics ; 295(6): 1325-1337, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32607601

RESUMO

The main edible organ of snap bean (Phaseolus vulgaris L.) is the pod, whose color is a main characteristic affecting its commercial use. Golden pods are popular with consumers; however, color instability affects their commercial exploitation and causes economic losses to the planters. In this study, we focused on the different pod color of two varieties of snap bean. The golden yellow color of snap bean pods is controlled by a single recessive nuclear gene located at 1-4.24 Mb of chromosome 2. To explore the physiological and molecular mechanism of the golden pod color, the golden bean line 'A18-1' and the green bean line 'Renaya' were selected as experimental materials. We analyzed the pigment contents, detected the intermediate products of chlorophyll biosynthesis, and identified differentially expressed genes using RNA-seq. The formation of golden bean pods reflects a chlorophyll deficiency, which was speculated to be caused by impairment of the Mg-protoporphyrin IX to chlorophyllide step. In 'A18-1' and 'Renaya' pods on 10, 14, and 18 days, five genes related to this step were differentially expressed, all of which were protochlorophyllide oxidoreductase (POR) genes. Among them, the expression changes of the Phvul. 004G112700, Phvul.007G157500, and Phvul. 004G112400 genes were consistent with the color change and physiological data during pod development in 'A18-1' and 'Renaya'. We speculated that the altered expression of these three POR genes might be related to changes in the chlorophyllide content. The results might provide insight into the understanding of chlorophyll biosynthesis and crop breeding for snap bean.


Assuntos
Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas , Phaseolus/metabolismo , Proteínas de Plantas/metabolismo , Sementes/metabolismo , Vicia faba/metabolismo , Cor , Phaseolus/genética , Phaseolus/crescimento & desenvolvimento , Proteínas de Plantas/genética , Sementes/genética , Sementes/crescimento & desenvolvimento , Transcriptoma , Vicia faba/genética , Vicia faba/crescimento & desenvolvimento
10.
PLoS One ; 15(6): e0234512, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32511280

RESUMO

Nutritional deficiencies limit the growth of snap bean plants, therefore knowing the biological mechanisms involved in it is fundamental. This study is aimed to evaluate the damage caused by a deficiency of macronutrients in physiological variables that cause decreased growth and the appearance of visual symptoms in snap bean. Thus, we design a hydroponic system of snap bean cultivation in order to test the effect of macronutrient deficiencies in a controlled environment. The treatments consisted in evaluate the effects of lack of one macronutrient in time. To perform this, we used Hoagland and Arnon solution in its complete formulation (control) or without N, P; K; Mg, Ca or S in each treatment. Physiological, nutritional, and growth analyses were performed when visual deficiency symptoms of each omitted nutrient appeared. Thus, the omissions of N and P in the nutrient solution led to lower accumulations of all macronutrients in the shoot. And the K, Ca, Mg, and S omissions decreased the amounts of K, Ca, Mg, P, and S in the shoot of the snap bean plants when compared with the plants grown in the complete nutrient solution. With the lowest accumulation of macronutrients, the content of photosynthetic pigments and the photosynthetic rate were reduced, with harmful effects on plant growth. Thus, from the losses in dry matter production of the shoot, the order of limiting of macronutrients in bean plants was N < P < Ca < S < Mg < K, with a decrease of up to 86.2%, 80.1%, 51.2%, 46.5%, 25.6%, and 19.3%, respectively. The nitrogen deficiency is more evident, proven by symptoms such as chlorosis in the lower and upper third leaves and necrosis of the lower third leaves.


Assuntos
Nitrogênio/metabolismo , Nutrientes/metabolismo , Phaseolus/crescimento & desenvolvimento , Fotossíntese/genética , Ambiente Controlado , Hidroponia , Nutrientes/fisiologia , Phaseolus/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Potássio/metabolismo
11.
Food Chem ; 329: 127183, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32521427

RESUMO

Combined effects of pH and thermal treatments on black kidney bean lectin (BKBL) were investigated by response surface methodology (RSM). Low-pH (1.0, 2.0, 3.0) incubation decreased hemagglutination activity (HA) and IgE-binding capacity, but the activities would be restored when the lectin was treated by pH shifting to 7.2. Conformational structure analyses indicated that low-pH induced protein unfolding and pH-shifting treatment resulted in a limited structural rearrangement. Mild heating, such as 60 °C for 3 min, slightly increased the HA and IgE-binding activities of pH shifted BKBL, but no obvious effects in the pH 1.0 incubated BKBL. High-temperature and long-time treatment might induce the protein aggregation, further decreased HA and IgE-binding capacities. RSM results showed both IgE-binding capacity and HA were the lowest under the combination of pH 1.0 incubation with 80 °C heating for 15 min or pH shifting from 1.0 to 7.2 with 100 °C heating for 10 min.


Assuntos
Imunoglobulina E/metabolismo , Lectinas/química , Phaseolus/metabolismo , Dicroísmo Circular , Temperatura Alta , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Lectinas/metabolismo , Agregados Proteicos , Conformação Proteica em alfa-Hélice , Estrutura Terciária de Proteína , Espectrometria de Fluorescência
12.
Ecotoxicol Environ Saf ; 200: 110732, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32460049

RESUMO

This paper reports the role of exogenous glycine betaine (25 and 50 mM GB at a rate of 50 mL per plant) in enhancing NaCl-stress tolerance in common bean (Phaseolus vulgaris L.). Irrigating plants by simulated saline water, containing 0, 50 and 100 mM sodium chloride (NaCl), significantly reduced the growth dynamics, photosynthetic pigments (i.e., Chl a, Chl b, and carotenoids), membrane stability index (MSI), relative water content (RWC), and pod yield. While, malondialdehyde (MDA), endogenous proline, and glutathione contents, electrolyte leakage (EL), antioxidant defense system, and Na+ accumulation markedly increased upon exposure to NaCl-stress. However, the application of exogenous GB significantly improved salt tolerance of common bean as it increased the antioxidant defense including both enzymatic (i.e., peroxidase, superoxide dismutase, and catalase) and nonenzymatic (i.e., proline and glutathione) agents. Consequently, MSI, RWC, EL, and photosynthetic pigments have been improved recording significantly higher values than the control. Moreover, the pod yield increased by 29.8 and 59.4% when plants grown under 50 and 100 mM NaCl, respectively, were sprayed with 25 mM GB. Our results show that GB-induced slat tolerance in common bean plants mainly depends on the osmoregulation effect of GB and to a lesser extent on its antioxidant capacity. Foliar application of GB significantly reduced the accumulation of Na+ and at the same time induced K+ uptake maintaining a higher K+/Na+ ratio. Despite some changes in the activities of antioxidant enzymes induced by the application of GB, no consistent contribution in the salt tolerance could be cited in this study. Therefore, we suggest that salt tolerance is largely unrelated to the antioxidant defense ability of GB in common bean. While the potential role of GB in ameliorating salt tolerance is mainly due to the adjustment of ions uptake through limiting Na+ uptake and alternatively increasing K+ accumulation in plant tissues.


Assuntos
Betaína/farmacologia , Phaseolus/efeitos dos fármacos , Potássio/metabolismo , Tolerância ao Sal , Sódio/metabolismo , Antioxidantes/metabolismo , Transporte Biológico/efeitos dos fármacos , Catalase/metabolismo , Cátions , Glutationa/metabolismo , Malondialdeído/análise , Osmorregulação/efeitos dos fármacos , Peroxidase/metabolismo , Phaseolus/química , Phaseolus/enzimologia , Phaseolus/metabolismo , Fotossíntese/efeitos dos fármacos , Potássio/análise , Prolina/metabolismo , Sódio/análise , Superóxido Dismutase/metabolismo
13.
Plant Sci ; 294: 110445, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32234228

RESUMO

Phosphate acquisition by plants is an essential process that is directly implicated in the optimization of crop yields. Purple acid phosphatases (PAPs) are ubiquitous metalloenzymes, which catalyze the hydrolysis of a wide range of phosphate esters and anhydrides. While some plant PAPs display a preference for ATP as the substrate, others are efficient in hydrolyzing phytate or 2-phosphoenolpyruvate (PEP). PAP from red kidney bean (rkbPAP) is an efficient ATP- and ADPase, but has no activity towards phytate. Crystal structures of this enzyme in complex with ATP analogues (to 2.20 and 2.60 Å resolution, respectively) complement the recent structure of rkbPAP with a bound ADP analogue (ChemBioChem 20 (2019) 1536). Together these complexes provide the first structural insight of a PAP in complex with molecules that mimic biologically relevant substrates. Homology modeling was used to generate three-dimensional structures for the active sites of PAPs from tobacco (NtPAP) and thale cress (AtPAP26) that are efficient in hydrolyzing phytate and PEP as preferred substrates, respectively. The combining of crystallographic data, substrate docking simulations and a phylogenetic analysis of 49 plant PAP sequences (including the first PAP sequences reported from Eucalyptus) resulted in the identification of several active site residues that are important in defining the substrate specificities of plant PAPs; of particular relevance is the identification of a motif ("REKA") that is characteristic for plant PAPs that possess phytase activity. These results may inform bioengineering studies aimed at identifying and incorporating suitable plant PAP genes into crops to improve phosphorus acquisition and use efficiency. Organic phosphorus sources increasingly supplement or replace inorganic fertilizer, and efficient phosphorus use of crops will lower the environmental footprint of agriculture while enhancing food production.


Assuntos
Fosfatase Ácida/metabolismo , Fosfatase Ácida/genética , Bioengenharia/métodos , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Phaseolus/genética , Phaseolus/metabolismo , Especificidade por Substrato
14.
Int J Mol Sci ; 21(6)2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32183068

RESUMO

Actin plays a critical role in the rhizobium-legume symbiosis. Cytoskeletal rearrangements and changes in actin occur in response to Nod factors secreted by rhizobia during symbiotic interactions with legumes. These cytoskeletal rearrangements are mediated by diverse actin-binding proteins, such as actin depolymerization factors (ADFs). We examined the function of an ADF in the Phaseolus vulgaris-rhizobia symbiotic interaction (PvADFE). PvADFE was preferentially expressed in rhizobia-inoculated roots and nodules. PvADFE promoter activity was associated with root hairs harbouring growing infection threads, cortical cell divisions beneath root hairs, and vascular bundles in mature nodules. Silencing of PvADFE using RNA interference increased the number of infection threads in the transgenic roots, resulting in increased nodule number, nitrogen fixation activity, and average nodule diameter. Conversely, overexpression of PvADFE reduced the nodule number, nitrogen fixation activity, average nodule diameter, as well as NODULE INCEPTION (NIN) and EARLY NODULIN2 (ENOD2) transcript accumulation. Hence, changes in ADFE transcript levels affect rhizobial infection and nodulation, suggesting that ADFE is fine-tuning these processes.


Assuntos
Fatores de Despolimerização de Actina/metabolismo , Phaseolus/metabolismo , Proteínas de Plantas/metabolismo , Rhizobium/metabolismo , Fatores de Despolimerização de Actina/genética , Fixação de Nitrogênio , Phaseolus/genética , Phaseolus/microbiologia , Proteínas de Plantas/genética , Rhizobium/genética
15.
J Environ Sci Health B ; 55(6): 517-524, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32065572

RESUMO

The current study estimated the dissipation rates of abamectin, chlorfenapyr and pyridaben acaricides in pods of green beans (Phaseolus vulgaris L.) under field conditions in Egypt. Pesticides were extracted and cleaned-up by QuEChERS method and were analyzed by HPLC. The dissipation of these acaricides followed the first order kinetics model with half-life (t1/2) values 1.00, 3.50 and 1.50 days for abamectin, chlorfenapyr and pyridaben, respectively. The lowest residues, at different time intervals of field application rate of each pesticide, were observed with abamectin followed by pyridaben and then chlorfenapyr. Pre-harvest intervals (PHIs) were 10.00, 13.50 and 6.00 days for abamectin, chlorfenapyr and pyridaben, respectively and were below the established European maximum residue limits (EU MRLs) 10-14, 14-21 and 7-10 days after application, respectively. If the fresh pods will be consumed after harvest, it is expected that the presence of these pesticides in the food will have a negative impact on human health. Therefore, the elimination of the residues of these harmful pesticides must be carried out.


Assuntos
Acaricidas/farmacocinética , Ivermectina/análogos & derivados , Phaseolus/efeitos dos fármacos , Piretrinas/farmacocinética , Piridazinas/farmacocinética , Acaricidas/análise , Fracionamento Químico , Cromatografia Líquida de Alta Pressão , Egito , Contaminação de Alimentos/análise , Humanos , Ivermectina/análise , Ivermectina/farmacocinética , Cinética , Resíduos de Praguicidas/análise , Phaseolus/metabolismo , Piretrinas/análise , Piridazinas/análise
16.
Sci Rep ; 10(1): 1680, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-32015448

RESUMO

The investigation of substrate spectrum towards five racemic (rac-) aryl glycidyl ethers (1a-5a) indicated that E. coli/pveh3, an E. coli BL21(DE3) transformant harboring a PvEH3-encoding gene pveh3, showed the highest EH activity and enantiomeric ratio (E) towards rac-3a. For efficiently catalyzing the kinetic resolution of rac-3a, the activity and E value of PvEH3 were further improved by site-directed mutagenesis of selected residues. Based on the semi-rational design of an NC-loop in PvEH3, four single-site variants of pveh3 were amplified by PCR, and intracellularly expressed in E. coli BL21(DE3), respectively. E. coli/pveh3E134K and /pveh3T137P had the enhanced EH activities of 15.3 ± 0.4 and 16.1 ± 0.5 U/g wet cell as well as E values of 21.7 ± 1.0 and 21.2 ± 1.1 towards rac-3a. Subsequently, E. coli/pveh3E134K/T137P harboring a double-site variant gene was also constructed, having the highest EH activity of 22.4 ± 0.6 U/g wet cell and E value of 24.1 ± 1.2. The specific activity of the purified PvEH3E134K/T137P (14.5 ± 0.5 U/mg protein) towards rac-3a and its catalytic efficiency (kcat/Km of 5.67 mM-1 s-1) for (S)-3a were 1.7- and 3.54-fold those (8.4 ± 0.3 U/mg and 1.60 mM-1 s-1) of PvEH3. The gram-scale kinetic resolution of rac-3a using whole wet cells of E. coli/pveh3E134K/T137P was performed at 20 °C for 7.0 h, producing (R)-3a with 99.4% ees and 38.5 ± 1.2% yield. Additionally, the mechanism of PvEH3E134K/T137P with remarkably improved E value was analyzed by molecular docking simulation.


Assuntos
Cresóis/metabolismo , Epóxido Hidrolases/metabolismo , Compostos de Epóxi/metabolismo , Phaseolus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Catálise , Epóxido Hidrolases/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Cinética , Simulação de Acoplamento Molecular/métodos , Mutagênese Sítio-Dirigida/métodos , Phaseolus/genética , Estereoisomerismo , Especificidade por Substrato/fisiologia
17.
Ecotoxicol Environ Saf ; 190: 110178, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31927193

RESUMO

Given the limitation of crop production in Cd-polluted areas, the identification and selection of plant genotypes tolerant to Cd stress are of great significance. In the present work, we show the existence of genotypic variation for Cd tolerance in common bean. The laboratory screening of 25 bean genotypes indicated a significant positive correlation of the mean productivity (MP) and the geometric mean productivity (GMP) with plant fresh weight both in control and Cd-treated plants. A principal component analysis further confirmed this variation and, together with other analyses, led to the selection of genotypes G-11867, Taylor, Emerson, and D-81083 as tolerant genotypes. A total of six bean genotypes with different degrees of Cd tolerance were selected, and their long-term physiological responses to Cd (0, 45, and 90 mg/kg soil) were evaluated. Increasing Cd concentrations led to higher Cd accumulation both in roots and shoots, and to significant rises in the levels of the oxidative stress biomarkers malondialdehyde (MDA), dityrosine (D-T), and 8-hydroxy-2'-deoxyguanosine (8-OH-2'-dG). Remarkable reductions in plant hormone levels and chlorophyll contents, as well as in dry and fresh weight, were observed in Cd-treated plants. Among the examined genotypes, Emerson, Taylor, and G-11867 were found to be more tolerant to Cd owing to lower Cd accumulation and lower oxidative stress levels, as well as higher chlorophyll and hormone contents. Our results contribute to the understanding of the physiological and biochemical basis of Cd tolerance in bean plants and may therefore, be useful for breeding programs directed towards obtaining bean varieties showing low Cd accumulation.


Assuntos
Aclimatação/genética , Cádmio/toxicidade , Phaseolus/efeitos dos fármacos , Poluentes do Solo/toxicidade , 8-Hidroxi-2'-Desoxiguanosina/metabolismo , Clorofila/metabolismo , Genótipo , Malondialdeído/metabolismo , Phaseolus/genética , Phaseolus/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/genética , Brotos de Planta/metabolismo , Estresse Fisiológico/genética , Tirosina/análogos & derivados , Tirosina/metabolismo
18.
Plant Mol Biol ; 102(4-5): 431-445, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31907707

RESUMO

KEY MESSAGE: Iron deficiency conditions as well as iron supplied as a Fe(III)-mimosine complex induced a number of strategy I and strategy II genes for iron uptake in leucaena. Leucaena leucocephala (leucaena) is a tree-legume that can grow in alkaline soils, where metal-cofactors like Fe(III) are sparingly available. Mimosine, a known chelator of Fe(III), may facilitate Fe(III) uptake in leucaena by serving as a phytosiderophore. To test if mimosine can serve as a phytosiderophore, three sets of experiments were carried out. First, the binding properties and solubility of metal-mimosine complexes were assessed through spectrophotometry. Second, to study mimosine uptake in plants, pole bean, common bean, and tomato plants were supplied with mimosine alone and metal-mimosine complexes. Third, the expression of strategy I (S1) and strategy II (S2) genes for iron uptake from the soil was studied in leucaena plants exposed to different Fe(III) complexes. The results of this study show that (i) mimosine has high binding affinity for metallic cations at alkaline pH, Fe(III)-mimosine complexes are water soluble at alkaline pH, and that mimosine can bind soil iron under alkaline pH; (ii) pole bean, common bean, and tomato plants can uptake mimosine and transport it throughout the plant; and (iii) a number of S1 and S2 genes were upregulated in leucaena under iron-deficiency condition or when Fe(III) was supplied as a Fe(III)-mimosine complex. These findings suggest that leucaena may utilize both S1 and S2 strategies for iron uptake; and mimosine may play an important role in both strategies.


Assuntos
Fabaceae/efeitos dos fármacos , Fabaceae/metabolismo , Mimosina/farmacocinética , Transporte Biológico , Tampões (Química) , Cátions , Compostos Férricos/metabolismo , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ferro/metabolismo , Metais/metabolismo , Nitrogênio , Phaseolus/efeitos dos fármacos , Phaseolus/metabolismo , Folhas de Planta/metabolismo , Caules de Planta/metabolismo , Ligação Proteica , Sideróforos/metabolismo , Solo , Solanum/efeitos dos fármacos , Solanum/metabolismo , Solubilidade
19.
J Agric Food Chem ; 68(4): 1091-1100, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31896257

RESUMO

The physical structure of type 1 resistant starch (RS 1) could influence the metabolite production and stimulate the growth of specific bacteria in the human colon. In the present study, we isolated intact cotyledon cells from pinto bean seeds as whole pulse food and RS 1 model and obtained a series of cell wall integrities through controlled enzymolysis. In vitro human fecal fermentation performance and microbiota responses were tested, and we reported that the cell wall integrity controls the in vitro fecal fermentation rate of heat-treated pinto bean cells. The concentration of butyrate produced by pinto bean cell fermentation enhanced with weakened cell wall integrity, and certain beneficial bacterial groups such as Blautia and Roseburia genera were remarkably promoted by pinto bean cells with damaged cell wall integrity. However, the intact cell sample had a shape more similar to microbiota composition with the purified cell wall polysaccharides, rather than the damaged cells.


Assuntos
Bactérias/metabolismo , Parede Celular/metabolismo , Fezes/microbiologia , Microbioma Gastrointestinal , Phaseolus/metabolismo , Bactérias/química , Bactérias/classificação , Bactérias/isolamento & purificação , Parede Celular/química , Fermentação , Humanos , Phaseolus/química , Polissacarídeos/metabolismo , Sementes/química , Sementes/metabolismo
20.
Antonie Van Leeuwenhoek ; 113(5): 687-696, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31900709

RESUMO

Hydrogen-uptake (Hup) activity is implicated in the mitigation of energy losses associated with the biological nitrogen fixation process, and has been related to productivity increases in some legume hosts. However, in common bean (Phaseolus vulgaris L.) the expression of hydrogenase is rare. In this study an 18-kb hup gene cluster from Rhizobium leguminosarum bv. viciae encoding a NiFe hydrogenase was successfully transferred to three common bean rhizobial strains lacking hydrogenase activity (Hup-) but symbiotically very effective and used in commercial inoculants in Brazil: one strain originally from Colombia (Rhizobium tropici CIAT 899), and two strains from Brazil (R. tropici H 12 and Rhizobium freirei PRF 81). The inclusion of NiCl2 in the nutrient solution did not increase hydrogenase activity, indicating that common bean plants allow efficient nickel provision for hydrogenase synthesis in the bacteroids. The symbiotic performance-evaluated by nodulation, plant growth, N accumulation and seed production-of wild-type and Hup+ derivative strains was compared in experiments performed with cultivar Carioca under greenhouse conditions, in sterile substrate and in non-sterile soil. Statistically significant increases in one or more parameters were observed for all three Hup+ derivatives when compared to the respective wild-type strain. Differences were found mainly with the Brazilian strains, reaching impressive increases in nodule efficiency and seed total N content. The results highlight the potential of using Rhizobium Hup+ strains for the design of more energy-efficient inoculants for the common bean crop.


Assuntos
Hidrogenase/genética , Phaseolus , Plantas Geneticamente Modificadas , Rhizobium/genética , Proteínas de Bactérias/genética , Brasil , Genes Bacterianos , Hidrogênio/metabolismo , Nitrogênio/metabolismo , Fixação de Nitrogênio/genética , Phaseolus/crescimento & desenvolvimento , Phaseolus/metabolismo , Phaseolus/microbiologia , Nódulos Radiculares de Plantas/genética , Simbiose/genética
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