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1.
J Agric Food Chem ; 68(1): 384-389, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31804818

RESUMO

Our previous research showed that thioacetal and Schiff base formed between 5-hydroxymethylfurfural (HMF) and cysteine or lysine considerably decreased the cytotoxicity of HMF. In this study, two adol condensation adducts, named 2ß-amino-3α-hydroxy-3-(5-(hydroxymethyl)furan-2-yl)propanoic acid (HGA) and 2α-amino-3ß-hydroxy-3-(5-(hydroxymethyl)furan-2-yl)propanoic acid (HGB), were prepared from the reaction products of glycine and HMF, and their cytotoxicities were investigated in Caco-2 cells. Compared with HMF, HGA and HGB displayed lower cytotoxicities against Caco-2 cells with IC50 values of 36.50 and 43.47 mM, respectively, versus 16.11 mM (HMF). In contrast to our findings in thioacetal and Schiff base products, HGA and HGB underwent a very high metabolism rate (99%) in Caco-2 cells. HGA and HGB may degrade to other products instead of HMF since no extracellular or intracellular HMF was detected.


Assuntos
Furaldeído/análogos & derivados , Glicina/química , Glicina/toxicidade , Adsorção , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Furaldeído/química , Furaldeído/metabolismo , Furaldeído/toxicidade , Glicina/metabolismo , Temperatura Alta , Humanos
2.
Food Chem Toxicol ; 135: 110888, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31629789

RESUMO

Glyphosate is used for cereal, vegetable and fruit crops for reducing or inhibiting the growth of weeds as well as a desiccant for various grain crops. That is why, glyphosate has been shown to be accumulated in humans and animals through ingestion of food of both plant and animal origin. The study aimed to assessed the effect of glyphosate, its metabolites: aminomethylphosphonic acid (AMPA), methylphosphonic acid and its impurities: PMIDA, N-methylglyphosate, hydroxymethylphosphonic acid and bis(phosphonomethyl)amine on apoptosis induction in human peripheral blood mononuclear cells (PBMCs). PBMCs were exposed to the compounds studied at the concentrations ranging from 0.01 to 5 mM for 4 h. We have observed an increase in reactive oxygen species (including hydroxyl radical) and cytosolic calcium ions levels as well as reduction of transmembrane mitochondrial potential (ΔΨm) in PBMCs exposed to the compounds examined. All substances studied changed PBMCs membrane permeability, activated caspase-8, -9, -3 and caused chromatin condensation, which showed that they were capable of inducing apoptosis both via extrinsic and particularly intrinsic pathway. Generally the study demonstrated that there were no differences between apoptotic changes induced by glyphosate, its metabolites or impurities, and observed changes were provoked by high concentrations of investigated compounds.


Assuntos
Apoptose/efeitos dos fármacos , Glicina/análogos & derivados , Herbicidas/toxicidade , Monócitos/efeitos dos fármacos , Cálcio/sangue , Caspases/metabolismo , Cromatina/metabolismo , Ativação Enzimática , Glicina/metabolismo , Glicina/toxicidade , Herbicidas/metabolismo , Humanos , Radical Hidroxila/metabolismo , Técnicas In Vitro , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Monócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo
3.
J Agric Food Chem ; 67(48): 13247-13257, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31707781

RESUMO

Dietary interventions alter the formation of the disease-associated metabolite, trimethylamine (TMA), via intestinal microbial TMA lyase activity. Nevertheless, the mechanisms regulating microbial enzyme production are still unclear. Sequencing of the gut bacteria 16S rDNA demonstrated that dietary intervention changed the composition of the gut microbiota and the functional metagenome involved in the choline utilization pathway. Characterization of the functional profile of the metagenomes and metabonomics analysis revealed that a series of Kyoto Encyclopedia of Genes and Genomes orthologous groups and enzyme groups related to accumulation of methylglyoxal (MG) and glycine were enriched in red meat diet-fed animals, whereas fiber-rich diet suppressed glycine formation via the MG-dependent pathway. Our observations suggest associations between choline-TMA lyase expression and MG formation, which are indicative of a novel role of the gut microbiota in choline metabolism and highlight it as a potential target for inhibiting TMA production.


Assuntos
Bactérias/metabolismo , Colina/metabolismo , Fibras na Dieta/metabolismo , Microbioma Gastrointestinal , Metilaminas/metabolismo , Aldeído Pirúvico/metabolismo , Ração Animal/análise , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/microbiologia , Glicina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Carne Vermelha/análise
4.
Microb Cell Fact ; 18(1): 194, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699086

RESUMO

BACKGROUND: 5'-Aminolevulinic acid (ALA) is widely used in the pharmaceutical industry, healthcare, and food production, and is a substrate for the biosynthesis of heme, which is required for respiration and photosynthesis. Enhancement of ALA biosynthesis has never been developed in Saccharomyces cerevisiae, which is a well-known model microorganism used for bioproduction of many value-added compounds. RESULTS: We demonstrated that metabolic engineering significantly improved ALA production in S. cerevisiae. First, we found that overexpression of HEM1, which encodes ALA synthetase, increased ALA production. Furthermore, addition of an optimal amount of glycine, a substrate for ALA biosynthesis, or levulinic acid, an inhibitor of ALA dehydrogenase, effectively increased ALA production. Next, we developed an assay for multiple metabolites including ALA and found that aconitase, encoded by ACO1 and ACO2, is the rate-limiting enzyme of ALA biosynthesis when sufficient glycine is supplied. Overexpression of ACO2 further enhanced ALA production in S. cerevisiae overexpressing HEM1. CONCLUSIONS: In this study, ALA production in S. cerevisiae was enhanced by metabolic engineering. This study also shows a strategy to identify the rate-limiting step of a target synthetic pathway by assay for multiple metabolites alongside the target product. This strategy can be applied to improve production of other valuable products in the well-studied and well-industrialized microorganism S. cerevisiae.


Assuntos
Ácidos Levulínicos/metabolismo , Engenharia Metabólica/métodos , Organismos Geneticamente Modificados/metabolismo , Saccharomyces cerevisiae , Aconitato Hidratase/genética , Aconitato Hidratase/metabolismo , Fermentação , Glicina/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
5.
Plant Physiol Biochem ; 144: 395-403, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31629224

RESUMO

Sweetpotato (Ipomoea batatas Lam.) plays an indispensable role in feed, starch-based industries and ethanol biofuel production. Few studies have investigated on how external amino acids affect the growth and production of sweetpotato. In the study, we evaluated morphological, physiological and molecular effects of external glycine (Gly) on the root growth and starch metabolism of sweetpotato, Xushu16. At morphological level, the Xushu16 with Gly stimuli had larger plant biomass than that under control condition. At physiological level, the photosynthesis strength of the Xushu16 with Gly treatments showed significant differences relative to those under control condition. The relative content of plant hormone and starch in storage roots was higher under Gly conditions than that under control condition. At molecular level, a total of 4836 differentially expression genes were identified in the storage roots with different Gly treatments by RNA-Seq. Among them, as many as 1830 genes were involved in carbohydrate metabolism, which held maximum proportion among all the DEGs. Further, a few genes involved in starch biosynthesis were proved to be Gly-induced significantly by RT-qPCR. All the results indicated extrinsic Gly promotes the growth of storage roots by strengthening photosynthesis and increasing plant hormone, and enhances starch biosynthesis of storage roots by accelerating carbohydrate metabolism and regulating the expression of starch-related genes.


Assuntos
Glicina/metabolismo , Ipomoea batatas/metabolismo , Raízes de Plantas/metabolismo , Amido/metabolismo , Regulação da Expressão Gênica de Plantas
6.
BMC Res Notes ; 12(1): 494, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31395095

RESUMO

OBJECTIVES: Glyphosate (N-phosphonomethyl glycine) and its commercial herbicide formulations have been shown to exert toxicity via various mechanisms. It has been asserted that glyphosate substitutes for glycine in polypeptide chains leading to protein misfolding and toxicity. However, as no direct evidence exists for glycine to glyphosate substitution in proteins, including in mammalian organisms, we tested this claim by conducting a proteomics analysis of MDA-MB-231 human breast cancer cells grown in the presence of 100 mg/L glyphosate for 6 days. Protein extracts from three treated and three untreated cell cultures were analysed as one TMT-6plex labelled sample, to highlight a specific pattern (+/+/+/-/-/-) of reporter intensities for peptides bearing true glyphosate treatment induced-post translational modifications as well as allowing an investigation of the total proteome. RESULTS: Comparative statistical analysis of global proteome changes between glyphosate treated and non-treated samples did not show significant differences. Crucially, filtering of data to focus analysis on peptides potentially bearing glycine for glyphosate replacement revealed that the TMT reporter intensity pattern of all candidates showed conclusively that they are all false discoveries, with none displaying the expected TMT pattern for such a substitution. Thus, the assertion that glyphosate substitutes for glycine in protein polypeptide chains is incorrect.


Assuntos
Glicina/análogos & derivados , Glicina/metabolismo , Herbicidas/química , Proteínas de Neoplasias/metabolismo , Processamento de Proteína Pós-Traducional , Proteoma/metabolismo , Linhagem Celular Tumoral , Expressão Gênica , Glicina/química , Glicina-tRNA Ligase/química , Glicina-tRNA Ligase/genética , Glicina-tRNA Ligase/metabolismo , Herbicidas/metabolismo , Humanos , Modelos Moleculares , Proteínas de Neoplasias/genética , Proteoma/genética
7.
Microb Pathog ; 135: 103636, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31377236

RESUMO

Plants deploy RNA silencing as a natural defence against invading viruses involving sequence-specific degradation of the viral RNAs. As a counter-defence strategy, viruses encode suppressor proteins that simultaneously target different steps of the silencing machinery. Tomato leaf curl Palampur virus (ToLCPalV) is a bipartite begomovirus in Geminiviridae family. It is responsible for significant reduction in the crop yield and quality. DNA-A of the virus encodes for six proteins whereas DNA-B codes for two proteins. In this study, all viral genes were screened for their role in suppression of green fluorescent protein (GFP) silencing in Nicotiana tabacum cv. Xanthi, employing agrobacterium based co-infiltration assay. The assay identified AC4 as a potential suppressor of RNA silencing. In addition, AC4 expression also suppressed virus-induced gene silencing (VIGS) of the phytoene desaturase (PDS) gene in N. benthamiana. Potato virus X (PVX) mediated transient expression of the AC4 in N. benthamiana showed enhanced symptoms that include downward leaf curling, leaf puckering and tissue necrosis. Further, N. benthamiana lines stably expressing AC4 showed severe developmental abnormalities. Mutational analysis suggested that glycine at 2nd position is essential for AC4 pathogenicity. Collectively, these findings demonstrate the role of ToLCPalV AC4 in viral pathogenesis, disease establishment and suppression of gene silencing.


Assuntos
Begomovirus/metabolismo , Doenças das Plantas/virologia , Interferência de RNA/fisiologia , RNA Viral/metabolismo , Proteínas Virais/metabolismo , Begomovirus/genética , Coinfecção , Regulação Viral da Expressão Gênica , Genes Virais , Glicina/metabolismo , Proteínas de Fluorescência Verde , Oxirredutases/genética , Mutação Puntual , Potexvirus , Tabaco/virologia , Proteínas Virais/genética , Virulência
8.
Gen Physiol Biophys ; 38(5): 399-406, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31411570

RESUMO

The substantia gelatinosa of the trigeminal subnucleus caudalis has been considered to be an essential location for the transference of orofacial sensory signals. The co-localization of inhibitory and excitatory neurotransmitters in the same substantia gelatinosa (SG) neurons has demonstrated their essential part in the modification of nociceptive transmission. Zn2+ is particularly numerous in the mammalian central nervous system. There are proofs demonstrating the role of Zn2+ in the modulation of voltage- and ligand-gated ion channels. However, little is known about what roles Zn2+ may play in the modulation of signal transmission in the SG neurons of the trigeminal subnucleus caudalis (Vc). Therefore, in this study, we used the whole-cell patch clamp technique to find out the effect of Zn2+ on the responses of three main neurotransmitters (glycine, GABA, and glutamate) on SG neurons of the Vc in mice. We have proved that Zn2+ induces a big potentiation of glycine receptor-mediated response but attenuates GABA- and glutamate-induced responses at micromolar concentrations, however, enhances glutamate-induced response at nanomolar concentration. Taken together, these data demonstrated that Zn2+ can modulate glycine, GABA and glutamate-mediated actions on the SG neurons of the Vc and support an important mechanism in spinal sensory information signaling.


Assuntos
Neurônios/efeitos dos fármacos , Substância Gelatinosa/citologia , Transmissão Sináptica/efeitos dos fármacos , Zinco/farmacologia , Animais , Ácido Glutâmico/metabolismo , Glicina/metabolismo , Camundongos , Neurotransmissores/metabolismo , Técnicas de Patch-Clamp , Ratos Sprague-Dawley , Receptores da Glicina/metabolismo , Ácido gama-Aminobutírico/metabolismo
9.
J Agric Food Chem ; 67(36): 10010-10017, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31414816

RESUMO

Dominican farmers have started to apply synthetic auxin herbicides (SAHs) as the main alternative to mitigate the impacts of the occurrence of glyphosate-resistant (GR) Parthenium hysterophorus populations in citrus orchards. A GR P. hysterophorus population survived field labeled rates of glyphosate, 2,4-dichlorophenoxyacetic acid (2,4-D), dicamba, and picloram, which showed poor control (<50%). In in vivo assays, resistance levels were high for glyphosate and moderate for picloram, dicamba, and 2,4-D. Sequencing the 5-enolpyruvylshikimate-3-phosphate synthase gene revealed the double Thr-102-Ile and Pro-106-Ser amino acid substitution, conferring resistance to glyphosate. Additionally, reduced absorption and impaired translocation contributed to this resistance. Regarding SAH, impaired 2,4-D transport and enhanced metabolism were confirmed in resistant plants. The application of malathion improved the efficacy of SAHs (control >50%), showing that metabolism of these herbicides was mediated by cytochrome P450 enzymes. This study reports, for the first time, multiple resistance to SAHs and glyphosate in P. hysterophorus.


Assuntos
Asteraceae/efeitos dos fármacos , Citrus/crescimento & desenvolvimento , Glicina/análogos & derivados , Resistência a Herbicidas , Herbicidas/farmacologia , Ácidos Indolacéticos/farmacologia , Ácido 2,4-Diclorofenoxiacético/metabolismo , Ácido 2,4-Diclorofenoxiacético/farmacologia , Asteraceae/metabolismo , Dicamba/metabolismo , Dicamba/farmacologia , Glicina/metabolismo , Glicina/farmacologia , Herbicidas/metabolismo , Ácidos Indolacéticos/metabolismo
10.
Biochem Mol Biol Educ ; 47(6): 689-699, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31444933

RESUMO

Protein engineering represents a modern approach to generate novel proteins for the different fields of biotechnology. Here, we report about an 8-day laboratory activity in which students generate enzyme variants to degrade the herbicide glyphosate. The students conduct a true research experiment in an important field (bioremediation by novel, engineered enzymes) and are introduced to widely used techniques in molecular biology and protein biochemistry laboratories. Based on a docking analysis of glycine (the original substrate) and of glyphosate into the active site of glycine oxidase, residues putatively involved in substrate selectivity are identified that will become the target of site-saturation mutagenesis. Each group of students focuses on the library generated at one position and selects the most active variant based on colorimetric screening. Following protein overexpression in Escherichia coli, the selected glycine oxidase variants are purified and their kinetic properties on glycine and glyphosate assessed. The best variant identified by the whole class is then used for detecting the herbicide in water. With the help of the professor, students can improve technical skills, ability to evaluate results, team work activity, and critical thinking. © 2019 International Union of Biochemistry and Molecular Biology, 47(6):689-699, 2019.


Assuntos
Aminoácido Oxirredutases/metabolismo , Glicina/análogos & derivados , Herbicidas/metabolismo , Laboratórios , Engenharia de Proteínas , Aminoácido Oxirredutases/química , Bioquímica/educação , Domínio Catalítico , Currículo , Glicina/química , Glicina/metabolismo , Herbicidas/química , Humanos , Biologia Molecular/educação , Simulação de Acoplamento Molecular , Estrutura Molecular , Estudantes
11.
Neurodiagn J ; 59(3): 142-151, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31433733

RESUMO

Nonketotic hyperglycinemia (NKH) or glycine encephalopathy is an autosomal recessive disorder of glycine metabolism resulting in an excessive accumulation of glycine in all body tissues, including the central nervous system. It is caused by a biochemical defect in the glycine cleavage system and considered as a rare disorder with an estimated prevalence of 1:60,000. The neonatal form presents in the first few days of life with progressive encephalopathy, hypotonia, myoclonic jerks, hiccups, seizures, rapid progression to coma and often death due to central apnea. Surviving infants often have severe developmental delay and refractory seizures. Atypical forms of NKH present with heterogeneous and nonspecific disease course. Classical glycine encephalopathy usually carries a very poor prognosis. We describe two neonates who presented with neonatal encephalopathy, apnea, and progressive lethargy. Increased CSF glycine level along with an elevated CSF to plasma glycine ratio was suggestive of classic NKH. Burst suppression EEG and agenesis of the corpus callosum were supportive findings. Evolution of the EEG patterns and course of the disease are discussed in detail. Transient phases of clinical stabilization and normalized plasma biochemical results may not necessarily reflect the actual encephalopathic process. Serial EEGs are helpful to assess the efficacy of treatment and to modify the therapeutic approach.


Assuntos
Hiperglicinemia não Cetótica/diagnóstico , Agenesia do Corpo Caloso/diagnóstico por imagem , Agenesia do Corpo Caloso/etiologia , Apneia/etiologia , Encéfalo/diagnóstico por imagem , Encefalopatias/etiologia , Eletroencefalografia , Evolução Fatal , Feminino , Glicina/líquido cefalorraquidiano , Glicina/metabolismo , Humanos , Hiperglicinemia não Cetótica/diagnóstico por imagem , Recém-Nascido , Imagem por Ressonância Magnética , Masculino , Convulsões/etiologia , Convulsões/terapia , Estado Epiléptico/etiologia
12.
PLoS Biol ; 17(8): e3000371, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31433808

RESUMO

Inhibitory glycinergic transmission in adult spinal cord is primarily mediated by glycine receptors (GlyRs) containing the α1 subunit. Here, we found that α1ins, a longer α1 variant with 8 amino acids inserted into the intracellular large loop (IL) between transmembrane (TM)3 and TM4 domains, was expressed in the dorsal horn of the spinal cord, distributed at inhibitory synapses, and engaged in negative control over nociceptive signal transduction. Activation of metabotropic glutamate receptor 5 (mGluR5) specifically suppressed α1ins-mediated glycinergic transmission and evoked pain sensitization. Extracellular signal-regulated kinase (ERK) was critical for mGluR5 to inhibit α1ins. By binding to a D-docking site created by the 8-amino-acid insert within the TM3-TM4 loop of α1ins, the active ERK catalyzed α1ins phosphorylation at Ser380, which favored α1ins ubiquitination at Lys379 and led to α1ins endocytosis. Disruption of ERK interaction with α1ins blocked Ser380 phosphorylation, potentiated glycinergic synaptic currents, and alleviated inflammatory and neuropathic pain. These data thus unraveled a novel, to our knowledge, mechanism for the activity-dependent regulation of glycinergic neurotransmission.


Assuntos
Células do Corno Posterior/metabolismo , Receptores da Glicina/metabolismo , Animais , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Glicina/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína Quinase 7 Ativada por Mitógeno/metabolismo , Fosforilação , Receptor de Glutamato Metabotrópico 5/metabolismo , Receptor de Glutamato Metabotrópico 5/fisiologia , Receptores da Glicina/fisiologia , Transdução de Sinais/fisiologia , Medula Espinal/metabolismo , Corno Dorsal da Medula Espinal/metabolismo , Coluna Vertebral/metabolismo , Sinapses/metabolismo , Transmissão Sináptica/fisiologia
13.
J Ind Microbiol Biotechnol ; 46(12): 1685-1695, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31420796

RESUMO

Glutathione is a bioactive tripeptide composed of glycine, L-cysteine, and L-glutamate, and has been widely used in pharmaceutical, food, and healthy products. The current metabolic studies of glutathione were mainly focused on the native producing strains with precursor amino acid supplementation. In the present work, Corynebacterium glutamicum, a workhorse for industrial production of a series of amino acids, was engineered to produce glutathione. First, the introduction of glutathione synthetase gene gshF from Streptococcus agalactiae fulfilled the ability of glutathione production in C. glutamicum and revealed that L-cysteine was the limiting factor. Then, considering the inherent capability of L-glutamate synthesis and the availability of external addition of low-cost glycine, L-cysteine biosynthesis was enhanced using a varieties of pathway engineering methods, such as disrupting the degradation pathways of L-cysteine and L-serine, and removing the repressor responsible for sulfur metabolism. Finally, the simultaneously introduction of gshF and enhancement of cysteine formation enabled C. glutamicum strain to produce glutathione greatly. Without external addition of L-cysteine and L-glutamate, 756 mg/L glutathione was produced. This is first time to demonstrate the potential of the glutathione non-producing strain C. glutamicum for glutathione production and provide a novel strategy to construct glutathione-producing strains.


Assuntos
Corynebacterium glutamicum/metabolismo , Glutationa/biossíntese , Corynebacterium glutamicum/genética , Cisteína/metabolismo , Ácido Glutâmico/metabolismo , Glicina/metabolismo , Engenharia Metabólica/métodos , Redes e Vias Metabólicas , Serina/metabolismo
14.
Sci Total Environ ; 695: 133859, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31421347

RESUMO

Uptake of nanoparticles and antibiotics by plants is root exudates-dependent, however, the underlying influence processes and mechanisms from different root exudates are rarely investigated. A hydroponic experiment was conducted to investigate the accumulation of Fe2O3 nanoparticle (NP) and oxytetracycline (OTC) in rice seedlings, in the absence or presence of citric acid or glycine, acting as components of root exudates. Irrespective of individual or combined exposure of Fe2O3 NP and OTC, citric acid and glycine both reduced surface-Fe, surface-OTC, root-OTC, shoot-OTC accumulations with dose-effect relationship. Two exudates increased |ζ| values of NP, which weakened the interactive attraction between NP and root surface and then decreased surface-Fe accumulation. Citric acid and glycine binding with OTC in solution decreased surface-OTC accumulation, and further decreased root-OTC and shoot-OTC accumulations. Combined exposure of two pollutants alleviated the reduction effect of citric acid and glycine on surface-Fe/surface-OTC/root-OTC accumulations due to their high accumulations in combined exposure compared to individual exposure. Although citric acid and glycine promoted TFroot-shoot and TFsurface-root of two pollutants, respectively, they always decreased total rice-Fe and rice-OTC accumulations. Therefore, the presence of root exudates decreased the bioaccumulation of Fe2O3 NP and OTC in rice upon their individual and combined exposure through changing their environmental behaviors in rhizosphere.


Assuntos
Ácido Cítrico/metabolismo , Compostos Férricos/metabolismo , Glicina/metabolismo , Nanopartículas/metabolismo , Oryza/fisiologia , Poluentes do Solo/metabolismo , Oxitetraciclina , Plântula
15.
J Sci Food Agric ; 99(15): 6911-6921, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31393604

RESUMO

BACKGROUND: This study aimed to evaluate the possibility of cotton waste enrichment with glycine betaine (GB) for production of two strains (P9, P10) of king oyster (Pleurotus eryngii). Cotton waste was used as (100%) control (T0 = cotton waste) and augmented with various combinations of GB, (T1 = 2 mmol L-1 , T2 = 4 mmol L-1 , T3 = 6 mmol L-1 , T4 = 8 mmol L-1 and T5 = 10 mmol L-1 ). The response of king oyster to GB was evaluated by earliness, yield, biological efficiency (BE), minerals (nitrogen, phosphorus, potassium, zinc (Zn), copper (Cu), magnesium (Mg), manganese (Mn), iron (Fe), sodium (Na), calcium (Ca)), total sugars, total soluble solids, reducing sugars, non-reducing sugars, ascorbic acid, proximate (crude protein, carbohydrates, crude fibers, ash, fats) content of fruiting body and Fourier-transform infrared (FTIR) spectroscopy analysis compared with the control substrate (cotton waste). RESULTS: The earliness, yield, and BE were higher as compared to control substrate and increased with an augmentation in the concentration of GB within the cotton waste. Two strains showed (on dry weight basis) 33.9-54.9 mg g-1 nitrogen, 6.8-12.5 mg g-1 phosphorus, 16.9-25.1 mg g-1 potassium, 40.5-64.2 mg kg-1 Zn, 17.1-37.3 mg kg-1 Cu, 1174-1325 mg kg-1 Mg, 20.1-29.1 mg kg-1 Mn, 129-265 mg kg-1 Fe, 779-835 mg kg-1 Ca), 6.3%-11.3% total sugars, 7.3-14.9 °Brix total soluble solids, 2.1-7.3% reducing sugars, 10.4-18.1% crude protein, 3.6-4.4% crude fiber and 5.6-16.7 mg (100 g)-1 on various concentration of GB enrich cotton waste. Cotton waste enriched with GB significantly affected nutritional profile of king oyster mushroom. CONCLUSION: The results revealed that GB enriched cotton waste can be used as an innovative substrate to enhance the yield and quality of king oyster mushroom. © 2019 Society of Chemical Industry.


Assuntos
Betaína/metabolismo , Meios de Cultura/metabolismo , Glicina/metabolismo , Gossypium/microbiologia , Pleurotus/química , Pleurotus/metabolismo , Resíduos/análise , Betaína/análise , Meios de Cultura/química , Glicina/análise , Gossypium/metabolismo , Minerais/metabolismo , Nitrogênio/análise , Nitrogênio/metabolismo , Fósforo/análise , Fósforo/metabolismo , Pleurotus/genética , Pleurotus/crescimento & desenvolvimento
16.
Pestic Biochem Physiol ; 159: 22-26, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31400780

RESUMO

Herbicide efficacy depends on herbicides crossing cell and organelle membranes. We evaluated an artificial membrane system to understand how herbicides cross biological membranes. This understanding aids in predicting herbicide behavior in planta and, consequently, efficacy, mode of action, and whether active transporter-based herbicide resistance mechanisms may be possible. Five herbicides with different log Kow and pKa values were assessed: glyphosate, 2,4-D, clopyralid, sulfentrazone and glufosinate. The artificial membrane apparatus included four semipermeable membranes containing buffers with pH 2.7, 5 and/or 7.4, floating in a bath of diethyl ether. These conditions were based on the pH from different cellular compartments and the pKa for these herbicides. Changes in herbicide concentration due to movement were measured using radioactivity or liquid chromatography mass spectrometry. In general, herbicide behavior followed the pattern predicted by their calculated pKa and log Kow. Herbicides added to an acidic phase (pH 2.7) were more mobile than when they were added to the more basic phase (pH 7.4), except when herbicide's pKa was lower than the pH of the starting phase. Clopyralid, 2,4-D, and sulfentrazone showed significant acid trapping behavior due to their weak acid functional groups. Sulfentrazone and 2,4-D had a high affinity for the nonpolar, diethyl ether bath, especially when they were protonated at low pH. Our findings illustrate the robustness of the system to provide predictions about herbicide behavior at the subcellular level.


Assuntos
Herbicidas/metabolismo , Ácido 2,4-Diclorofenoxiacético/metabolismo , Aminobutiratos/metabolismo , Glicina/análogos & derivados , Glicina/metabolismo , Concentração de Íons de Hidrogênio , Membranas Artificiais , Ácidos Picolínicos/metabolismo , Sulfonamidas/metabolismo , Triazóis/metabolismo
17.
Artigo em Inglês | MEDLINE | ID: mdl-31287383

RESUMO

A method has been developed for the rapid, specific, accurate, precise and sensitive determination of glufosinate, glyphosate and its major metabolite, aminomethylphosphonic acid, in edible oils, by liquid chromatography coupled to tandem mass spectrometry. Oils were extracted with acidified water (1% formic acid), and the extracts were directly injected into an LC using a Hypercarb column as the stationary phase. The analytes were eluted by a mobile phase of methanol and water containing 1% acetic acid, and they were ionised by electrospray ionisation in negative ion mode. The method was validated and limits of quantification ranged from 5 µg kg-1 (aminomethylphosphonic acid) to 10 µg kg-1 (glyphosate and glufosinate). Three concentrations (10, 50 and 100 µg kg-1) were selected to perform recovery studies. Mean recoveries ranged from 81.4% to 119.4%. Intra and inter-day precision were lower than 19%. Different edible oils were analysed, and no residues of the studied herbicides were detected above limits of quantification.


Assuntos
Aminobutiratos/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Glicina/análogos & derivados , Isoxazóis/análise , Óleos Vegetais/análise , Espectrometria de Massas em Tandem , Tetrazóis/análise , Aminobutiratos/metabolismo , Cromatografia Líquida , Glicina/análise , Glicina/metabolismo , Isoxazóis/metabolismo , Óleos Vegetais/metabolismo , Tetrazóis/metabolismo
18.
J Plant Physiol ; 240: 153009, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31330417

RESUMO

Influence of low temperatures on the glyphosate efficacy was studied in glyphosate-resistant (R) and -susceptible (S) Conyza sumatrensis biotypes. For this purpose, the physiological and enzymatic aspects involved were characterized under two growing temperature regimes [high (30/20 °C) and low 15/5 °C temperatures day/night]. The R biotype was 5.5 times more resistant than the S biotype at high temperatures; however, this R-to-S ratio decreased to 1.6 at low temperatures. At 96 h after treatment (HAT), the shikimic acid accumulation was higher in the S biotype in both temperature regimes (4.6 and 1.9 more shikimic acid at high and low temperatures, respectively), but the accumulation of the R biotype increased 2.6 times at low temperatures compared to high ones. From 24 to 96 HAT, the 14C-glyphosate absorption ranged from 28 to 65% (percentage reached from 48 HAT) at low temperatures, and from 20 to 50% at high temperatures (gradual increase), but there were no differences between C. sumatrensis biotypes within each temperature regime. At high temperatures, the 14C-glyphosate translocation was different between biotypes, where the R one retained at least 10% more herbicide in the treated leaves than the S biotype at 96 HAT. So, the S biotype translocated 40% of 14C-glyphosate absorbed to roots, and the R biotype translocated only 28% of herbicide at the same period. At low temperatures, there were no differences between biotypes, and at 96 HAT, the 14C-glyphosate found in treated leaves was ˜47% and up to ˜42% reached the roots, i.e., the resistance mechanism was suppressed. The basal and enzymatic activities of the 5-enolpyruvyishikimate 3-phosphate synthase were different between temperature regimes, but there was no differences between biotypes within each temperature regime, showing that target-site resistance mechanisms did not contribute in the glyphosate resistance of the R biotype. Low temperatures enhanced the absorption and translocation of glyphosate by suppressing the resistance mechanisms improving its efficacy on resistant plants. This is the first characterization about the role of temperatures in the glyphosate efficacy on C. sumatrensis.


Assuntos
Temperatura Baixa , Conyza/metabolismo , Glicina/análogos & derivados , Resistência a Herbicidas , Herbicidas/metabolismo , Absorção Fisiológica , Transporte Biológico , Radioisótopos de Carbono , Glicina/metabolismo
19.
Nat Commun ; 10(1): 3325, 2019 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-31346171

RESUMO

Serum resistance is a poorly understood but common trait of some difficult-to-treat pathogenic strains of bacteria. Here, we report that glycine, serine and threonine catabolic pathway is down-regulated in serum-resistant Escherichia coli, whereas exogenous glycine reverts the serum resistance and effectively potentiates serum to eliminate clinically-relevant bacterial pathogens in vitro and in vivo. We find that exogenous glycine increases the formation of membrane attack complex on bacterial membrane through two previously unrecognized regulations: 1) glycine negatively and positively regulates metabolic flux to purine biosynthesis and Krebs cycle, respectively. 2) α-Ketoglutarate inhibits adenosine triphosphate synthase, which in together promote the formation of cAMP/CRP regulon to increase the expression of complement-binding proteins HtrE, NfrA, and YhcD. The results could lead to effective strategies for managing the infection with serum-resistant bacteria, an especially valuable approach for treating individuals with weak acquired immunity but a normal complement system.


Assuntos
Proteínas do Sistema Complemento/imunologia , Infecções por Escherichia coli/imunologia , Escherichia coli/metabolismo , Glicina/metabolismo , Serina/metabolismo , Soro/química , Treonina/metabolismo , Trifosfato de Adenosina/metabolismo , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Chaperoninas/genética , Chaperoninas/metabolismo , Ciclo do Ácido Cítrico , Complexo de Ataque à Membrana do Sistema Complemento/genética , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Humanos , Purinas/biossíntese
20.
PLoS One ; 14(7): e0220050, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31348796

RESUMO

Bile acid reflux is known to be associated with the development of Barrett's esophagus and esophageal adenocarcinoma (EAC), yet the role of specific bile acids and the mechanism behind the metaplastic changes is unclear. Here, we demonstrate that multi-layered glandular structures at the squamo-columnar junction in mice contain multiple cell lineages, which resemble the human esophageal submucosal gland ducts. Exposing mice to patient's refluxates induced expansion of multi-layered glandular structures and development of columnar metaplasia at the squamo-columnar junction. The glycine conjugated bile acids induced an intestinal type of metaplasia more typical for Barrett's esophagus. Through lineage tracing, we excluded the involvement of K5+, DCLK1+, and LGR5+ progenitor cells as the primary source in the development of the glandular metaplastic epithelium. We show that the mechanism behind development of metaplasia involves crypt fission and may be independent of stem cell proliferation. Our findings support the hypothesis that in humans, BE arises from non-squamous cells residing in submucosal gland ducts and that induction of intestinal type of metaplasia is most effectively induced by glycine-conjugated bile acids. These novel insights may lead to more effective strategies to prevent development of Barrett's esophagus and esophageal adenocarcinoma.


Assuntos
Adenocarcinoma/metabolismo , Esôfago de Barrett/patologia , Ácidos e Sais Biliares/metabolismo , Neoplasias Esofágicas/metabolismo , Glicina/metabolismo , Animais , Esôfago de Barrett/metabolismo , Cromatografia Líquida de Alta Pressão , Modelos Animais de Doenças , Glicosilação , Humanos , Masculino , Metaplasia , Camundongos
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