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1.
Stud Health Technol Inform ; 273: 123-128, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-33087601

RESUMO

Type 2 diabetes is one of the most common chronic diseases in the world. World Diabetes Federation experts predict that the diabetes patients' number by 2035 will increase by 205 million to reach 592 million. For health care, this diabetes type is one of the highest priority problems. This disease is associated with many concomitant diseases leading to early disability and high cardiovascular risk. A severity disease indicator is the degree of carbohydrate metabolism compensation. Decompensated and subcompensated carbohydrate metabolism patients have increased cardiovascular risks. Therefore, it is important to be able to select the right therapy to control carbohydrate metabolism. In this study, we propose a new method for selecting the optimal therapy automatically. The method includes creating personal optimal therapies. This kind of therapy has the highest probability of compensating carbohydrate metabolism for a patient within a six-month. The method includes models for predicting the results of different therapies. It is based on data from the previous medical history and current medical indicators of patients. This method provides high-quality predictions and medical recommendations. Therefore, medical professionals can use this method as part of the Support and Decision-Making Systems for working with T2DM patients.


Assuntos
Diabetes Mellitus Tipo 2 , Metabolismo dos Carboidratos , Análise Fatorial , Humanos , Aprendizado de Máquina
2.
Nat Commun ; 11(1): 4874, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978395

RESUMO

Organic synthesis methodology enables the synthesis of complex molecules and materials used in all fields of science and technology and represents a vast body of accumulated knowledge optimally suited for deep learning. While most organic reactions involve distinct functional groups and can readily be learned by deep learning models and chemists alike, regio- and stereoselective transformations are more challenging because their outcome also depends on functional group surroundings. Here, we challenge the Molecular Transformer model to predict reactions on carbohydrates where regio- and stereoselectivity are notoriously difficult to predict. We show that transfer learning of the general patent reaction model with a small set of carbohydrate reactions produces a specialized model returning predictions for carbohydrate reactions with remarkable accuracy. We validate these predictions experimentally with the synthesis of a lipid-linked oligosaccharide involving regioselective protections and stereoselective glycosylations. The transfer learning approach should be applicable to any reaction class of interest.


Assuntos
Carboidratos/química , Aprendizado de Máquina , Oligossacarídeos/química , Metabolismo dos Carboidratos , Técnicas de Química Sintética , Glicosilação , Estrutura Molecular , Oligossacarídeos/metabolismo
3.
PLoS One ; 15(8): e0237885, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32853234

RESUMO

Our group has developed two transplantation models for the engraftment of Human Intestinal Organoids (HIOs): the renal subcapsular space (RSS) and the mesentery each with specific benefits for study. While engraftment at both sites generates laminated intestinal structures, a direct comparison between models has not yet been performed. Embryonic stem cells were differentiated into HIOs, as previously described. HIOs from the same batch were transplanted on the same day into either the RSS or mesentery. 10 weeks were allowed for engraftment and differentiation, at which time they were harvested and assessed. Metrics for comparison included: mortality, engraftment rate, gross size, number and grade of lumens, and expression of markers specific to epithelial differentiation, mesenchymal differentiation, and carbohydrate metabolism. Mortality was significantly increased when undergoing mesentery transplantation, however engraftment was significantly higher. Graft sizes were similar between groups. Morphometric parameters were similar between groups, however m-tHIOs presented with significantly fewer lumens than k-tHIO. Transcript and protein level expression of markers specific to epithelial differentiation, mesenchymal differentiation, and carbohydrate metabolism were similar between groups. Transplantation into both sites yields viable tissue of similar quality based on our assessments with enhanced engraftment and a dominant lumen for uniform study benefiting the mesenteric site and survival benefiting RSS.


Assuntos
Intestinos/transplante , Organoides/transplante , Animais , Metabolismo dos Carboidratos , Linhagem da Célula , Células Epiteliais/citologia , Sobrevivência de Enxerto , Humanos , Masculino , Camundongos Endogâmicos NOD , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
4.
Ecotoxicol Environ Saf ; 202: 111011, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800236

RESUMO

Boron (B) deficiency and surplus are the main factors that affect plant growth and yield. A better understanding of the response mechanisms of plant reproductive organs to stress induced by B deficiency and surplus could provide new insights to potential strategies for improving seed yield and quality. In this study, we aimed to elucidate the mechanisms of tolerance to B-induced stress in the reproductive organs of alfalfa (Medicago sativa L. cv. 'Aohan'). We initially used five B concentrations (0 mg B L-1, 400 mg B L-1, 800 mg B L-1, 1200 mg B L-1, and 1600 mg B L-1) to determine the B deficient, sufficient, and surplus levels in the field. Secondly, we examined changes in metabolite profiles of alfalfa 'Aohan' reproductive organs in response to B deficiency (0 mg B L-1), B sufficiency (800 mg B L-1), and B surplus (1600 mg B L-1) conditions using gas chromatography-mass spectrometry (GC-MS). Flowers and seeds from alfalfa 'Aohan' showed different metabolite profiles and resistance capacity under B deficiency and surplus conditions. B deficiency led to the excessive accumulation of sugars and phenolic compounds in alfalfa 'Aohan' and seeds, respectively, thus causing abscission or the abortion of reproductive organs. In contrast, B surplus severely reduced the levels of metabolites associated with amino acid and carbohydrate metabolism, resulting in the flowers falling and, therefore, low seed yield. Overall, B deficiency predominantly reduced seed yield and quality of alfalfa 'Aohan', while B surplus mainly affected seed yield of alfalfa 'Aohan'.


Assuntos
Boro/deficiência , Boro/toxicidade , Células Germinativas Vegetais/efeitos dos fármacos , Medicago sativa/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Poluentes do Solo/toxicidade , Aminoácidos/metabolismo , Metabolismo dos Carboidratos/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Células Germinativas Vegetais/metabolismo , Medicago sativa/metabolismo , Metabolômica , Sementes/metabolismo , Poluentes do Solo/metabolismo
5.
PLoS One ; 15(8): e0237194, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760135

RESUMO

We aimed to profile the metabolism of soybean roots that were infected with soybean cyst nematodes and treated with Bacillus simplex to identify metabolic differences that may explain nematode resistance. Compared with control soybean roots, B. simplex-treated soybean roots contained lower levels of glucose, fructose, sucrose, and trehalose, which reduced the nematodes' food source. Furthermore, treatment with B. simplex led to higher levels of melibiose, gluconic acid, lactic acid, phytosphingosine, and noradrenaline in soybean roots, which promoted nematocidal activity. The levels of oxoproline, maltose, and galactose were lowered after B. simplex treatment, which improved disease resistance. Collectively, this study provides insight into the metabolic alterations induced by B. simplex treatment, which affects the interactions with soybean cyst nematodes.


Assuntos
Bacillus/patogenicidade , Resistência à Doença , Metaboloma , Nematoides/patogenicidade , Soja/parasitologia , Animais , Metabolismo dos Carboidratos , Doenças das Plantas/microbiologia , Doenças das Plantas/parasitologia , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Raízes de Plantas/parasitologia , Soja/metabolismo , Soja/microbiologia
6.
PLoS One ; 15(8): e0237457, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32780764

RESUMO

Onion (Allium cepa L.) is an important vegetable crop widely grown for diverse culinary and nutraceutical properties. Being a shallow-rooted plant, it is prone to drought. In the present study, transcriptome sequencing of drought-tolerant (1656) and drought-sensitive (1627) onion genotypes was performed to elucidate the molecular basis of differential response to drought stress. A total of 123206 and 139252 transcripts (average transcript length: 690 bases) were generated after assembly for 1656 and 1627, respectively. Differential gene expression analyses revealed upregulation and downregulation of 1189 and 1180 genes, respectively, in 1656, whereas in 1627, upregulation and downregulation of 872 and 1292 genes, respectively, was observed. Genes encoding transcription factors, cytochrome P450, membrane transporters, and flavonoids, and those related to carbohydrate metabolism were found to exhibit a differential expression behavior in the tolerant and susceptible genotypes. The information generated can facilitate a better understanding of molecular mechanisms underlying drought response in onion.


Assuntos
Secas , Regulação da Expressão Gênica de Plantas , Cebolas/genética , Metabolismo dos Carboidratos/genética , Perfilação da Expressão Gênica/métodos , Genótipo , Proteínas de Membrana Transportadoras/genética , RNA de Plantas/química , RNA de Plantas/metabolismo , Fatores de Transcrição/genética
7.
Ecotoxicol Environ Saf ; 203: 110943, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32678750

RESUMO

High temperature damage impairs the growth of tall fescue by inhibiting secondary metabolites. Little is known about the regulation pattern of the fatty acids and carbohydrate metabolism at the whole-transcriptome level in tall fescue under high temperature stress. Here, two tall fescue genotypes, heat tolerant PI578718 and heat sensitive PI234881 were subjected to high temperature stress for 36 h. PI 578718 showed higher SPAD chloroplast value, lower EL and leaf injury than PI 234881 during the first 36 h high-temperature stress. Furthermore, by transcriptomic analysis, 121 genes were found to be induced during the second energy production phase in tall fescue exposed to high-temperature conditions, indicating that there may be one energy-sensing system in cool-season turfgrass to adapt high-temperature conditions. PI 578718 showed higher differentially expressed unigenes involved in fatty acids and carbohydrate metabolism compared with PI 234881 for 36 h heat stress. Interestingly, a metabolomic analysis using GC-MS uncovered that the sugars and sugar alcohol accounted for more than 65.06% of the total 41 metabolites content and high-temperature elevated the rate to 82.89-91.16% in PI 578718. High-temperature damage decreased the rate of fatty acid in the total 41 metabolites content and PI 578718 showed lower content than in PI 234881, which might be attributed to the down-regulated genes in fatty acid biosynthesis pathway in tall fescue. The integration of deep transcriptome and metabolome analyses provides systems-wide datasets to facilitate the identification of crucial regulation factors in cool-season turfgrass in response to high-temperature damage.


Assuntos
Metabolismo dos Carboidratos/efeitos dos fármacos , Ácidos Graxos/metabolismo , Festuca , Resposta ao Choque Térmico , Temperatura Alta , Metabolismo dos Carboidratos/genética , Ácidos Graxos/genética , Festuca/genética , Festuca/crescimento & desenvolvimento , Festuca/metabolismo , Perfilação da Expressão Gênica , Resposta ao Choque Térmico/genética , Metabolômica , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo
9.
Eur J Endocrinol ; 183(4): 439-452, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32698159

RESUMO

Objective: Combining conjugated estrogens (CE) with the selective estrogen receptor modulator bazedoxifene (BZA) is a novel, orally administered menopausal therapy. We investigated the effect of CE/BZA on insulin sensitivity, energy metabolism, and serum metabolome in postmenopausal women with obesity. Design: Randomized, double-blind, crossover pilot trial with washout was conducted at Pennington Biomedical Research Center. Eight postmenopausal women (age 50-60 years, BMI 30-40 kg/m2) were randomized to 8 weeks CE/BZA or placebo. Primary outcome was insulin sensitivity (hyperinsulinemic-euglycemic clamp). Secondary outcomes included body composition (DXA); resting metabolic rate (RMR); substrate oxidation (indirect calorimetry); ectopic lipids (1H-MRS); fat cell size, adipose and skeletal muscle gene expression (biopsies); serum inflammatory markers; and serum metabolome (LC/MS). Results: CE/BZA treatment produced no detectable effect on insulin sensitivity, body composition, ectopic fat, fat cell size, or substrate oxidation, but resulted in a non-significant increase in RMR (basal: P = 0.06; high-dose clamp: P = 0.08) compared to placebo. CE/BZA increased serum high-density lipoprotein (HDL)-cholesterol. CE/BZA also increased serum diacylglycerol (DAG) and triacylglycerol (TAG) species containing long-chain saturated, mono- and polyunsaturated fatty acids (FAs) and decreased long-chain acylcarnitines, possibly reflecting increased hepatic de novo FA synthesis and esterification into TAGs for export into very low-density lipoproteins, as well as decreased FA oxidation, respectively (P < 0.05). CE/BZA increased serum phosphatidylcholines, phosphatidylethanolamines, ceramides, and sphingomyelins, possibly reflecting the increase in serum lipoproteins (P < 0.05). Conclusions: A short treatment of obese postmenopausal women with CE/BZA does not alter insulin action or ectopic fat but increases serum markers of hepatic de novo lipogenesis and TAG production.


Assuntos
Metabolismo dos Carboidratos/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Estrogênios Conjugados (USP)/farmacologia , Glucose/metabolismo , Indóis/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Obesidade/metabolismo , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Estudos Cross-Over , Método Duplo-Cego , Estrogênios Conjugados (USP)/uso terapêutico , Feminino , Humanos , Indóis/uso terapêutico , Pessoa de Meia-Idade , Obesidade/tratamento farmacológico , Projetos Piloto , Pós-Menopausa/efeitos dos fármacos , Pós-Menopausa/metabolismo
10.
PLoS One ; 15(7): e0236424, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32730292

RESUMO

Grapevines, although adapted to occasional drought or salt stress, are relatively sensitive to growth- and yield-limiting salinity stress. To understand the molecular mechanisms of salt tolerance and endoplasmic reticulum (ER) stress and identify genes commonly regulated by both stresses in grapevine, we investigated transcript profiles in leaves of the salt-tolerant grapevine rootstock 1616C under salt- and ER-stress. Among 1643 differentially expressed transcripts at 6 h post-treatment in leaves, 29 were unique to ER stress, 378 were unique to salt stress, and 16 were common to both stresses. At 24 h post-treatment, 243 transcripts were unique to ER stress, 1150 were unique to salt stress, and 168 were common to both stresses. GO term analysis identified genes in categories including 'oxidative stress', 'protein folding', 'transmembrane transport', 'protein phosphorylation', 'lipid transport', 'proteolysis', 'photosynthesis', and 'regulation of transcription'. The expression of genes encoding transporters, transcription factors, and proteins involved in hormone biosynthesis increased in response to both ER and salt stresses. KEGG pathway analysis of differentially expressed genes for both ER and salt stress were divided into four main categories including; carbohydrate metabolism, amino acid metabolism, signal transduction and lipid metabolism. Differential expression of several genes was confirmed by qRT-PCR analysis, which validated our microarray results. We identified transcripts for genes that might be involved in salt tolerance and also many genes differentially expressed under both ER and salt stresses. Our results could provide new insights into the mechanisms of salt tolerance and ER stress in plants and should be useful for genetic improvement of salt tolerance in grapevine.


Assuntos
Estresse do Retículo Endoplasmático/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Raízes de Plantas/genética , Estresse Salino/genética , Vitis/genética , Metabolismo dos Carboidratos/genética , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ontologia Genética , Análise de Sequência com Séries de Oligonucleotídeos , Osmose , Reguladores de Crescimento de Planta/farmacologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Caules de Planta/efeitos dos fármacos , Caules de Planta/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Estresse Salino/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Fatores de Transcrição/metabolismo , Tunicamicina/farmacologia
11.
Bull Environ Contam Toxicol ; 105(3): 411-421, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32725326

RESUMO

Phytoremediation is an ecologically and economically feasible technique to remove heavy metal from soil. The aim of the study was to examine cadmium (Cd) toxicity and phytoremediation aptitude of Brassica juncea. In the present study, plants survived when exposed to different levels of Cd (0, 25, 50 and 100 mg/kg soil) and accumulated a large amount of Cd in its root and shoot. Translocation factor (TF) of Cd from root to shoot was > 1 at both 45 and 60-day stage of growth suggesting that B. juncea is a hyperaccumulator and strong candidate for phytoextraction of Cd. Alongside, Cd impaired photolysis of water, PSII activity, nutrient uptake, photosynthesis and sugar accumulation in the plant. Cd-generated oxidative stress restricts the growth of B. juncea. The toxic effect of Cd was more pronounced at 45-day stage of growth signifying the drifting of plant towards acquirement of exclusion strategy.


Assuntos
Biodegradação Ambiental , Cádmio/metabolismo , Mostardeira/metabolismo , Poluentes do Solo/metabolismo , Cádmio/análise , Metabolismo dos Carboidratos , Gases , Metais Pesados/metabolismo , Mostardeira/efeitos dos fármacos , Mostardeira/crescimento & desenvolvimento , Oxirredução , Solo , Poluentes do Solo/análise
12.
Ecotoxicol Environ Saf ; 201: 110869, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32585490

RESUMO

Chromium (Cr) contamination is a potential threat to the agricultural soil. Arbuscular mycorrhizal (AM) fungi have potential to remediate the heavy metal polluted soils. It was hypothesized that Cr phytoremediation potentiality of AM fungi could be enhanced in combination with saprophytic filamentous fungi and soil amendment. Tomato plants were raised in Cr polluted technosol amended with compost, inoculated with mixed-culture of AM fungi and Aspergillus terreus. It was found that, triple treatment (soil amendment with compost along with AM fungi and A. terreus inoculation) enhanced biomass production (up to 315%), fruit setting (up to 49%), photosynthetic pigments (up to 214%) and carbohydrate content (up to 400%) whereas reduced the proline (up to 76.5%), catalase (up to 34.2%), peroxidase (up to 58.9%) and root membrane permeability (up to 74.2%). The effect of AM fungi with compost amendment was additive, while it was synergistic with A. terreus. AM fungi enhanced the extraction of Cr from the substrate, but retained in the mycorrhizal root, thereby reduced the translocation into shoot and in fruit, Cr translocation was undetectable. At the end of experiment Cr content in the substrate was significantly decreased (up to 37.9%). Soil amendment with compost along with AM fungi and A. terreus inoculation can be used for reclamation of Cr polluted soils at field scale.


Assuntos
Aspergillus/fisiologia , Cromo/farmacocinética , Lycopersicon esculentum/metabolismo , Micorrizas/fisiologia , Poluentes do Solo/farmacocinética , Biodegradação Ambiental , Biomassa , Metabolismo dos Carboidratos , Catalase/metabolismo , Compostagem , Lycopersicon esculentum/enzimologia , Peroxidase/metabolismo , Raízes de Plantas/metabolismo , Prolina/metabolismo
13.
Ecotoxicol Environ Saf ; 201: 110822, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32534334

RESUMO

Boron (B) toxicity is an important abiotic constraint that limits crop productivity mainly in arid and semi-arid areas of the world. High levels of B in soil disturbs several physiological and biochemical processes in plant. The aim of this study was to investigate the function of melatonin (Mel) in the regulation of carbohydrate and proline (Pro) metabolism, photosynthesis process and antioxidant system of wheat seedlings under B toxicity conditions. High levels of B inhibited net photosynthetic rate (PN), stomatal conductance (gs), content of chlorophyll (Chl) a, b, δ-aminolevulinic acid (δ-ALA), nitrogen (N) and phosphorus (P), and increased accumulation of B, Chl degradation and activity of chlorophyllase (Chlase; a Chl degrading enzyme), and downregulated the activity of enzymes (δ-ALAD; δ-aminolevulinic acid dehydratase) involved in the biosynthesis of photosynthesis pigments, photosynthesis (carbonic anhydrase and ribulose-1,5-bisphosphate carboxylase/oxygenase) and carbohydrate metabolism (cell wall invertase, CWI) in wheat seedlings. Also, high levels of B caused oxidative damage by increasing the content of malondialdehyde, superoxide anion and H2O2, and activity of glycolate oxidase (an H2O2-producing enzyme) in leaves of seedlings. However, foliar application of Mel significantly improved photosynthetic pigments concentration by increasing δ-ALA, δ-ALAD and decreasing Chl degradation and Chlase activity and led to an increase of plant growth attributes under both B toxicity and non-toxicity conditions. Under normal and B toxicity conditions, exogenous Mel also improved content of N, P, total soluble carbohydrates (TSCs) and Pro, and upregulated activity of CWI and Δ1-pyrroline-5-carboxylate synthetase. Mel significantly suppressed the adverse effects of excess B by alleviating cellular oxidative damage through enhanced reactive oxygen species scavenging by superoxide dismutase, catalase, ascorbate peroxidase, glutathione reductase and lipoxygenase, and content of total phenolic compounds (TPC), ascorbate and reduced glutathione. These results postulate that Mel induced plant defense mechanisms by enhancing Pro, TSCs, TPC, nutrients (N and P) uptake and enzymatic and non-enzymatic antioxidants.


Assuntos
Antioxidantes/metabolismo , Boro/toxicidade , Melatonina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Poluentes do Solo/toxicidade , Triticum/efeitos dos fármacos , Metabolismo dos Carboidratos/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
14.
Nat Commun ; 11(1): 3120, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32561727

RESUMO

Hyaluronan is widely used in cosmetics and pharmaceutics. Development of robust and safe cell factories and cultivation approaches to efficiently produce hyaluronan is of many interests. Here, we describe the metabolic engineering of Corynebacterium glutamicum and application of a fermentation strategy to manufacture hyaluronan with different molecular weights. C. glutamicum is engineered by combinatorial overexpression of type I hyaluronan synthase, enzymes of intermediate metabolic pathways and attenuation of extracellular polysaccharide biosynthesis. The engineered strain produces 34.2 g L-1 hyaluronan in fed-batch cultures. We find secreted hyaluronan encapsulates C. glutamicum, changes its cell morphology and inhibits metabolism. Disruption of the encapsulation with leech hyaluronidase restores metabolism and leads to hyper hyaluronan productions of 74.1 g L-1. Meanwhile, the molecular weight of hyaluronan is also highly tunable. These results demonstrate combinatorial optimization of cell factories and the extracellular environment is efficacious and likely applicable for the production of other biopolymers.


Assuntos
Corynebacterium glutamicum/enzimologia , Glucose/metabolismo , Ácido Hialurônico/biossíntese , Engenharia Metabólica/métodos , Cápsulas Bacterianas/genética , Cápsulas Bacterianas/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Técnicas de Cultura Celular por Lotes/métodos , Metabolismo dos Carboidratos/genética , Corynebacterium glutamicum/genética , Meios de Cultura/metabolismo , Hialuronan Sintases/genética , Hialuronan Sintases/metabolismo , Hialuronoglucosaminidase/metabolismo , Redes e Vias Metabólicas/genética , Polissacarídeos Bacterianos/biossíntese
15.
Ying Yong Sheng Tai Xue Bao ; 31(4): 1378-1388, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32530214

RESUMO

Non-structural carbohydrates (NSC) are essential substances for the tree growth and metabolism, and play an important role in environmental adaptation of trees. At temporal scale, NSC contents in trees have limited inter-annual variation, which could be attributed to the strategy of tree growth and carbon storage. Different factors influence NSC contents of trees in various climatic regions, which change substantially at the seasonal scale. At spatial scale, the variations of NSC content in trees show an insignificantly decreasing trend with the decreases of latitude at global and continental scales, which are mainly related to the hydrothermal gradients. The trend at regional scale is opposite because of the decrease of hydrothermal gradients and lower sample frequency. More sophisticated relations exist between the variations of NSC content in trees and altitudes, which are caused by species-specific characteristics and the variations of micro-habitat conditions. The variations of NSC content in trees at multiple spatial-temporal scales are generally determined by both biotic and abiotic factors, which are mainly dependent on the tradeoff among photosynthate production, respiratory depletion, and tree growth. Furthermore, the methods used for the determination of NSC content are different, which results in great uncertainties in comparing conclusions from different studies. The methods used for sample collection and measurement of NSC should be improved and unified to enhance the comparison among different studies. The NSC contents of trees in different age classes should be measured with all organs collected at multiple spatial-temporal scales. The underlying mechanisms, significance of NSC storage, transformation and allocation on tree growth and survival should be further discussed.


Assuntos
Metabolismo dos Carboidratos , Árvores , Carboidratos , Carbono , Estações do Ano
16.
Artigo em Inglês | MEDLINE | ID: mdl-32594380

RESUMO

Influence of arsenic (As) in As tolerant and sensitive rice genotypes based chloroplastic pigments, leaf gas exchange attributes and their influence on carbohydrate metabolism were investigated in the present study. As retards growth of crop plants and increase several health ailments by contaminating food chain. Photosynthetic inhibition is known to be the prime target of As toxicity due to over-production of ROS. Hydroponically grown rice seedlings of twelve cultivars were exposed to 25, 50, and 75 µM arsenate (AsV) that exerted negative impact on plastidial pigments content and resulted into inhibition of Hill activity. Internal CO2 concentration lowered gradually due to interference of As with stomatal conductance and transpiration rate that subsequently led to drop in net photosynthesis. Twelve contrasting rice genotypes responded differentially to As(V) stress. Present study evaluated As tolerant and sensitive rice cultivars with respect to As(V) imposed alterations in pigments content, photosynthetic attributes along with sugar metabolism. Starch contents, the principle carbohydrate storage declined differentially among As(V) stressed test cultivars, being more pronounced in cvs. Swarnadhan, Tulaipanji, Pusa basmati, Badshabhog, Tulsibhog and IR-20 compared to cvs. Bhutmuri, Kumargore, Binni, Vijaya, TN-1 and IR-64. Therefore, the six former cultivars tried to adapt defensive mechanisms by accumulating higher levels of reducing and non-reducing sugars to carry out basal metabolism to withstand As(V) induced alterations in photosynthesis. This study could help to screen As tolerant and sensitive rice genotypes based on their photosynthetic efficiency in As polluted agricultural fields to reduce As contamination assisted ecotoxicological risk.


Assuntos
Arseniatos/efeitos adversos , Metabolismo dos Carboidratos/efeitos dos fármacos , Oryza/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Poluentes do Solo/efeitos adversos , Genótipo , Oryza/genética , Oryza/fisiologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Estresse Fisiológico
17.
Nature ; 582(7813): 592-596, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32555458

RESUMO

Proteins carry out the vast majority of functions in all biological domains, but for technological reasons their large-scale investigation has lagged behind the study of genomes. Since the first essentially complete eukaryotic proteome was reported1, advances in mass-spectrometry-based proteomics2 have enabled increasingly comprehensive identification and quantification of the human proteome3-6. However, there have been few comparisons across species7,8, in stark contrast with genomics initiatives9. Here we use an advanced proteomics workflow-in which the peptide separation step is performed by a microstructured and extremely reproducible chromatographic system-for the in-depth study of 100 taxonomically diverse organisms. With two million peptide and 340,000 stringent protein identifications obtained in a standardized manner, we double the number of proteins with solid experimental evidence known to the scientific community. The data also provide a large-scale case study for sequence-based machine learning, as we demonstrate by experimentally confirming the predicted properties of peptides from Bacteroides uniformis. Our results offer a comparative view of the functional organization of organisms across the entire evolutionary range. A remarkably high fraction of the total proteome mass in all kingdoms is dedicated to protein homeostasis and folding, highlighting the biological challenge of maintaining protein structure in all branches of life. Likewise, a universally high fraction is involved in supplying energy resources, although these pathways range from photosynthesis through iron sulfur metabolism to carbohydrate metabolism. Generally, however, proteins and proteomes are remarkably diverse between organisms, and they can readily be explored and functionally compared at www.proteomesoflife.org.


Assuntos
Classificação , Aprendizado Profundo , Peptídeos/química , Peptídeos/isolamento & purificação , Proteoma/química , Proteoma/isolamento & purificação , Proteômica/métodos , Animais , Bacteroides/química , Bacteroides/classificação , Metabolismo dos Carboidratos , Cromatografia , Glicólise , Homeostase , Transporte de Íons , Proteínas com Ferro-Enxofre/metabolismo , Oxirredução , Fotossíntese , Biossíntese de Proteínas , Dobramento de Proteína , Proteólise , Especificidade da Espécie
18.
Chemosphere ; 253: 126772, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32464760

RESUMO

Zeranol is an approved but controversial growth-promoting agent for livestock in North America. It is a mycotoxin metabolite secreted by the Fusarium family fungi. The regulatory bodies in this region have established the acceptable daily intake and exposure below the level would not significantly increase the health risk for humans. However, their European counterparts have yet to establish an acceptable level and do not permit the use of this agent in farm animals. Given the growth-promoting ability of zeranol, its effect on energy metabolism was investigated in the current study. Our results indicated that zeranol could induce glucose transporter type 4 (GLUT4) expression in 3T3 L1 cells at 10 µM and initiate the translocation of the glucose transporter to the membrane as assayed by confocal microscopy. The translocation was likely triggered by the increase of GLUT4 and p-Akt. The insulin signal transduction pathway of glucose translocation was analyzed by Western blot analysis. Since no increase in the phosphorylated insulin receptor substrate in zeranol-treated cells was evidenced, the increased p-Akt and GLUT4 amount should be the mechanism dictating the GLUT4 translocation. In summary, this study showed that zeranol could perturb glucose metabolism in differentiated 3T3 L1 adipocytes. Determining the growth-promoting mechanism is crucial to uncover an accepted alternative to the general public.


Assuntos
Transportador de Glucose Tipo 4/metabolismo , Reguladores de Crescimento de Planta/toxicidade , Zeranol/toxicidade , Células 3T3-L1 , Adipócitos , Animais , Antígenos CD , Metabolismo dos Carboidratos , Glucose/metabolismo , Insulina/metabolismo , Gado , Camundongos , América do Norte , Fosforilação , Receptor de Insulina/metabolismo , Transdução de Sinais/efeitos dos fármacos
19.
PLoS Genet ; 16(5): e1008586, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32463816

RESUMO

The strength of bone depends on bone quantity and quality. Osteocalcin (Ocn) is the most abundant noncollagenous protein in bone and is produced by osteoblasts. It has been previously claimed that Ocn inhibits bone formation and also functions as a hormone to regulate insulin secretion in the pancreas, testosterone synthesis in the testes, and muscle mass. We generated Ocn-deficient (Ocn-/-) mice by deleting Bglap and Bglap2. Analysis of Ocn-/-mice revealed that Ocn is not involved in the regulation of bone quantity, glucose metabolism, testosterone synthesis, or muscle mass. The orientation degree of collagen fibrils and size of biological apatite (BAp) crystallites in the c-axis were normal in the Ocn-/-bone. However, the crystallographic orientation of the BAp c-axis, which is normally parallel to collagen fibrils, was severely disrupted, resulting in reduced bone strength. These results demonstrate that Ocn is required for bone quality and strength by adjusting the alignment of BAp crystallites parallel to collagen fibrils; but it does not function as a hormone.


Assuntos
Apatitas/metabolismo , Calcificação Fisiológica/genética , Metabolismo dos Carboidratos/genética , Glucose/metabolismo , Músculo Esquelético/crescimento & desenvolvimento , Osteocalcina/fisiologia , Testosterona/biossíntese , Animais , Apatitas/química , Osso e Ossos/metabolismo , Colágeno/metabolismo , Cristalização , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Desenvolvimento Muscular/genética , Músculo Esquelético/metabolismo , Tamanho do Órgão/genética , Osteoblastos/metabolismo , Osteocalcina/genética , Osteogênese/genética , Testículo/crescimento & desenvolvimento , Testículo/metabolismo
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