Sugars In Response Research Articles

Sulfadiazine degradation by Bjerkandera adusta DH0817 at low temperatures and its cold-adaptation mechanisms

The prolonged period of low temperatures in northern China poses a significant challenge to the bioremediation of antibiotic pollution. This study reports that a white-rot fungus Bjerkandera adusta DH0817, isolated from a poultry farm in Liaoning Province, can remove 60 % of SDZ within 20 days at 10°C and reduce the biotoxicity of SDZ. Six degradation pathways were proposed. SDZ biodegradation was primarily driven by cytochrome P450. Transcriptome analysis revealed that DH0817 upregulated genes associated with cell membrane, transcription factors and soluble sugars in response to low temperatures. Subsequently, genes associated with fatty acid, proteins and enzymes were upregulated to remove SDZ at low temperatures. This study provides valuable microbial resources and serves as a theoretical reference for addressing antibiotic pollution in livestock and poultry farms under low temperature conditions.

Upregulated hepatic lipogenesis from dietary sugars in response to low palmitate feeding supplies brain palmitate

Palmitic acid (PAM) can be provided in the diet or synthesized via de novo lipogenesis (DNL), primarily, from glucose. Preclinical work on the origin of brain PAM during development is scarce and contrasts results in adults. In this work, we use naturally occurring carbon isotope ratios (13C/12C; δ13C) to uncover the origin of brain PAM at postnatal days 0, 10, 21 and 35, and RNA sequencing to identify the pathways involved in maintaining brain PAM, at day 35, in mice fed diets with low, medium, and high PAM from birth. Here we show that DNL from dietary sugars maintains the majority of brain PAM during development and is augmented in mice fed low PAM. Importantly, the upregulation of hepatic DNL genes, in response to low PAM at day 35, demonstrates the presence of a compensatory mechanism to maintain total brain PAM pools compared to the liver; suggesting the importance of brain PAM regulation.

Vacuolar Phosphate Transporter1 (VPT1) may transport sugar in response to soluble sugar status of grape fruits.

Vacuolar Phosphate Transporter1 (VPT1)-mediated phosphate uptake in the vacuoles is essential to plant development and fruit ripening. Interestingly, here we find that the VPT1 may transport sugar in response to soluble sugar status of fruits. The VvVPT1 protein isolated from grape (Vitis vinifera) berries was tonoplast-localized and contains SPX (Syg1/Pho81/XPR1) and MFS (major facilitator superfamily) domains. Its mRNA expression was significantly increased during fruit ripening and induced by sucrose. Functional analyses based on transient transgenic systems in grape berry showed that VvVPT1 positively regulated berry ripening and significantly affected hexose contents, fruit firmness, and ripening-related gene expression. The VPT1 proteins (Grape VvVPT1, strawberry FaVPT1, and Arabidopsis AtVPT1) all showed low affinity for phosphate verified in yeast system, while they appear different in sugar transport capacity, consistent with fruit sugar status. Thus, our findings reveal a role for VPT1 in fruit ripening, associated to its SPX and MFS domains in direct transport of soluble sugar available into the vacuole, and open potential avenues for genetic improvement in fleshy fruit.

ФИЗИОЛОГО-БИОХИМИЧЕСКОЕ ИЗУЧЕНИЕ ЗИМОСТОЙКОСТИ ВИНОГРАДА

In the unstable conditions of the Anapo-Taman zone of the Krasnodar Kray, the issues of grape resistance to low tempera-tures in the winter period are of particular relevance. The results of a physiological and biochemical assessment of the winter hardiness of grape varieties (interspecific hybrids) of various ecological and geo-graphical origin are presented: Kristall (control – Euro-Amur-American origin; Dostoyny, Krasnostop AZOS – Euro-American origin; Vostorg – Amur-American origin; Aligote – Western-European origin, Zarif – East European origin. The studies were carried out on the basis of the ampelographic collection of the "North Caucasian Federal Scientific Center for Horticulture, Viticulture, Winemaking" (NCFSCHVW), located in the city of Anapa. Differences in the water content of the buds, the content starch, soluble sugars, proline, associated with the formation of a protective response to the meteorological conditions of the autumn-winter period 2020–2022. According to the degree of decrease in water content of the buds, the degree of starch hydrolysis, the dynamics of the accumulation of water soluble sugars in response to low temperatures in the win-ter period varieties Kristall, Krasnostop AZOS, Vostorg showed the greatest po-tential for resistance to low temperatures in the autumn-winter period of 2020–2022 compared to other varieties studied. Varie-ties Kristall, Krasnostop AZOS, Vostorg are recommended for cultivation in the Anapo-Taman zone of the Krasnodar Kray and for breeding purposes as sources of winter hardiness.

Effects of a plant-derived biostimulant application on quality and functional traits of greenhouse cherry tomato cultivars

A greenhouse experiment was conducted to study the effects of the application of a plant-derived biostimulant (Bioup® TF) on fruit quality and composition of two clusters (cluster II and cluster VI) of the cherry tomato cultivars ‘Eletta’, ‘Kaucana’, and ‘Top Stellina’. The biostimulant application promoted fruit yield by 12% (up to 1.3 kg m−2 in ‘Kaucana’) and increased the concentrations of important functional constituents like phytoene, γ-tocopherol and β-tocopherol by up to 16, 25, and 23%, respectively. Fruits from late-ripe cluster VI showed higher fruit weights, D-fructose, and total sugar contents than those from early-ripe cluster II (by 15, 7 and 5%, respectively), but reduced concentrations of acyclic carotenoids (phytoene and lycopene) and tocochromanols (mainly γ-tocopherol, −44%). ‘Top Stellina’ showed the highest responsiveness to the biostimulant, as particularly (all-E)-β-carotene, phytofluene, and γ-tocopherol concentrations increased, indicating a genotype-dependent effect of the treatment. However, fruits of all treated genotypes showed a contextual decrease in D-fructose and total sugars in response to the biostimulant (on average by 7 and 10%, respectively), indicating a metabolic load burdening the accumulation of lipophilic antioxidants in cherry tomatoes at the expense of their taste-related C pool.

Negative affect, childhood adversity, and adolescents' eating following stress

Obesity commonly emerges by adolescence and is associated with serious health consequences. Emotional eating (consuming calories, fats, and sugars in response to negative affect) may promote obesity; however, evidence is mixed as to whether negative affect increases obesogenic eating. Early-life adversity may shape malleable neurobiological systems that govern inhibitory control, physiological regulation, coping strategies, and eating behavior, contributing to greater obesogenic eating in response to negative affect. Therefore, this study tested whether childhood adversity moderates the association between negative affect and food consumption in a diverse sample of female adolescents. After completing a childhood adversity assessment, 157 female adolescents (13–17 years; 28.7% African American, 39.5% Hispanic/Latina, 31.8% Non-Hispanic White) rated their negative affect in response to a standard social stress paradigm before consuming a buffet lunch, which was evaluated for calories, added sugars, and solid fats consumed. Results did not support that negative affect exerted a main effect on eating behavior. However, negative affect and childhood adversity interacted to predict calories and solid fats consumed, such that negative affect was associated with more obesogenic eating for those with high adversity exposure but not for those with low adversity exposure. Adversity and affect did not interact to predict added sugars consumed. Findings support that eating patterns in response to negative affect may differ by childhood adversity history. Reducing children's adversity exposure and bolstering emotion regulation techniques for adolescents who have been exposed to adversity may provide pathways to protect health and well-being by reducing maladaptive eating patterns.

Exercise training modulates the gut microbiota profile and impairs inflammatory signaling pathways in obese children

Childhood obesity has reached epidemic levels and is a serious health concern associated with metabolic syndrome, nonalcoholic fatty liver disease, and gut microbiota alterations. Physical exercise is known to counteract obesity progression and modulate the gut microbiota composition. This study aims to determine the effect of a 12-week strength and endurance combined training program on gut microbiota and inflammation in obese pediatric patients. Thirty-nine obese children were assigned randomly to the control or training group. Anthropometric and biochemical parameters, muscular strength, and inflammatory signaling pathways in mononuclear cells were evaluated. Bacterial composition and functionality were determined by massive sequencing and metabolomic analysis. Exercise reduced plasma glucose levels and increased dynamic strength in the upper and lower extremities compared with the obese control group. Metagenomic analysis revealed a bacterial composition associated with obesity, showing changes at the phylum, class, and genus levels. Exercise counteracted this profile, significantly reducing the Proteobacteria phylum and Gammaproteobacteria class. Moreover, physical activity tended to increase some genera, such as Blautia, Dialister, and Roseburia, leading to a microbiota profile similar to that of healthy children. Metabolomic analysis revealed changes in short-chain fatty acids, branched-chain amino acids, and several sugars in response to exercise, in correlation with a specific microbiota profile. Finally, the training protocol significantly inhibited the activation of the obesity-associated NLRP3 signaling pathway. Our data suggest the existence of an obesity-related deleterious microbiota profile that is positively modified by physical activity intervention. Exercise training could be considered an efficient nonpharmacological therapy, reducing inflammatory signaling pathways induced by obesity in children via microbiota modulation.

The Apple Autophagy-Related Gene MdATG9 Confers Tolerance to Low Nitrogen in Transgenic Apple Callus.

Autophagy is an efficient degradation system for maintaining cellular homeostasis when plants are under environmental stress. ATG9 is the only integral membrane protein within the core ATG machinery that provides a membrane source for autophagosome formation. In this study, we isolated an ATG9 homologs gene in apple, MdATG9, from Malus domestica. The analysis of its sequence, subcellular localization, promoter cis-elements, and expression patterns revealed the potential function of MdATG9 in response to abiotic stressors. Overexpression of MdATG9 in apple callus conferred enhanced tolerance to nitrogen depletion stress. During the treatment, other important MdATGs were expressed at higher levels in transgenic callus than in the wild type. Furthermore, more free amino acids and increased sucrose levels were found in MdATG9-overexpression apple callus compared with the wild type in response to nitrogen starvation, and the expression levels of MdNRT1.1, MdNRT2.5, MdNIA1, and MdNIA2 were all increased higher in transgenic lines. These data suggest that, as an important autophagy gene, MdATG9 plays an important role in the maintenance of amino acids and sugars in response to nutrient starvation in apple.

Afectaciones fisiológicas y bioquímicas en vitroplantas de caña de azúcar en respuesta al estrés hídrico y salino

La producción agrícola es afectada negativamente por estrés biótico y abiótico, siendo responsables de grandes pérdidas económicas en el mundo. La caña de azúcar es la materia prima para obtener jugo de caña que se transforma en sacarosa y en la producción de etanol de segunda generación. En el presente estudio se evaluó el número de brotes y hojas, la concentración de prolina, clorofila a, b y total y la concentración de azúcares como respuesta al estrés hídrico y salino en dos variedades de caña de azúcar in vitro. Brotes individualizados de 5 cm de longitud de las variedades MotzMex 91-207 y SP 71-6180 de caña de azúcar se cultivaron in vitro bajo estrés hídrico (PEG 6000) y salino (NaCl). Las dos variedades de caña de azúcar analizadas in vitro presentaron respuestas diferentes al estrés osmótico. La variedad MotzMex 91-207 fue mejor que la variedad SP 71-6180 para responder al estrés hídrico con una mayor acumulación de prolina (82.34 mg g-1 PS), no presentó disminución en el contenido de clorofilas a, b y total y generó 20.8 brotes por explante aun en condiciones de estrés. Por otro lado, la respuesta al estrés salino con 50 mM NaCl in vitro la presentó la variedad SP 71-6180 al generar una mayor acumulación de carbohidratos como galactosa, glucosa y manosa.

Inhibition of microbial biofuel production in drought-stressed switchgrass hydrolysate.

BackgroundInterannual variability in precipitation, particularly drought, can affect lignocellulosic crop biomass yields and composition, and is expected to increase biofuel yield variability. However, the effect of precipitation on downstream fermentation processes has never been directly characterized. In order to investigate the impact of interannual climate variability on biofuel production, corn stover and switchgrass were collected during 3 years with significantly different precipitation profiles, representing a major drought year (2012) and 2 years with average precipitation for the entire season (2010 and 2013). All feedstocks were AFEX (ammonia fiber expansion)-pretreated, enzymatically hydrolyzed, and the hydrolysates separately fermented using xylose-utilizing strains of Saccharomyces cerevisiae and Zymomonas mobilis. A chemical genomics approach was also used to evaluate the growth of yeast mutants in the hydrolysates.ResultsWhile most corn stover and switchgrass hydrolysates were readily fermented, growth of S. cerevisiae was completely inhibited in hydrolysate generated from drought-stressed switchgrass. Based on chemical genomics analysis, yeast strains deficient in genes related to protein trafficking within the cell were significantly more resistant to the drought-year switchgrass hydrolysate. Detailed biomass and hydrolysate characterization revealed that switchgrass accumulated greater concentrations of soluble sugars in response to the drought and these sugars were subsequently degraded to pyrazines and imidazoles during ammonia-based pretreatment. When added ex situ to normal switchgrass hydrolysate, imidazoles and pyrazines caused anaerobic growth inhibition of S. cerevisiae.ConclusionsIn response to the osmotic pressures experienced during drought stress, plants accumulate soluble sugars that are susceptible to degradation during chemical pretreatments. For ammonia-based pretreatment, these sugars degrade to imidazoles and pyrazines. These compounds contribute to S. cerevisiae growth inhibition in drought-year switchgrass hydrolysate. This work discovered that variation in environmental conditions during the growth of bioenergy crops could have significant detrimental effects on fermentation organisms during biofuel production. These findings are relevant to regions where climate change is predicted to cause an increased incidence of drought and to marginal lands with poor water-holding capacity, where fluctuations in soil moisture may trigger frequent drought stress response in lignocellulosic feedstocks.Electronic supplementary materialThe online version of this article (doi:10.1186/s13068-016-0657-0) contains supplementary material, which is available to authorized users.

O-GlcNAcylation of G6PD promotes the pentose phosphate pathway and tumor growth.

The pentose phosphate pathway (PPP) plays a critical role in macromolecule biosynthesis and maintaining cellular redox homoeostasis in rapidly proliferating cells. Upregulation of the PPP has been shown in several types of cancer. However, how the PPP is regulated to confer a selective growth advantage on cancer cells is not well understood. Here we show that glucose-6-phosphate dehydrogenase (G6PD), the rate-limiting enzyme of the PPP, is dynamically modified with an O-linked β-N-acetylglucosamine sugar in response to hypoxia. Glycosylation activates G6PD activity and increases glucose flux through the PPP, thereby providing precursors for nucleotide and lipid biosynthesis, and reducing equivalents for antioxidant defense. Blocking glycosylation of G6PD reduces cancer cell proliferation in vitro and impairs tumor growth in vivo. Importantly, G6PD glycosylation is increased in human lung cancers. Our findings reveal a mechanistic understanding of how O-glycosylation directly regulates the PPP to confer a selective growth advantage to tumours.

English

Heavy metals are essential and important for plants growth, and play as key components of many vital compounds. However, when they increase in concentration, heavy metals show symptoms such as growth delay and inhibition of biochemical reactions. The current study focused on the impact of five heavy metals (lead, chromium, nickel, cadmium, zinc) on growth and performance of common bean ( Phaseolus vulgaris L. cv. Nebraska) plants before and after liming (CaCO 3 + MgCO 3 ) as soil correction treatment for the sake of remediation for heavy metal pollution in soil. Chemical analysis of carbohydrates showed significant increases in the contents of reducing sugars in response to lead, cadmium and nickel stress, which were decreased by liming treatments. The contents of total soluble sugars also increased in all heavy metal-treated plants but zinc. All heavy metals significantly lowered the leaf contents of the photosynthetic pigments (chlorophyll a, chlorophyll b and carotenoids). The sodium dodecyl sulphate polyacrylamide gel electrophoreseis (SDS-PAGE) of proteins indicated variations in the profile of electrophoretic protein bands in heavy metal-stressed common bean plants before and after liming. The results indicate that the investigated heavy metals were absorbed from the soil solution and then accumulated in the tissues of common bean plants in variable concentrations. The highest accumulation were lead (Pb) and chromium (Cr) then cadmium (Cd), zinc (Zn) and nickel (Ni) while the magnitude of limiting the retarding rate of absorption and accumulation was: Pb > Ni > Cr > Zn > Cd, respectively. Keywords : Heavy metals, common bean, liming, chlorophyll. African Journal of Biotechnology Vol. 12(29), pp. 4614-4622

Variation in carbon availability, defense chemistry and susceptibility to fungal invasion along the stems of mature trees

If carbon (C) sinks withdraw carbohydrates as they are transported along tree stems, carbohydrate availability may depend on local sink strength and distance from sources. Defenses, including monoterpenes--a major component of resin--limit the invasibility of pines. Since carbohydrate reserves fund monoterpene synthesis, we hypothesized that monoterpene concentrations in pine stems would decrease from the crown to the lower stem, and susceptibility to fungal infection would increase. Here, we measured carbohydrate and monoterpene concentrations along the stems of lodgepole pine trees (Pinus contorta var. latifolia) before inoculating with a blue-stain fungus at different heights. After 6 wk, we assessed tree responses to fungal infection based on lesion length and carbohydrate mobilization. Concentrations of carbohydrates and monoterpenes in the phloem before inoculation decreased with distance from the crown, whereas lesion lengths after inoculation increased. However, trees mobilized sugars in response to fungal infection such that carbohydrate reserves near lesions were similar at all heights. Despite C mobilization, the lower stem was more vulnerable than the upper stem. Consistent with predictions based on sink-source relationships, vulnerability occurred where carbohydrates were less available, and likely resulted from C withdrawal by sinks higher in the supply chain.

Dynamic O-GlcNAc modification regulates CREB-mediated gene expression and memory formation

The transcription factor CREB is a key regulator of many neuronal processes, including brain development, circadian rhythm, and long-term memory. Studies of CREB have focused on its phosphorylation, although the diversity of CREB functions in the brain suggests additional forms of regulation. Here we expand on a chemoenzymatic strategy for quantifying glycosylation stoichiometries to characterize the functional roles of CREB glycosylation in neurons. We show that CREB is dynamically O-GlcNAc-modified in response to neuronal activity and glycosylation represses CREB-dependent transcription by impairing its association with the co-activator CRTC/TORC. Blocking glycosylation of CREB altered cellular function and behavioral plasticity, enhancing both axonal and dendritic growth and long-term memory consolidation. Our findings demonstrate a new role for O-glycosylation in memory formation and provide a mechanistic understanding of how glycosylation contributes to critical neuronal functions. Moreover, we identify a previously unknown mechanism for the regulation of activity-dependent gene expression, neural development, and memory.

Rootstock-induced changes in the dry matter and carbohydrate contents of bearing shoots and flower buds in two Serbian plum cultivars

SummaryThe influence of the seedling rootstocks ‘Myrobalan’ and ‘Stanley’ on seasonal variability and the contents of dry matter (DM), starch (STA), and sugars [reducing (RS), non-reducing (NRS), and total (TS)] in bearing shoots (BS) and flower buds (FB) of ‘Čačanska lepotica’ and ‘Čačanska najbolja’ plum (Prunus domestica L.) were investigated. Regarding patterns of seasonal change, the decline in STA contents in BS and FB coincided with an increase in soluble sugars contents, and probably resulted from the conversion of starch to sugar in response to cooler temperatures. The more vigourous ‘Myrobalan’ rootstock induced higher STA contents in BS, and NRS contents in FB, whereas the less vigorous ‘Stanley’ rootstock induced higher sugars contents in BS, and DM and STA contents in FB. In contrast, ‘Čačanska lepotica’ had higher STA contents in FB, and sugars contents in BS, whereas ‘Čačanska najbolja’ had higher STA contents in BS, and NRS and TS contents in FB. The significant interactions observed between some treatments suggested that DM and carbohydrate contents in BS and FB did not depend on rootstock or cultivar, but on the combination, and on environmental conditions. Finally, BS had higher STA, NRS and TS contents, whereas FB had higher DM contents. RS contents were similar in both BS and FB.

Transcriptional and metabolic profiles of Lolium perenne L. genotypes in response to a PEG‐induced water stress

Metabolic profiling was carried out in the forage grass Lolium perenne L. (perennial ryegrass) to uncover mechanisms involved in the plants response to water stress. When leaf and root materials from two genotypes, with a contrasting water stress response, were analysed by GC-MS, a clear difference in the metabolic profiles of the leaf tissue under water stress was observed. Differences were principally due to a reduction in fatty acid levels in the more susceptible Cashel genotype and an increase in sugars and compatible solutes in the more tolerant PI 462336 genotype. Sugars with a significant increase included: raffinose, trehalose, glucose, fructose and maltose. Increasing the ability of perennial ryegrass to accumulate these sugars in response to a water deficit may lead to more tolerant varieties. The metabolomics approach was combined with a transcriptomics approach in the water stress tolerant genotype PI 462336, which has identified perennial ryegrass genes regulated under water stress.

The Drosophila foraging Gene Mediates Adult Plasticity and Gene–Environment Interactions in Behaviour, Metabolites, and Gene Expression in Response to Food Deprivation

Nutrition is known to interact with genotype in human metabolic syndromes, obesity, and diabetes, and also in Drosophila metabolism. Plasticity in metabolic responses, such as changes in body fat or blood sugar in response to changes in dietary alterations, may also be affected by genotype. Here we show that variants of the foraging (for) gene in Drosophila melanogaster affect the response to food deprivation in a large suite of adult phenotypes by measuring gene by environment interactions (GEI) in a suite of food-related traits. for affects body fat, carbohydrates, food-leaving behavior, metabolite, and gene expression levels in response to food deprivation. This results in broad patterns of metabolic, genomic, and behavioral gene by environment interactions (GEI), in part by interaction with the insulin signaling pathway. Our results show that a single gene that varies in nature can have far reaching effects on behavior and metabolism by acting through multiple other genes and pathways.

Search for Clinical Markers Could? Transform Alzheimer's Drug Research

Search for Clinical Markers Could? Transform Alzheimer's Drug Research

Alteration of oxidative and carbohydrate metabolism under abiotic stress in two rice ( Oryza sativa L.) genotypes contrasting in chilling tolerance

Abiotic stress is a major limiting factor in crop production. Physiological comparisons between contrasting abiotic stress-tolerant genotypes will improve understanding of stress-tolerant mechanisms. Rice seedlings (S3 stage) of a chilling-tolerant (CT) genotype (CT6748-8-CA-17) and a chilling-sensitive (CS) genotype (INIAP12) were subjected to abiotic stresses including chilling (13/12 degrees C), salt (100mM NaCl), and osmotic (200mM mannitol). Measures of physiological response to the stresses included changes in stress-related sugars, oxidative products and protective enzymes, parameters that could be used as possible markers for selection of improved tolerant varieties. Metabolite analyses showed that the two genotypes responded differently to different stresses. Genotype survival under chilling-stress was as expected, however, CT was more sensitive to salt stress than the CS genotype. The CT genotype was able to maintain membrane integrity better than CS, perhaps by reduction of lipid peroxidation via increased levels of antioxidant enzymes during chilling stress. This genotype accumulated sugars in response to stress, but the accumulation was usually less than in the CS genotype. Chill-stressed CT accumulated galactose and raffinose whereas these saccharides declined in CS. On the other hand, the tolerance mechanism in the more salt- and water-deficit-tolerant CS may be associated with accumulation of osmoprotectants such as glucose, trehalose and mannitol.

Analyzing the dynamic bacterial glycome with a lectin microarray approach

Glycosylation of bacterial cell surfaces is emerging as a critical factor in symbiosis, pathogenesis, cell-cell interactions and immune evasion. The lack of high-throughput analytical tools to examine bacterial glycans has been a major obstacle to the field and has hindered closer examination of the dynamics of carbohydrate variation. We have recently developed a lectin microarray for the analysis of glycoproteins. Herein we present a rapid analytical system based on this technology for the examination of bacterial glycans. The glycosylation pattern observed distinguishes closely related Escherichia coli strains from one another, providing a facile means of fingerprinting bacteria. In addition, dynamic alterations in the carbohydrate coat of a pathogenic E. coli strain are readily observed. The fast evaluation of real-time alterations in surface-carbohydrate epitopes allows examination of the dynamic role of bacterial sugars in response to external stimuli such as the immune system.