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1.
Food Chem ; 433: 137364, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37688819

RESUMO

This study aimed to investigate the influence of cyclic variable temperature conditioning (CVTC) on the rapid sweetening of sweet potato tuberous roots, as assessed through the analysis of sugar metabolism-related compounds and enzyme activities of tubers during storage. The results showed that CVTC effectively preserved the quality of sweet potato tuberous roots, leading to a significant elevation in soluble solids and soluble sugars. The CVTC group displayed sucrose and fructose levels that were 1.72 and 1.46 times higher, respectively, compared to the control group at the 8 d. Additionally, after storage, the activities of ß-amylase, sucrose phosphate synthase (SPS), and sucrose synthase (SS) in the CVTC group were increased by 19.85 %, 60.74 %, and 82.48 %, respectively. Conversely, acid convertase (AI) activity showed inhibition of 64.72 %. In conclusion, implementing CVTC enhanced enzymatic activity in ß-amylase, SPS, and SS, facilitating starch degradation and sucrose synthesis, which contributed to the overall improvement in the sweetness of sweet potato tubers.


Assuntos
Ipomoea batatas , beta-Amilase , Temperatura , Ipomoea batatas/metabolismo , beta-Amilase/metabolismo , Metabolismo dos Carboidratos , Sacarose/metabolismo , Amido/metabolismo
2.
Clin Ter ; 174(Suppl 2(6)): 200-208, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37994765

RESUMO

Background: Nutrigenomics - the study of the interactions between genetics and nutrition - has emerged as a pivotal field in personalized nutrition. Among various genetic variations, single-nucleotide polymorphisms (SNPs) have been extensively studied for their probable relationship with metabolic traits. Methods: Throughout this review, we have employed a targeted research approach, carefully handpicking the most representative and relevant articles on the subject. Our methodology involved a systematic review of the scientific literature to ensure a comprehensive and accurate overview of the available sources. Results: SNPs have demonstrated a significant influence on lipid metabolism, by impacting genes that encode for enzymes involved in lipid synthesis, transport, and storage. Furthermore, they have the ability to affect enzymes in glycolysis and insulin signaling pathways: in a way, they can influence the risk of type 2 diabetes. Thanks to recent advances in genotyping technologies, we now know numerous SNPs linked to lipid and carbohydrate metabolism. The large-scale studies on this topic have unveiled the potential of personalized dietary recommendations based on an individual's genetic makeup. Personalized nutritional interventions hold promise to mitigate the risk of various chronic diseases; however, translating these scientific insights into actionable dietary guidelines is still challenging. Conclusions: As the field of nutrigenomics continues to evolve, collaborations between geneticists, nutritionists, and healthcare providers are essential to harness the power of genetic information for improving metabolic health. By unraveling the genetic basis of metabolic responses to diet, this field holds the potential to revolutionize how we approach dietary recommendations and preventive healthcare practices.


Assuntos
Diabetes Mellitus Tipo 2 , Nutrigenômica , Humanos , Polimorfismo de Nucleotídeo Único , Dieta , Lipídeos , Metabolismo dos Carboidratos
3.
Nucleic Acids Res ; 51(21): 11952-11966, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37850640

RESUMO

Synthetic regulation of metabolic fluxes has emerged as a common strategy to improve the performance of microbial cell factories. The present regulatory toolboxes predominantly rely on the control and manipulation of carbon pathways. Nitrogen is an essential nutrient that plays a vital role in growth and metabolism. However, the availability of broadly applicable tools based on nitrogen pathways for metabolic regulation remains limited. In this work, we present a novel regulatory system that harnesses signals associated with nitrogen metabolism to redirect excess carbon flux in Bacillus licheniformis. By engineering the native transcription factor GlnR and incorporating a sorbitol-responsive element, we achieved a remarkable 99% inhibition of the expression of the green fluorescent protein reporter gene. Leveraging this system, we identified the optimal redirection point for the overflow carbon flux, resulting in a substantial 79.5% reduction in acetoin accumulation and a 2.6-fold increase in acetate production. This work highlight the significance of nitrogen metabolism in synthetic biology and its valuable contribution to metabolic engineering. Furthermore, our work paves the way for multidimensional metabolic regulation in future synthetic biology endeavors.


Assuntos
Bacillus licheniformis , Bacillus licheniformis/genética , Bacillus licheniformis/metabolismo , Carbono/metabolismo , Nitrogênio/metabolismo , Metabolismo dos Carboidratos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Engenharia Metabólica/métodos
4.
Sheng Wu Gong Cheng Xue Bao ; 39(9): 3566-3578, 2023 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-37805838

RESUMO

As specialized intracellular parasite, viruses have no ability to metabolize independently, so they completely depend on the metabolic mechanism of host cells. Viruses use the energy and precursors provided by the metabolic network of the host cells to drive their replication, assembly and release. Namely, viruses hijack the host cells metabolism to achieve their own replication and proliferation. In addition, viruses can also affect host cell metabolism by the expression of auxiliary metabolic genes (AMGs), affecting carbon, nitrogen, phosphorus, and sulfur cycles, and participate in microbial-driven biogeochemical cycling. This review summarizes the effect of viral infection on the host's core metabolic pathway from four aspects: cellular glucose metabolism, glutamine metabolism, fatty acid metabolism, and viral AMGs on host metabolism. It may facilitate in-depth understanding of virus-host interactions, and provide a theoretical basis for the treatment of viral diseases through metabolic intervention.


Assuntos
Redes e Vias Metabólicas , Viroses , Humanos , Metabolismo dos Carboidratos , Interações entre Hospedeiro e Microrganismos , Metabolismo dos Lipídeos
5.
Front Endocrinol (Lausanne) ; 14: 1245629, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37876534

RESUMO

Background: Glucose metabolism (GM) plays a crucial role in cancer cell proliferation, tumor growth, and survival. However, the identification of glucose metabolism-related genes (GMRGs) for effective prediction of prognosis in head and neck squamous cell carcinoma (HNSC) is still lacking. Methods: We conducted differential analysis between HNSC and Normal groups to identify differentially expressed genes (DEGs). Key module genes were obtained using weighted gene co-expression network analysis (WGCNA). Intersection analysis of DEGs, GMRGs, and key module genes identified GMRG-DEGs. Univariate and multivariate Cox regression analyses were performed to screen prognostic-associated genes. Independent prognostic analysis of clinical traits and risk scores was implemented using Cox regression. Gene set enrichment analysis (GSEA) was used to explore functional pathways and genes between high- and low-risk groups. Immune infiltration analysis compared immune cells between the two groups in HNSC samples. Drug prediction was performed using the Genomics of Drug Sensitivity in Cancer (GDSC) database. Quantitative real-time fluorescence PCR (qRT-PCR) validated the expression levels of prognosis-related genes in HNSC patients. Results: We identified 4973 DEGs between HNSC and Normal samples. Key gene modules, represented by black and brown module genes, were identified. Intersection analysis revealed 76 GMRG-DEGs. Five prognosis-related genes (MTHFD2, CDKN2A, TPM2, MPZ, and DNMT1) were identified. A nomogram incorporating age, lymph node status (N), and risk score was constructed for survival prediction in HNSC patients. Immune infiltration analysis showed significant differences in five immune cell types (Macrophages M0, memory B cells, Monocytes, Macrophages M2, and Dendritic resting cells) between the high- and low-risk groups. GDSC database analysis identified 53 drugs with remarkable differences between the groups, including A.443654 and AG.014699. DNMT1 and MTHFD2 were up-regulated, while MPZ was down-regulated in HNSC. Conclusion: Our study highlights the significant association of five prognosis-related genes (MTHFD2, CDKN2A, TPM2, MPZ, and DNMT1) with HNSC. These findings provide further evidence of the crucial role of GMRGs in HNSC.


Assuntos
Metabolismo dos Carboidratos , Neoplasias de Cabeça e Pescoço , Humanos , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/genética , Glucose
6.
Int J Food Microbiol ; 407: 110421, 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-37806010

RESUMO

Sourdough fermentation, one of the oldest unit operations in food production, is currently experiencing a revival in bread production at the household, artisanal, and the industrial level. The expanding use of sourdough fermentation in bread production and the adaptation of fermentation to large scale industrial bread production also necessitate the development of novel starter cultures. Developments in the last years also have expanded the tools that are used to assess the metabolic potential of specific strains, species or genera of the Lactobacillaceae and have identified multiple ecological and metabolic traits as clade-specific. This review aims to provide an overview on the clade-specific metabolic potential of members of the Lactobacillaceae for use in sourdough baking, and the impact of these clade-specific traits on bread quality. Emphasis is placed on carbohydrate metabolism, including the conversion of sucrose and starch to soluble polysaccharides, conversion of amino acids, and the metabolism of organic acids. The current state of knowledge to compose multi-strain starter cultures (synthetic microbial communities) that are suitable for back-slopping will also be discussed. Taken together, the communication outlines the current tools for selection of microbes for use in sourdough baking.


Assuntos
Pão , Lactobacillus , Lactobacillus/metabolismo , Pão/análise , Lactobacillaceae , Fermentação , Metabolismo dos Carboidratos , Microbiologia de Alimentos
7.
PLoS One ; 18(10): e0292959, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37831703

RESUMO

To evaluated the effects melatonin (MT) on the sugar and acid metabolism of early-ripening peach fruits, the concentration of 150 µmol/L MT was sprayed on the leaves of peach trees. MT increased the contents of total soluble sugar and sucrose in peach fruits during the whole ripening period, and increased the contents of glucose and sorbitol at the mature stage. During the whole ripening period, MT also increased the activities of sucrose synthase, sucrose phosphate synthase, neutral invertase, and acidic invertase and the relative expression levels of sucrose synthase, sucrose phosphate synthase, neutral invertase, and acidic invertase genes, while decreased the activity of sorbitol oxidase and the relative expression level of sorbitol dehydrogenase to some extent. Moreover, MT decreased the contents of total organic acid, malic acid, and citric acid at mature stage. At mature stage, MT decreased the activities of citrate synthetase and phosphoenolpyruvate carboxylase and the relative expression levels of citrate synthetase and phosphoenolpyruvate carboxylase genes, while increased the relative expression levels of Nicotinamide adenine dinucleotide phosphate (NADP+)-malic enzyme, malate dehydrogenase, and aconitase genes. Therefore, MT promotes the sugar accumulation and organic acid degradation in early-ripening peach fruits.


Assuntos
Frutas , Melatonina , Açúcares/metabolismo , Metabolismo dos Carboidratos , Melatonina/farmacologia , Fosfoenolpiruvato Carboxilase/metabolismo , beta-Frutofuranosidase , Carboidratos/farmacologia , Citratos/farmacologia , Ligases/metabolismo
8.
Adv Gerontol ; 36(3): 397-401, 2023.
Artigo em Russo | MEDLINE | ID: mdl-37782648

RESUMO

Aging normally leads to profound changes in the homeostasis of carbohydrate metabolism, which is considered a good predictor of health state and life expectancy. The objective of this study was assessing main indicators of carbohydrate metabolism in Northern men of older ages living under conditions of the North-Eastern region of Russia (Magadan). The results of the study showed carbohydrate disorders in healthy elderly men who exhibited high values of fasting plasma glucose (5,81±0,20 mmol/L) and glycosylated hemoglobin (5,73±0,12%), mainly owing to elevated insulin resistance (HOMA-IR was 2,63±0,25 arb. units), and not to reduced pancreatic ß-cells function (HOMA-ß was 96,85±6,10%), in the absence of a compensatory increase in basal insulin levels (9,97±0,81 µm/mL). Carbohydrate metabolism tenduence in healthy elderly men appears to worsen cardiometabolic health in older residents of the North. Our data confirm those by other authors and indicate the formation of age-associated pathology that causes accelerated aging of the body.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Masculino , Humanos , Idoso , Glicemia , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Resistência à Insulina/fisiologia , Metabolismo dos Carboidratos , Insulina , Diabetes Mellitus Tipo 2/metabolismo
9.
PLoS Biol ; 21(10): e3002329, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37847672

RESUMO

Extra-intestinal pathogenic Escherichia coli (ExPEC) can cause a variety of infections outside of the intestine and are a major causative agent of urinary tract infections. Treatment of these infections is increasingly frustrated by antimicrobial resistance (AMR) diminishing the number of effective therapies available to clinicians. Incidence of multidrug resistance (MDR) is not uniform across the phylogenetic spectrum of E. coli. Instead, AMR is concentrated in select lineages, such as ST131, which are MDR pandemic clones that have spread AMR globally. Using a gnotobiotic mouse model, we demonstrate that an MDR E. coli ST131 is capable of out-competing and displacing non-MDR E. coli from the gut in vivo. This is achieved in the absence of antibiotic treatment mediating a selective advantage. In mice colonised with non-MDR E. coli strains, challenge with MDR E. coli either by oral gavage or co-housing with MDR E. coli colonised mice results in displacement and dominant intestinal colonisation by MDR E. coli ST131. To investigate the genetic basis of this superior gut colonisation ability by MDR E. coli, we assayed the metabolic capabilities of our strains using a Biolog phenotypic microarray revealing altered carbon metabolism. Functional pangenomic analysis of 19,571 E. coli genomes revealed that carriage of AMR genes is associated with increased diversity in carbohydrate metabolism genes. The data presented here demonstrate that independent of antibiotic selective pressures, MDR E. coli display a competitive advantage to colonise the mammalian gut and points to a vital role of metabolism in the evolution and success of MDR lineages of E. coli via carriage and spread.


Assuntos
Infecções por Escherichia coli , Escherichia coli , Animais , Camundongos , Filogenia , Farmacorresistência Bacteriana Múltipla/genética , Antibacterianos/farmacologia , Variação Genética , Metabolismo dos Carboidratos/genética , Mamíferos
10.
Biochem Biophys Res Commun ; 682: 193-198, 2023 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-37820455

RESUMO

Maternal consumption of low-protein (LP) diet during pregnancy has been demonstrated to increase the chances of adult offspring developing metabolic syndrome, and this risk can be exacerbated when the postnatal diets do not align with the prenatal conditions. However, in our previous study, focusing on serum parameters and gene expression patterns within adipose tissue, we discovered the presence of "healthy obesity" in young adult offspring from dams that were fed an LP, as a response to a postweaning high-fat (HF) diet. Here, we subsequently investigated the role played by the liver and skeletal muscle in alleviation of insulin resistance in male offspring that were fed either control (C/C group) or HF diet (C/HF and LP/HF groups) for 22 weeks. While a postweaning HF diet increased liver weight and hepatic triglyceride (TG) and cholesterol levels in offspring of control dams, these levels were lower in the LP/HF group compared to the C/HF group. Analysis of the liver transcriptome identified 430 differentially expressed genes (DEGs) in the LP/HF and C/HF comparison. Especially, downregulated DEGs were enriched in carbohydrate metabolism and the levels of DEGs were significantly correlated with the levels of markers for serum glucose homeostasis and hepatic lipid accumulation. In the LP/HF group compared to the C/HF group, there was a decrease in the gastrocnemius muscle weight, while no differences were observed in gene expression levels associated with muscle fiber phenotype, mitochondrial function, and inflammation. In conclusion, maternal LP diet induced changes in lipid and glucose metabolism within the liver, similar to what was observed in adipose tissue, while there were no alterations in metabolic functions in the skeletal muscle in young offspring mice fed an HF diet. Further research that investigating the enduring impact of nutritional transition on offspring is essential to gain a comprehensive grasp of developmental programming throughout their entire lifespan.


Assuntos
Dieta Hiperlipídica , Efeitos Tardios da Exposição Pré-Natal , Gravidez , Humanos , Feminino , Camundongos , Animais , Masculino , Dieta Hiperlipídica/efeitos adversos , Dieta com Restrição de Proteínas/efeitos adversos , Fenômenos Fisiológicos da Nutrição Materna , Efeitos Tardios da Exposição Pré-Natal/genética , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Fígado/metabolismo , Triglicerídeos/metabolismo , Glucose/metabolismo , Metabolismo dos Carboidratos , Expressão Gênica , Metabolismo dos Lipídeos/genética
11.
Wiad Lek ; 76(9): 1913-1921, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37898925

RESUMO

OBJECTIVE: The aim: Analyse the impact and effectiveness of cognitive-behavioural therapy in patients with NAFLD on the background of AO on indicators of lipid and carbohydrate metabolism. PATIENTS AND METHODS: Materials and methods: 85 patients with NAFLD and obesity of the 1st degree (42 women, 43 men) were examined. All patients were divided into two clinical groups: 1st group (research) - 48 people, who underwent a course of CBT for 6 months; the control group - 37 people, who followed only diet therapy, recommended physical activity, without involvement in CBT. The general clinical examination of patients consisted of the measurement of anthropometric and physiological indicators, the study of lipid and carbohydrate profile indicators. RESULTS: Results: After a 6-month course of CBT, a decrease in the atherogenic coefficient (AC) was recorded in the patients of the 1st group in 2.29 times (p=0.037<0.05), the number of patients with hypertension of the 1st degree decreased in 1.8 times (p=0.0047<0.05) in comparison with the initial indicators (on the 1st day) and amount of patients with normal blood pressure of the 1st group increased by 2.4 times (p=0.0115<0.05) compared to the control group. CONCLUSION: Conclusions: The course of CBT should be an integral component in the program for the management of obese patients to optimize not only the psycho-emo¬tional condition, but also to correct lipid and carbohydrate metabolism indicators, reduce the risk of developing cardiovascular and neurological complications.


Assuntos
Terapia Cognitivo-Comportamental , Hepatopatia Gordurosa não Alcoólica , Masculino , Humanos , Feminino , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/terapia , Obesidade Abdominal/complicações , Obesidade/complicações , Obesidade/terapia , Metabolismo dos Carboidratos , Lipídeos , Índice de Massa Corporal
12.
Biomolecules ; 13(10)2023 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-37892154

RESUMO

Hypoxic-ischaemic encephalopathy (HIE) is an important cause of morbidity and mortality globally. Although mild therapeutic hypothermia (TH) may improve outcomes in selected babies, the mechanism of action is not fully understood. A proteomics discovery study was carried out to analyse proteins in the plasma of newborns with HIE. Proteomic analysis of plasma from 22 newborns with moderate-severe HIE that had initially undergone TH, and relative controls including 10 newborns with mild HIE who did not warrant TH and also cord blood from 10 normal births (non-HIE) were carried out using the isobaric Tandem Mass Tag (TMT®) 10plexTM labelling with tandem mass spectrometry. A total of 7818 unique peptides were identified in all TMT10plexTM samples, translating to 3457 peptides representing 405 proteins, after applying stringent filter criteria. Apart from the unique protein signature from normal cord blood, unsupervised analysis revealed several significantly regulated proteins in the TH-treated moderate-severe HIE group. GO annotation and functional clustering revealed various proteins associated with glucose metabolism: the enzymes fructose-bisphosphate aldolase A, glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate mutase 1, phosphoglycerate kinase 1, and pyruvate kinase PKM were upregulated in newborns with favourable (sHIE+) outcomes compared to newborns with unfavourable (sHIE-) outcomes. Those with favourable outcomes had normal MR imaging or mild abnormalities not predictive of adverse outcomes. However, in comparison to mild HIE and the sHIE- groups, the sHIE+ group had the additional glucose metabolism-related enzymes upregulated, including triosephosphate isomerase, α-enolase, 6-phosphogluconate dehydrogenase, transaldolase, and mitochondrial glutathione reductase. In conclusion, our plasma proteomic study demonstrates that TH-treated newborns with favourable outcomes have an upregulation in glucose metabolism. These findings may open new avenues for more effective neuroprotective therapy.


Assuntos
Asfixia , Proteômica , Lactente , Humanos , Recém-Nascido , Metabolismo dos Carboidratos , Espectrometria de Massas em Tandem , Peptídeos
13.
Physiol Plant ; 175(5): e14001, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37882295

RESUMO

In trees, nonstructural carbohydrates (NSCs) serve as long-term carbon storage and long-distance carbon transport from source to sink. NSC management in response to drought stress is key to our understanding of drought acclimation. However, the molecular mechanisms underlying these processes remain unclear. By combining a transcriptomic approach with NSC quantification in the leaves, stems, and roots of Populus alba under drought stress, we analyzed genes from 29 gene families related to NSC signaling, translocation, and metabolism. We found starch depletion across organs and accumulation of soluble sugars (SS) in the leaves. Activation of the trehalose-6-phosphate/SNF1-related protein kinase (SnRK1) signaling pathway across organs via the suppression of class I TREHALOSE-PHOSPHATE SYNTHASE (TPS) and the expression of class II TPS genes suggested an active response to drought. The expression of SnRK1α and ß subunits, and SUCROSE SYNTHASE6 supported SS accumulation in leaves. The upregulation of active transporters and the downregulation of most passive transporters implied a shift toward active sugar transport and enhanced regulation over partitioning. SS accumulation in vacuoles supports osmoregulation in leaves. The increased expression of sucrose synthesis genes and reduced expression of sucrose degradation genes in the roots did not coincide with sucrose levels, implying local sucrose production for energy. Moreover, the downregulation of invertases in the roots suggests limited sucrose allocation from the aboveground organs. This study provides an expression atlas of NSC-related genes that respond to drought in poplar trees, and can be tested in tree improvement programs for adaptation to drought conditions.


Assuntos
Populus , Árvores , Árvores/metabolismo , Populus/genética , Populus/metabolismo , Secas , Carboidratos , Metabolismo dos Carboidratos/genética , Sacarose/metabolismo , Açúcares , Carbono
14.
Rev. psicol. deport ; 32(3): 212-222, Sept 3, 2023. ilus, tab, graf
Artigo em Inglês | IBECS | ID: ibc-227458

RESUMO

Hypertension may also be referred to as essential hypertension. The circulatory movement is in its early stages. Hypertension is a self-contained systemic ailment characterised by elevated arterial blood pressure, leading to detrimental effects on various organs such as the heart, brain, kidneys, and other bodily systems. The term "high" refers to a state or condition that is elevated or above average. Hypertension is a prevalent and highly morbid condition within the cardiovascular system. The prevalence of hypertension in our nation is experiencing an upward trend, with a concomitant rise in the proportion of hypertensive adults observed annually. Currently, the predominant approach to managing hypertension in our nation revolves around pharmacological interventions; however, it is worth noting that these drug treatments are associated with certain adverse effects. In the long term, there is a significant fluctuation in blood pressure following discontinuation. There is an urgent need for an improvement to be made regarding this particular phenomenon. The objective of this study is to examine the impact of aerobic exercise on stress levels, quality of life, and lipid and glucose metabolism among hypertensive adults. A total of 92 individuals diagnosed with hypertension were assigned to two groups: a control group consisting of 46 participants, and a study group also consisting of 46 participants. The allocation of individuals to each group was determined based on digital criteria. Both cohorts were administered a regimen of pharmaceutical compounds, with the experimental group additionally engaging in aerobic exercise as an adjunctive intervention.(AU)


Assuntos
Humanos , Masculino , Feminino , Hipertensão , Exercício Físico , Metabolismo dos Carboidratos , Metabolismo dos Lipídeos , Saúde Mental , Psicologia do Esporte , Esportes , Qualidade de Vida , Estudos de Coortes , Inquéritos e Questionários , Autoavaliação (Psicologia)
15.
Int J Biol Macromol ; 253(Pt 4): 126961, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37722637

RESUMO

In this study, bacterial cellulose/gum Arabic composite (BC/GA) was synthesized by in-situ modification from lavender residue hydrolysate for the first time. The in-situ modification with GA adding showed great beneficial effect for BC/GA synthesis. Both the product (BC or BC/GA) yield and the product (BC or BC/GA) production per sugars consumption increased greatly by the in-situ modification when compared with the fermentation without GA adding (2.90 g/L vs. 0.91 g/L, and 0.461 g/g vs. 0.138 g/g). It is hypothesized that the combination of BC and GA is the main mechanism for the beneficial effect of the in-situ modification, and the scanning electron microscope (SEM) images confirmed this hypothesis. GA adding showed little effect on the rheological properties of lavender residue hydrolysate, and this environment was suitable for the combination of BC and GA. The in-situ modification had an obvious influence on the crystallinity index and the thermal stability of BC/GA, but affected little on its functional groups and cellulose structural framework. Besides BC/GA synthesis and structure, the in-situ modification could also alter the texture properties of BC/GA. Overall, this study can offer some useful information for the biochemical conversion from green and cost-effective lavender residue hydrolysate to attractive biomaterial BC/GA.


Assuntos
Celulose , Lavandula , Celulose/química , Goma Arábica , Fermentação , Metabolismo dos Carboidratos , Bactérias/metabolismo
16.
Commun Biol ; 6(1): 961, 2023 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-37735577

RESUMO

Most Gram-negative bacteria synthesize osmo-regulated periplasmic glucans (OPG) in the periplasm or extracellular space. Pathogenicity of many pathogens is lost by knocking out opgG, an OPG-related gene indispensable for OPG synthesis. However, the biochemical functions of OpgG and OpgD, a paralog of OpgG, have not been elucidated. In this study, structural and functional analyses of OpgG and OpgD from Escherichia coli revealed that these proteins are ß-1,2-glucanases with remarkably different activity from each other, establishing a new glycoside hydrolase family, GH186. Furthermore, a reaction mechanism with an unprecedentedly long proton transfer pathway among glycoside hydrolase families is proposed for OpgD. The conformation of the region that forms the reaction pathway differs noticeably between OpgG and OpgD, which explains the observed low activity of OpgG. The findings enhance our understanding of OPG biosynthesis and provide insights into functional diversity for this novel enzyme family.


Assuntos
Glicosídeo Hidrolases , Proteínas Periplásmicas , Glicosídeo Hidrolases/genética , Escherichia coli/genética , Metabolismo dos Carboidratos , Espaço Extracelular , Glucanos
17.
Metab Eng ; 80: 12-24, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37678664

RESUMO

The capability of cyanobacteria to produce sucrose from CO2 and light has a remarkable societal and biotechnological impact since sucrose can serve as a carbon and energy source for a variety of heterotrophic organisms and can be converted into value-added products. However, most metabolic engineering efforts have focused on understanding local pathway alterations that drive sucrose biosynthesis and secretion in cyanobacteria rather than analyzing the global flux re-routing that occurs following induction of sucrose production by salt stress. Here, we investigated global metabolic flux alterations in a sucrose-secreting (cscB-overexpressing) strain relative to its wild-type Synechococcus elongatus 7942 parental strain. We used targeted metabolomics, 13C metabolic flux analysis (MFA), and genome-scale modeling (GSM) as complementary approaches to elucidate differences in cellular resource allocation by quantifying metabolic profiles of three cyanobacterial cultures - wild-type S. elongatus 7942 without salt stress (WT), wild-type with salt stress (WT/NaCl), and the cscB-overexpressing strain with salt stress (cscB/NaCl) - all under photoautotrophic conditions. We quantified the substantial rewiring of metabolic fluxes in WT/NaCl and cscB/NaCl cultures relative to WT and identified a metabolic bottleneck limiting carbon fixation and sucrose biosynthesis. This bottleneck was subsequently mitigated through heterologous overexpression of glyceraldehyde-3-phosphate dehydrogenase in an engineered sucrose-secreting strain. Our study also demonstrates that combining 13C-MFA and GSM is a useful strategy to both extend the coverage of MFA beyond central metabolism and to improve the accuracy of flux predictions provided by GSM.


Assuntos
Engenharia Metabólica , Synechococcus , Cloreto de Sódio/metabolismo , Metabolismo dos Carboidratos , Synechococcus/genética , Synechococcus/metabolismo , Sacarose/metabolismo , Fotossíntese
18.
Pestic Biochem Physiol ; 195: 105568, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37666622

RESUMO

Afidopyropen has strong insecticidal toxicity to sucking pests by silencing the vanilloid-type transient receptor potential (TRPV) channels. However, the toxicity of afidopyropen to the Lepidoptera model insect silkworm remain unknown. In this study, the LC50 of afidopyropen to the silkworm at 72 h exposure was 256.82 mg/L. This indicates that afidopyropen is moderately toxic to the silkworm. Long-term exposure to concentrations of 100 mg/L, or less, of afidopyropen, significantly reduced silkworm growth, vitality, silk protein synthesis, and fecundity. A total of 220 differentially expressed genes (DEGs) were detected by transcriptome sequencing, among which 166 were downregulated and 54 were upregulated. Gene Ontology (GO) enrichment analysis showed that the DEGs were enriched in the immune system, immune response and carbohydrate metabolism. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis indicated that DEGs were primarily concentrated in carbohydrate metabolism and biosynthesis of neomycin, kanamycin and gentamicin. Genes related to carbohydrate metabolism and immune system pathways in silkworm were detected by quantitative real-time PCR. The results showed that the genes related to carbohydrate metabolism, silk protein synthesis, and immune response were significantly downregulated. These genes included BCL-6 corepressor-like protein 1 (BCORL1), hexokinase type 2 (HEXO2), phosphoserine aminotransferase 1 (PSAT1), relish (Rel), peptidoglycan recognition protein 2 (PGRP2) and 27 kda glycoprotein precursor (P27K). The data demonstrated the toxic effects of afidopyropen against the silkworm and its regulation of genes responsible for immune function and abscissa carbohydrate metabolism.


Assuntos
Bombyx , Animais , Bombyx/genética , Metabolismo dos Carboidratos , Seda , Imunidade
19.
Pestic Biochem Physiol ; 195: 105570, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37666623

RESUMO

The general cutworm, Spodoptera litura (Lepidoptera: Noctuidae) is a worldwide destructive omnivorous pest and the endoparasitoid wasp Meteorus pulchricornis (Hymenoptera: Braconidae) is the dominant endoparasitoid of S. litura larvae. Trehalase is a key enzyme in insect trehalose metabolism and plays an important role in the growth and development of insects. However, the specific function of trehalase in parasitoid and host associations has been less reported. In this study, we obtained two trehalase genes (SlTre1 and SlTre2) from our previously constructed S. litura transcriptome database; they were highly expressed in 3rd instar larvae. SlTre1 was mainly expressed in the midgut, and SlTre2 was expressed highest in the head. SlTre1 and SlTre2 were highly expressed 5 days after parasitization by M. pulchricornis. Treatment with the trehalase inhibitor validamycin A significantly inhibited the expression levels of SlTre1 and SlTre2, and the trehalase activity. Besides, the content of trehalose was increased but the content of glucose was decreased 24 h after validamycin A treatment in parasitized S. litura larvae. In addition, the immune-related genes in phenoloxidase (PO) pathway and fatty acid synthesis-related genes in lipid metabolism were upregulated in parasitized host larvae after validamycin A treatment. Importantly, the emergence rate, proportion of normal adults, and body size of parasitoid offspring was decreased in parasitized S. litura larvae after validamycin A treatment, indicating that validamycin A disrupts the trehalose metabolism of parasitized host and thus reduces the fitness of parasitoid offspring. The present study provides a novel perspective for coordinating the application of biocontrol and antibiotics in agroecosystem.


Assuntos
Trealase , Trealose , Animais , Trealase/genética , Metabolismo dos Carboidratos , Larva
20.
Proc Natl Acad Sci U S A ; 120(38): e2300366120, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37695897

RESUMO

Immune cell-based cancer therapies, such as chimeric antigen receptor T (CAR-T)-cell immunotherapy, have demonstrated impressive potency against hematological tumors. However, the efficacy of CAR-T cells against solid tumors remains limited. Herein, we designed tumor-targeting molecule-sialidase conjugates that potently and selectively stripped different sialoglycans from a variety of cancer cells. Desialylation enhanced induced pluripotent stem cell-derived chimeric antigen receptor-macrophage (CAR-iMac) infiltration and activation. Furthermore, the combination of cancer cell desialylation and CAR-iMac adoptive cellular therapy exerted a dramatic therapeutic effect on solid tumors and significantly prolonged the survival of tumor-bearing mice; these effects were mainly dependent on blockade of the checkpoint composed of sialic acid-binding immunoglobulin-like lectin (Siglec)-5 and Siglec-10 on the macrophages, and knockout of the glycoimmune checkpoint receptors could construct a CAR-iMac cell with stronger anticancer activity. This strategy that reverts the immune escape state ("cold tumor") to a sensitive recognition state ("hot tumor") has great significance for enhancing the effect of cellular immunotherapy on solid tumors. Therefore, desialylation combined with CAR-iMac cellular immunotherapy is a promising approach to enhance treatment with cellular immunotherapy and expand the valid indications among solid tumors, which provides inspiration for the development of cellular immunotherapies with glycoimmune checkpoint inhibition for the treatment of human cancer.


Assuntos
Neoplasias , Receptores de Antígenos Quiméricos , Humanos , Animais , Camundongos , Imunoterapia , Neoplasias/terapia , Metabolismo dos Carboidratos , Polissacarídeos
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