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Field pea seeds have long been recognized as valuable feed ingredients for animal diets, due to their high-quality protein and starch digestibility. However, the chemical composition of pea cultivars can vary across different growing locations, consequently impacting their nutrient profiles. This study employs untargeted metabolomics in conjunction with the quantification of fatty acids and amino acids to explore the influence of three different growing locations in Spain (namely Andalusia, Aragon and Asturias), on the nutritional characteristics of seeds of various pea cultivars. Significant interactions between cultivar and environment were observed, with 121 metabolites distinguishing pea profiles. Lipids, lipid-like molecules, phenylpropanoids, polyketides, carbohydrates, and amino acids were the most affected metabolites. Fatty acid profiles varied across locations, with higher C16:0, C18:0, and 18:1 n-9 concentration in Aragón, while C18:2 n-6 predominated in Asturias and C18:3 n-3 in Andalusia. Amino acid content was also location-dependent, with higher levels in Asturias. These findings underscore the impact of environmental factors on pea metabolite profiles and emphasize the importance of selecting pea cultivars based on specific locations and animal requirements. Enhanced collaboration between research and industry is crucial for optimizing pea cultivation for animal feed production.

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Lupus nephritis (LN) is an immunoinflammatory glomerulonephritis associated with renal involvement in systemic lupus erythematosus (SLE). Given the close relationship between plasma amino acids (AAs) and renal function, this study aimed to elucidate the plasma AA profiles in LN patients and identify key AAs and diagnostic patterns that distinguish LN patients from those with SLE and healthy controls. Participants were categorized into three groups: normal controls (NC), SLE, and LN. Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was employed to quantify AA levels in human plasma. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were utilized to identify key AAs. The diagnostic capacity of the models was assessed using receiver operating characteristic (ROC) curve analysis and area under the ROC curve (AUC) values. Significant alterations in plasma AA profiles were observed in LN patients compared to the SLE and NC groups. The OPLS-DA model effectively separated LN patients from the SLE and NC groups. A joint model using histidine (His), lysine (Lys), and tryptophan (Trp) demonstrated exceptional diagnostic performance, achieving an AUC of 1.0 with 100% sensitivity, specificity, and accuracy in predicting LN. Another joint model comprising arginine (Arg), valine (Val), and Trp also exhibited robust predictive performance, with an AUC of 0.998, sensitivity of 93.80%, specificity of 100%, and accuracy of 95.78% in distinguishing between SLE and LN. The joint forecasting models showed excellent predictive capabilities in identifying LN and categorizing lupus disease status. This approach provides a novel perspective for the early identification, prevention, treatment, and management of LN based on variations in plasma AA levels.

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BACKGROUND: Soy-based meat alternatives (SBMA) are becoming increasingly popular, but it is unclear if they have the same anabolic effect on skeletal muscle as animal meat. OBJECTIVES: We aimed to compare the stimulation of skeletal muscle protein synthesis by consumption of 1 or two 4 oz patties of SBMA with 4 oz (80% protein/20% fat) beef. METHODS: The study design was a randomized controlled trial. Participants were aged 18-40 y of age and in good general health with a body mass index (kg/m2) between 20 and 32. Stable isotope tracer methods were used (L-[ring-2H5] phenylalanine, [U-13C9-15N]- tyrosine, and L-[ring-2H4] tyrosine) to quantify the response of muscle protein fractional synthetic rate (FSR) to consumption of a single beef (4 oz), single SBMA (4 oz), or two 4 oz SBMA patties (8 oz). Whole-body rates of protein synthesis, breakdown, and net balance, as well as plasma essential amino acid concentrations, were also measured. RESULTS: The increase above basal in muscle protein FSR following consumption of the 4 oz beef patty (0.020 ± 0.016%/h) was significantly greater than the increase following consumption of 4 oz SBMA (P = 0.021; 0.003 ± 0.010%/h) but not 8 oz SBMA (P = 0.454; 0.013 ± 0.016%/h). The maximal essential amino acid concentration was significantly correlated (P = 0.046; r = 0.411) with the change in muscle FSR from the basal to the postprandial period. In addition, the change in muscle FSR from the basal to postprandial period was significantly correlated (P = 0.046; r = 0.412) with the corresponding change in whole-body protein synthesis. CONCLUSIONS: Consumption of a 4 oz beef patty stimulates muscle and whole-body protein synthesis >4 oz SBMA patty and similarly to 8 oz of SBMA. This trial was registered at clinicaltrials.gov as NCT05197140.

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Breast cancer (BC) is among the most commonly diagnosed cancers. Besides mammography, breast ultrasonography and the routinely monitored protein markers, the variations of small molecular metabolites in blood may be of great diagnostic value. This study aimed to quantify specific metabolite markers with potential application in BC detection. The study enrolled 50 participants, 25 BC patients and 25 healthy controls (CTRL). Dried blood spots (DBS) were utilized as biological media and were quantified via a simplified liquid chromatography tandem mass spectrometry (LC-MS/MS) method, used in expanded newborn screening. The targeted metabolomic analysis included 12 amino acids and 32 acylcarnitines. Statistical analysis revealed a significant variation of metabolic profiles between BC patients and CTRL. Among the 44 metabolites, 18 acylcarnitines and 10 amino acids remained significant after Bonferroni correction, showing increase or decrease and enabled classification of BC patients and CTRL. The well-established LC-MS/MS protocol could provide results within few minutes. Therefore, the combination of an easy-to-handle material-DBS and LC-MS/MS protocol could facilitate BC screening/diagnosis and in the next step applied to other cancer patients, as well.

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Hepatic amino acid (AA) metabolism and glucagon secretion are linked in a feedback cycle in which circulating AAs stimulate glucagon secretion, while glucagon stimulates hepatic AA catabolism. It has been proposed that metabolic dysfunction-associated steatotic liver disease (MASLD) leads to hepatic glucagon resistance, which may result in hyperaminoacidemia and hyperglucagonemia. We tested the glucagon effect on AA metabolism in subjects with obesity; 11 with steatohepatitis (MASH), 10 with steatosis (MAS), and seven subjects (CON) without steatosis. We performed a somatostatin clamp with infusions of insulin and low-dose followed by high-dose glucagon. We measured plasma levels of 17 AAs and assessed hepatic fat content (FF%) and body fat distribution (visceral and subcutaneous adipose tissue mass) by MRI. HighGlucagon suppressed plasma total AA equally in all groups; MASH 13% (SD 9%), MAS 14% (7%), CON 11% (5%), respectively. In univariate regression analyses visceral adipose tissue mass (ß = 0.471, P = 0.011) and AA concentration at LowGlucagon (ß = ─0.524, P = 0.004), but not FF% (ß = ─0.243, P = 0.213), were significant predictors of AA reduction. Using a stepwise backward multiple regression approach revealed similar results. Total and specific AA levels (glutamic acid, tyrosine) were higher in both MASLD groups during the study and FF% was positively correlated to a number of individual AAs. Though finding elevated AA concentrations in subjects with MASLD, we conclude that in MASLD patients that do not have elevated glucagon at baseline, glucagon suppresses circulating AA levels equally in subjects with and without MASLD. NCT04042142.

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Several recent studies have attempted to understand how fasting has benefits for body health, especially the nervous system. To evaluate the impact of intermittent fasting on body weight, brain neurotransmitters, brain oxidative stress, and brain-derived neurotrophic factor (BDNF) in several areas of the brain, this study was conducted in rats. Thirty male Wistar rats were randomly divided into two groups. Group 1 (15 rats) served as the control and group 2 (15 rats) underwent intermittent fasting (IF; 24 h) for 1, 7, or 15 days. The findings demonstrated that intermittent fasting significantly reduced body weight. In this sense, brain monoamines and amino acids, namely dopamine, glutamate, aspartate, and oxidative stress markers (malondialdehyde and nitric oxide), decreased significantly after 1 day of IF. However, norepinephrine, serotonin, gamma-amino butyric acid, and glycine increased significantly. Additionally, glutathione levels were markedly elevated in IF. Surprisingly, the neuromodulatory effect of intermittent fasting fluctuates depending on the IF period. To support this fluctuation, BDNF levels increased after 1 day in the hippocampus and decreased after 15 days of intermittent fasting in all areas of the brain tested. In conclusion, our results show that intermittent fasting has beneficial influences on the brain; however, prolonged intermittent fasting can also induce some unfavorable physiological outcomes that prevent optimal neurological function.

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BACKGROUND: Understanding the multifactorial nature of major depressive disorder (MDD) is crucial for tailoring treatments. However, the complex interplay of various factors underlying the development and progression of MDD poses significant challenges. Our previous study demonstrated improvements in cognitive functions in MDD patients undergoing treatment with selective serotonin reuptake inhibitors (SSRIs) supplemented with Lactobacillus plantarum 299v (LP299v). METHODS: To elucidate the biochemical mechanisms underlying cognitive functions improvements, we explored underlying metabolic changes. We employed multi-platform metabolomics, including LC-QTOF-MS and CE-TOF-MS profiling, alongside chiral LC-QqQ-MS analysis for amino acids. RESULTS: Supplementation of SSRI treatment with LP299v intensified the reduction of long-chain acylcarnitines, potentially indicating improved mitochondrial function. LP299v supplementation reduced N-acyl taurines more than four times compared to the placebo, suggesting a substantial impact on restoring biochemical balance. The LP299v-supplemented group showed increased levels of oxidized glycerophosphocholine (oxPC). Additionally, LP299v supplementation led to higher levels of sphingomyelins, L-histidine, D-valine, and p-cresol. LIMITATIONS: This exploratory study suggests potential metabolic pathways influenced by LP299v supplementation. However, the need for further research hinders the ability to draw definitive conclusions. CONCLUSIONS: Observed metabolic changes were linked to mitochondrial dysfunction, inflammation, oxidative stress, and gut microbiota disruption. Despite the subtle nature of this alterations, our research successfully detected these differences and connected them to the metabolic disruptions associated with MDD. Our findings emphasise the intricate relationship between metabolism, gut microbiota, and mental health prompting further research into the mechanisms of action of probiotics in MDD treatment.

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The Laptev Sea (LS) and Western East Siberian Sea (W-ESS) are paradigmatic examples of seas dominated by terrestrial organic matter, attributed to substantial Siberian River discharges and coastal erosion. The influx of terrestrial organic matter significantly alters the biochemical composition of particulate organic matter (POM) in these Arctic coastal regions, potentially reducing the nutritional quality available to higher trophic levels. This study investigated the origin and qualitative characteristics of POM in the LS and W-ESS during the late summer of 2018 by analyzing elemental ratios (C/N ratio), stable carbon isotopes (δ13C), and biochemical compositions (biomolecular and amino acid (AA) compositions). The conspicuously depleted δ13C values (mean ± standard deviation (SD) = -30.2 ± 0.5 ‰) and alongside elevated molar C/N ratios (mean ± SD = 18.1 ± 6.2) suggest that terrestrial organic matter is the predominant source of POM in the study area. Although carbohydrates (CHO) were the dominant biomolecules, their prevalence was higher in the river-influenced W-ESS region (67.7 ± 6.6 %) than in the LS region (58.6 ± 13.9 %; p < 0.05). Furthermore, the CHO composition was closely associated with freshwater content and river fraction, suggesting that the heightened contribution of CHO may stem from terrestrial organic matter delivered by river inputs. Lower concentrations of particulate hydrolyzable AA (PAA) and carbon and nitrogen normalized yields of AAs (AA-POC% and AA-PON%) along with reduced contribution of glycine suggested a substantial contribution of terrestrial POM to both LS and W-ESS POM. Overall, this study provides valuable insights into the terrestrial influence on POM composition in Arctic marine ecosystems, emphasizing the need for continued monitoring of the consequences of terrestrial carbon inputs in the changing Arctic environment.

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In this study, the performance of a novel organic tea compost developed for the first time in the world from raw tea waste from tea processing factories and enriched with worms, beneficial microorganisms, and enzymes was tested in comparison to chemical fertilizers in tea plantations in Rize and Artvin provinces, where the most intensive tea cultivation is carried out in Turkey. In the field trials, the developed organic tea vermicompost was incorporated into the root zones of the plants in the tea plantations in amounts of 1000 (OVT1), 2000 (OVT2) and 4000 (OVT4) (kg ha-1). The experimental design included a control group without OVT applications and positive controls with chemical fertilizers (N: P: K 25:5:10, (CF) 1200 kg ha-1) commonly used by local growers. The evaluation included field trials over two years. The average yields obtained in two-year field trials in five different areas were: Control (6326), OVT1 (7082), OVT2 (7408), OVT4 (7910), and CF (8028) kg ha-1. Notably, there was no significant statistical difference in yields between the organic (at 4000 kg ha-1 ) and chemical fertilizers (at 1200 kg ha-1). The highest nutrient contents were obtained when CF and OVT4 were applied. According to the average values across all regions, the application of OVT4 increased the uptake of 63% N, 18% K, 75% P, 21% Mg, 19% Na, 29% Ca, 28% Zn, 11% Cu and 24% Mn compared to the control group. The application of chemical fertilizers increased the uptake of 75% N, 21% K, 75% P, 21% Mg, 28% Na, 27% Ca, 30% Zn, 18% Cu and 31% Mn compared to the control group. The organic fertilizer treatment had the lowest levels of antioxidants compared to the control groups and the chemical fertilizers. It was also found that the organic fertilizer increased the levels of amino acids, organic acids and chlorophyll in the tea plant. Its low antioxidant activity and proline content prepared them for or protected them from stress conditions. With these properties, the biotechnologically developed organic tea compost fertilizer has proven to be very promising for tea cultivation and organic plant production.

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Amino acid scores have become very popular protein quality scores since their definition and recommendation by FAO expert groups. The chemical score is the central pillar of this method, and has been refined with digestibility correction factors, such as protein digestibility for the PD-CAAS and amino acid digestibility for the DIAAS. Several elements need to be taken into account to properly determine these scores, not only from a methodological point of view but also in order to reconcile regulation, pragmatism, accuracy and also biological significance. This review offers a reminder of the main points raised in the FAO reports on protein and AA requirements in 1995 and 2007, and on protein quality in 1991 and 2013. It also highlights the factors that most impact score metrics, and in particular the choice of reference pattern and protein determination in the food. Lastly, the scores are compared, and versus another quality score based on the physiological response, the protein efficiency ratio.

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Deep-sea sediments harbor abundant microbial communities extending vertically up to ~2.5 km below the seafloor. Despite their prevalence, the reasons for their large community sizes and low energy fluxes remain unclear. Particularly, the reliance of fungi, the predominant eukaryotic group, on amino acids in these energy-limited, anaerobic conditions is poorly understood. We investigated the role of amino acids in the growth and development of the fungus Schizophyllum commune 20R-7-F01, isolated from anaerobic sub-seafloor sediments. The fungus efficiently used all amino acids as carbon sources, and some as nitrogen sources, with specific amino acids influencing sexual reproduction and fruit-body formation. Notably, amino acids with hydrocarbon chains or methyl groups appeared crucial for fruit-body production. The upregulation of genes, metabolites, and pathways related to amino acid metabolism in the fungus under anaerobic conditions underscores the significance of amino acids as energy and nutrient sources in such environments. Amino acids not only served as carbon/nitrogen sources but also contributed to fungal fruit-body formation under low oxygen conditions, vital for long-term fungal survival in the energy-limited deep biosphere. This study sheds light on the crucial role of amino acids in fungal growth and reproduction in energy-limited anaerobic conditions. IMPORTANCE: In the depths beneath the ocean floor, where darkness, anaerobic conditions, and energy scarcity prevail, life persists against all odds. This study illuminates the pivotal role of amino acids, the fundamental building blocks of life, as a vital energy for deep subseafloor fungi. Our research uncovers how these fungi not only rely on amino acids for survival but also utilize them to reproduce, forming fruit bodies in environments deprived of oxygen and energy. This revelation not only elucidates the mechanisms enabling fungal survival in extreme conditions but also hints at the essentiality of amino acids as nutrients for other deep-sea microbes. By unraveling these mysteries of the hidden biosphere, our study opens new frontiers in understanding the resilience and adaptation of life in the most inhospitable environments on our planet.

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There is an increasing concern about using limited high-quality protein sources in the aquafeed industry. The alternative solution to this problem is cost-effective plant proteins such as soybean meal (SBM). However, it is better to improve plant protein-containing diets through processing and supplemental amino acids. This study aimed to examine the effects of fermented soybean meal (FSBM) and supplemental methionine and lysine (ML) in diets on growth, digestibility, and body and amino acid composition in Beluga (Huso huso). Two basal diets (490 g fish meal Kg-1) of fish meal (FM) and fish meal with methionine and lysine (FM+ML) were replaced by 40%, 60% and 80% of FSBM and FSBM+ML (FM, FSBM40, FSBM60, FSBM80, FM+ML, FSBM40+ML, FSBM60+ML and FSBM80+ML; 444 g kg-1 crude protein and 19.77 MJ kg-1 gross energy). The diets were fed to triplicate groups of Beluga (394.6 ± 4.3 g) 3 times daily for 56 days. Results showed that Beluga fed 80% FSBM and FSBM+ML had lower growth and feed utilization. Moreover, Beluga fed FSBM+ML performed poorer than those fed FSBM (P < 0.05). No interactions between fermented SBM and ML were observed in apparent digestibility coefficients (ADC) and body proximate composition except for ADC of crude lipid. ADC in Beluga fed 80% were less than other diets. Substitution of FSBM and FSBM+ML in diets significantly reduced dry matter, ash and crude lipid; Crude lipid increased in groups fed FSBM+ML (P < 0.05). FSBM and FSBM+ML in 60% had higher and lower total amino acids in muscle and faeces (P < 0.05), respectively. Also, excreted total amino acids in faeces increased with ML (P < 0.05). Generally, in Beluga, FSBM-containing diets showed better effects on growth, feed utilization, whole-body lipid, and muscle and faecal amino acids than those with FSBM+ML. Fermented SBM could be replaced up to 60%.

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BACKGROUND: Parenteral nutrition (PN) without enteral nutrition (EN) leads to marked atrophy of gut-associated lymphoid tissue (GALT), causing mucosal defense failure in both the gut and the extraintestinal mucosal system. We evaluated the effects of beta-hydroxy-beta-methylbutyrate (HMB) on GALT and gut morphology in PN-fed mice. METHODS: Experiment 1: male Institute of Cancer Research mice were assigned to the Chow (n = 12), Control (standard PN: n = 10), or H600 and H2000 (PN containing 600 mg/kg or H2000 mg/kg body weight of Ca-HMB: n = 12 and 10, respectively) groups. After 5 days of dietary manipulation, all mice were killed and the whole small intestine was harvested. GALT lymphocyte cell numbers and phenotypes of Peyer patch (PP), intraepithelial space, and lamina propria lymphocytes were evaluated. Experiment 2: 47 mice (Chow: n = 12; Control: n = 14; H600: n = 11; and H2000: n = 10) were fed for 5 days as in experiment 1. Proliferation and apoptosis of gut immune cells and mucosa, and protein expressions (mammalian target of rapamycin [mTOR], caspase-3, and Bcl2) were evaluated in the small intestine. RESULTS: Compared with the Controls, the Chow and HMB groups showed significantly higher PP cell numbers, prevented gut mucosal atrophy, inhibited apoptosis of gut cells, and increased their proliferation in association with increased mTOR activity and Bcl2 expression. CONCLUSION: HMB-supplemented PN is a potentially novel method of preserving GALT mass and gut morphology in the absence of EN.

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BACKGROUND: Skin aging research often focuses on the dermis, overlooking the significance of the retinacular cutis (RC) in aging. This study aimed to investigate the efficacy, safety, and effect of an injectable solution containing hyaluronic acid, amino acids, and peptides, on facial sagging and laxity by targeting the RC. METHODS: This single-center observational study recruited 28 female volunteers aged 25-65 years. The participants received four monthly injections of the studied solution. Objective measures included skin hydration, elasticity, color, thickness, collagen density evaluated via DermaLab Combo and high-resolution ultrasound imaging. Subjective measures included participant satisfaction evaluated using the Global Aesthetic Improvement Scale (GAIS). Adverse effects were monitored throughout the study period. RESULTS: Significant improvements were observed in skin hydration, elasticity, and collagen density after treatment. Hydration increased by 25.9% at T1 (30 days after last session), sustaining a 15.9% increase at T2 (120 days after last session). Elasticity improved by 29.2% at T1 and 20.7% at T2. Collagen density increased by 20.27% at T1 and 16.71% at T2. Self-reported GAIS scores showed consistent increases. Adverse effects were minimal and included only transient ecchymosis and mild pain. CONCLUSION: Injections of the solution had a substantial hydrating effect, enhanced elasticity, and increased collagen density in the RC and dermis. Results persisted at the 120-day follow-up, indicating sustained benefits. Hence, this injectable solution may offer a safe and effective non-invasive treatment option for improving skin laxity and sagging, targeting the RC and other deep connective tissue such as retaining ligaments.

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Protein solubility prediction is useful for the careful selection of highly effective candidate proteins for drug development. In recombinant proteins synthesis, solubility prediction is valuable for optimizing key protein characteristics, including stability, functionality, and ease of purification. It contains valuable information about potential biomarkers or therapeutic targets and helps in early forecasting of neurodegenerative diseases, cancer, and cardiovascular disorders. Traditional wet-lab experimental protein solubility prediction approaches are error-prone, time-consuming, and costly. Researchers harnessed the competence of Artificial Intelligence approaches for replacing experimental approaches with computational predictors. These predictors inferred the solubility of proteins by analyzing amino acids distributions in raw protein sequences. There is still a lot of room for the development of robust computational predictors because existing predictors remain fail in extracting comprehensive discriminative distribution of amino acids. To more precisely discriminate soluble proteins from insoluble proteins, this paper presents ProSol-Multi predictor that makes use of a novel MLCDE encoder and Random Forest classifier. MLCDE encoder transforms protein sequences into informative statistical vectors by capturing amino acids multi-level correlation and discriminative distribution within raw protein sequences. The performance of proposed encoder is evaluated against 56 existing protein sequence encoding methods on a widely used protein solubility prediction benchmark dataset under two different experimental settings namely intrinsic and extrinsic. Intrinsic evaluation reveals that from all sequence encoders, proposed MLCDE encoder manages to generate non-overlapping clusters of soluble and insoluble classes. In extrinsic evaluation, 10 machine learning classifiers achieve better performance with proposed MLCDE encoder as compared to 56 existing protein sequence encoders. Moreover, across 4 public benchmark datasets, proposed ProSol-Multi predictor outshines 20 existing predictors by an average accuracy of 3%, MCC and AU-ROC of 2%. ProSol-Multi interactive web application is available at https://sds_genetic_analysis.opendfki.de/ProSol-Multi.

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Background: The interplay between colon adenocarcinoma (COAD) and branched-chain amino acid (BCAA) metabolism is not fully understood, presenting a crucial area for investigation. Methods: We developed a prognostic model based on BCAA metabolism using the least absolute shrinkage and selection operator (LASSO) regression algorithm. We employed qRT-PCR and Western blot analyses to examine NOTCH3 expression in COAD tissues versus adjacent non-cancerous tissues and various cell lines. We also investigated the impact of NOTCH3 on COAD cell proliferation, invasion, and migration through in vitro and in vivo experiments. Results: Our BCAA metabolism-related signature (BRS) distinguished between different immune features, tumor mutation burdens, responses to immunotherapy, and drug sensitivity among COAD patients. NOTCH3 was found to be overexpressed in COAD, promoting tumor growth as verified through various assays. The model effectively predicted COAD prognosis and patient responses to treatments, underscoring the potential of BCAA pathways as therapeutic targets. Conclusion: The BRS is instrumental in predicting the prognosis and therapeutic response in COAD, with NOTCH3 playing a significant role in the proliferation, invasion and migration of COAD. These findings suggest that targeting BCAA metabolism and NOTCH3 could advance COAD treatment strategies.

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BACKGROUND: Xianju wheat paste, a traditional condiment in Hubei Province, China, possesses nutritional value and a distinctive taste profile. Nevertheless, there remains a dearth of comprehensive comprehension regarding the intricate interplay between the microbial population and its nutritional profile in Xianju wheat paste. RESULTS: It was determined that Xianju wheat paste harbors predominant microbial genera such as Bacillus, Staphylococcus and Aspergillus. The findings from high-throughput sequencing analysis revealed the presence of 11 bacterial genera in Xianju wheat paste, with relative abundances exceeding 1%. These genera included Bacillus, Staphylococcus, Brevibacterium, Lactobacillus, Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium, Enterobacteriaceae, Pantoea, Brachybacterium, Klebsiella, Escherichia-Shigella and Ochrobactrum. Furthermore, six fungal genera were identified with relative abundances greater than 1%, specifically Aspergillus, Zygosaccharomyces, Cutaneotrichosporon, Candida, Millerozyma and Rhizopus. The correlation analysis indicated a significant impact of the microbial community and nutritional flavor on the second phase of fermentation in Xianju wheat paste. The predominant bacterium Bacillus in Xianju wheat paste facilitated the production of free amino acids, whereas Staphylococcus exhibited a negative correlation with free amino acid levels. The quantity of volatile compounds in Xianju wheat paste progressively increased during fermentation, with the presence of typical aroma compounds 4-vinyl-2-methoxyphenol significantly associated with Bacillus. This indicated Bacillus notably enhanced the production of aromatic substances. Furthermore, a strong correlation was observed between Staphylococcus and the 18 volatile organic compounds, highlighting their substantial contribution to these aroma compounds. CONCLUSION: This research indicates that the presence of microbial communities significantly contributes to the development of the nutritional flavor profile in Xianju wheat paste. © 2024 Society of Chemical Industry.

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Kainoid natural products are a series of potent ionotropic glutamate receptor agonists produced by a variety of divergent marine micro- and macro-algae. The key biosynthetic step in the construction of the pyrrolidine ring pharmacophore involves a unique branch of non-heme iron α-ketoglutarate dependent dioxygenases (Fe/αKGs) termed the kainoid synthases. These Fe/αKG homologs catalyze a stereoselective C-H abstraction followed by a radical carbon-carbon bond reaction to form the bioactive core on N-prenylated L-glutamic acid substrates. In this article, we describe the expression, purification, and biochemical characterization of four divergent kainoid synthases (DabC, RadC1, DsKabC, GfKabC). Furthermore, we compare and contrast their substrate preferences and product distributions, and provide some preliminary insight into how to repurpose these enzymes for whole cell biocatalysis.

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A rationally designed dual purpose non-canonical amino acid (Trz) has been synthesised and successfully incorporated into a protein scaffold via genetic code expansion. Trz contains a 5-pyridyl-1,2,4-triazine system, which allows for inverse electron-demand Diels-Alder (IEDDA) reactions to occur on the triazine ring and for metal ions to be chelated both before and after the click reaction. Trz was successfully incorporated into a protein scaffold and the IEDDA utility of Trz demonstrated through the site-specific labelling of the purified protein with a bicyclononyne. Additionally, Trz was shown to successfully coordinate a cyclometallated iridium(III) centre, providing access to a bioorthogonal luminogenic probe. The luminescent properties of the Ir(III)-bound protein blue-shift upon IEDDA click reaction with bicyclononyne, providing a unique method for monitoring the extent and location of the labelling reaction. In summary, Trz is a new dual purpose non-canonical amino acid, which has great potential for myriad bioapplications where metal-based functionality is required, for example in imaging, catalysis, or photo-dynamic therapy, in conjunction with a bioorthogonal reactive handle to impart additional functionalities, such as dual modality imaging or therapeutic payloads.

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Nutritional programming is a promising concept for promoting metabolic adaptation of fish to challenging conditions, such as the increase in water temperature. The present work evaluates in ovo arginine or glutamine supplementation as enhancers of zebrafish metabolic or absorptive capacity, respectively, at optimum (28 ºC) and challenging temperatures (32 ºC) in the long-term. Growth performance, free amino acids profile, methylation index and the activity levels of digestive and intermediary metabolism enzymes were analysed to assess the metabolic plasticity induced by an early nutritional intervention. Temperature affected fish larvae growth performance. At the end of the experimental period 28 ºC-fish showed higher dry weight than 32 ºC-fish. The effects of the early supplementation were reflected in the larval free amino acids profile at the end of the experiment. Higher methylation potential was observed in the ARG-fish. In ovo amino acid supplementation modulated the metabolic response in zebrafish larvae, however, the magnitude of this effect differed according to the amino acid and the temperature. Overall, arginine supplementation enhanced carbohydrates metabolism at 32 ºC. In conclusion, the present work suggests that in ovo arginine supplementation may promote a better adaptive response to higher temperatures.