Arginine Biosynthesis Research Articles

A mitochondrial NAD/NADH kinase governs fungal virulence through an oxidative stress response and arginine biosynthesis in Fusarium graminearum

NADP/NADPH plays an indispensable role in cellular metabolism, serving as a pivotal cofactor in numerous enzymatic processes involved in anabolic pathways, antioxidant defense, and the biosynthesis of essential cellular components. NAD/NADH kinases (NADKs) phosphorylate NAD/NADH, constituting the sole de novo synthetic pathway for NADP/NADPH generation. Despite the pivotal role of NADP/NADPH in cellular functions, the physiological role of NADK remains largely unexplored in filamentous fungi. In this study, we identified three putative NADKs in Fusarium graminearum—FgNadk1, FgNadk2, and FgNadk3—responsible for NAD/NADH phosphorylation. NADK-mediated formation of intracellular NADPH proved crucial for vegetative growth, sexual reproduction, and virulence. Specifically, FgNadk2, the mitochondrial NADK, played a role in oxidative stress resistance and the maintenance of mitochondrial reactive oxygen species levels. Moreover, the deletion of FgNADK2 resulted in arginine auxotrophy, contributing to the reduced fungal virulence. These findings underscore the necessity of mitochondrial NADK in fungal virulence in F. graminearum, revealing its involvement in mitochondrial redox homeostasis and the arginine biosynthetic pathway. This study provides critical insights into the interconnectedness of metabolic pathways essential for fungal growth, stress response, and pathogenicity.

Arginine inhibits the arginine biosynthesis rate-limiting enzyme and leads to the accumulation of intracellular aspartate in Synechocystis sp. PCC 6803

Cyanobacteria are oxygen-evolving photosynthetic prokaryotes that affect the global carbon and nitrogen turnover. Synechocystis sp. PCC 6803 (Synechocystis 6803) is a model cyanobacterium that has been widely studied and can utilize and uptake various nitrogen sources and amino acids from the outer environment and media. l-arginine is a nitrogen-rich amino acid used as a nitrogen reservoir in Synechocystis 6803, and its biosynthesis is strictly regulated by feedback inhibition. Argininosuccinate synthetase (ArgG; EC 6.3.4.5) is the rate-limiting enzyme in arginine biosynthesis and catalyzes the condensation of citrulline and aspartate using ATP to produce argininosuccinate, which is converted to l-arginine and fumarate through argininosuccinate lyase (ArgH). We performed a biochemical analysis of Synechocystis 6803 ArgG (SyArgG) and obtained a Synechocystis 6803 mutant overexpressing SyArgG and ArgH of Synechocystis 6803 (SyArgH). The specific activity of SyArgG was lower than that of other arginine biosynthesis enzymes and SyArgG was inhibited by arginine, especially among amino acids and organic acids. Both arginine biosynthesis enzyme-overexpressing strains grew faster than the wild-type Synechocystis 6803. Based on previous reports and our results, we suggest that SyArgG is the rate-limiting enzyme in the arginine biosynthesis pathway in cyanobacteria and that arginine biosynthesis enzymes are similarly regulated by arginine in this cyanobacterium. Our results contribute to elucidating the regulation of arginine biosynthesis during nitrogen metabolism.

Postharvest quality and metabolism changes of daylily flower buds treated with hydrogen sulfide during storage

Daylily flower buds are a good source of nutrients and contain lots of bioactive compounds, but they are subject to deterioration after harvest, which limits the taste and consumer satisfaction. Hydrogen sulfide (H2S) has been regarded as an important gaseous signaling molecule, which could prolong postharvest freshness of fruits and vegetables. The present study aims to investigate the effects of H2S on postharvest quality and metabolism changes of daylily flower buds during storage. The results showed that 3.2 mM NaHS (H2S donor) effectively inhibited weight loss, blooming and decay of daylily during storage. H2S application markedly reduced the accumulation of malondialdehyde and H2O2. H2S treatment also delayed the loss of total protein and antioxidant glutathione, and maintained the activities of antioxidant enzymes superoxide dismutase and catalase at higher level compared to control group. Widely targeted metabolomics identified various differentially accumulated metabolites (DAMs) during storage and with H2S treatment of daylily. These DAMs largely distributed in the classes of amino acids, organic acids, sugars and alcohols, terpenoids. A special focus was given to 303 common DAMs between the comparison of CK0 vs. CK6 and CK6 vs. T6, of which the DAMs were mainly enriched in the KEGG pathways of monobactam biosynthesis, pyrimidine metabolism, glycine, serine and threonine metabolism, arginine biosynthesis, pentose and glucuronate interconversions. Four DAMs including Cytidine 5′-Monophosphate, Fumaric Acid, Hydroxypyruvic Acid, 2′-Deoxycytidine-5′-Monophosphoric Acid exhibited great downregulation during storage, and H2S treatment dramatically recovered their relative contents. This study indicated that H2S treatment offers the potential to preserve the quality of daylily flower buds and extend their postharvest life.

Tangshen Formula alleviates inflammatory injury against aged diabetic kidney disease through modulating gut microbiota composition and related amino acid metabolism

Diabetic kidney disease (DKD) is leading causes and one of the fastest growing causes of chronic kidney disease worldwide, and leads to high morbidity and mortality. Emerging evidences have revealed gut microbiota dysbiosis and related metabolism dysfunction play a dominant role in DKD progression and treatment through modulating inflammation. Our previous studies showed that Tangshen Formula (TSF), a Chinese herbal prescription, exhibited anti-inflammatory effect on DKD, but underlying mechanism that involved gut microbiota and related metabolism in aged model remained obscure. Here, BTBR ob/ob mice were used to establish aged DKD model, and 16S rRNA sequence and untargeted metabolomic analyses were employed to investigate the correlation between colonic microbiota and serum metabolism. The aged ob/ob mice exhibited obvious glomerular and renal tubule injury and kidney function decline in kidney, while TSF treatment significantly attenuated these abnormalities. TSF also exhibited potent anti-inflammatory effect in aged ob/ob mice indicating by reduced proinflammatory factor IL-6 and TNF-α, MCP-1 and COX-2 in serum, kidney and intestine, which suggested the involvement of gut microbiota with TSF effect. The 16S rDNA sequencing of the colonic microbiome and untargeted serum metabolomics analysis revealed significant differences in gut microbiota structure and serum metabolomic profiles between WT and ob/ob mice. Notably, TSF treatment reshaped the structure of gut microbiota and corrected the disorder of metabolism especially tryptophan metabolism and arginine biosynthesis. TSF increased Anaeroplasma and Barnesiella genera and decreased Romboutsia, Akkermansia, and Collinsella genera, and further elevated tryptophan, 5-hydroxyindoleacetate, glutamic acid, aspartate and reduced 4-hydroxy-2-quinolinecarboxylic acid, indole-3-acetic acid, xanthurenic acid, glutamine. Further correlation analysis indicated that disturbed gut microbiota was linked to tryptophan metabolism and arginine biosynthesis to regulate inflammation in aged DKD. Our data revealed that TSF attenuated renal inflammation by modulating gut microbiota and related amino acid metabolism in aged DKD model, highlighting gut microbiota and related metabolism functioned as potential therapeutic target for DKD in elderly patients.

Regulation of Sacha Inchi protein on fecal metabolism and intestinal microorganisms in mice.

With the increasing demand for protein utilization, exploring new protein resources has become a research hotspot. Sacha Inchi Protein (SIP) is a high-quality plant protein extracted from Sacha Inchi meal. This study aimed to investigate the impact of SIP on mouse metabolomics and gut microbiota diversity and explore the underlying pathways responsible for its health benefits. In this study, the structural composition of SIP was investigated, and the effects of SIP on fecal metabolomics and intestinal microorganisms in mice were explored by LC-MS metabolomics technology analysis and 16S rRNA gene sequencing. The results showed that SIP was rich in amino acids, with the highest Manuscript Click here to view linked References content of arginine, which accounted for 22.98% of the total amino acid content; the potential fecal metabolites of mice in the SIP group involved lipid metabolism, sphingolipid metabolism, arginine biosynthesis, and amino acid metabolism; SIP altered the microbial composition of the cecum in mice, decreased the Firmicutes/Bacteroidetes value, and It decreased the abundance of the harmful intestinal bacteria Actinobacteriota and Desulfobacterota, and increased the abundance of the beneficial intestinal bacteria Faecalibaculum, Dubosiella. In conclusion, SIP is a high-quality plant protein with great potential for development in lipid-lowering, intestinal health, and mental illness, providing valuable clues for further research on its health-promoting mechanisms.

Codonopsis pilosula water extract delays D-galactose-induced aging of the brain in mice by activating autophagy and regulating metabolism

Ethnopharmacological relevanceCodonopsis pilosula (C. pilosula), also called “Dangshen” in Chinese, is derived from the roots of Codonopsis pilosula (Franch.) Nannf. (C. pilosula), Codonopsis pilosula var. Modesta (Nannf.) L.D.Shen (C. pilosula var. modesta) or Codonopsis pilosula subsp. Tangshen (Oliv.) D.Y.Hong (C. pilosula subsp. tangshen), is a well-known traditional Chinese medicine. It has been regularly used for anti-aging, strengthening the spleen and tonifying the lungs, regulating blood sugar, lowering blood pressure, strengthening the body's immune system, etc. However, the mechanism, by which, C. pilosula exerts its therapeutic effects on brain aging remains unclear. Aim of the studyThis study aimed to investigate the underlying mechanisms of the protective effects of C. pilosula water extract (CPWE) on the hippocampal tissue of D-galactose-induced aging mice. Materials and methodsIn this research, plant taxonomy has been confirmed in the “The Plant List” database (www.theplantlist.org). First, an aging mouse model was established through the intraperitoneal injections of D-galactose solution, and low-, medium-, and high-dose CPWE were administered to mice by gavage for 42 days. Then, the learning and memory abilities of the mice were examined using the Morris water maze tests and step-down test. Hematoxylin and eosin staining was performed to visualize histopathological damage in the hippocampus. A transmission electron microscope was used to observe the ultrastructure of hippocampal neurons. Immunohistochemical staining was performed to examine the expression of glial fibrillary acidic protein (GFAP), the marker protein of astrocyte activation, and autophagy-related proteins, including microtubule-associated protein light chain 3 (LC3) and sequestosome 1 (SQSTM1)/p62, in the hippocampal tissues of mice. Moreover, targeted metabolomic analysis was performed to assess the changes in polar metabolites and short-chain fatty acids in the hippocampus. ResultsFirst, CPWE alleviated cognitive impairment and ameliorated hippocampal tissue damage in aging mice. Furthermore, CPWE markedly alleviated mitochondrial damage, restored the number of autophagosomes, and activated autophagy in the hippocampal tissue of aging mice by increasing the expression of LC3 protein and reducing the expression of p62 protein. Meanwhile, the expression levels of the brain injury marker protein GFAP decreased. Moreover, quantitative targeted metabolomic analysis revealed that CPWE intervention reversed the abnormal levels of L-asparagine, L-glutamic acid, L-glutamine, serotonin hydrochloride, succinic acid, and acetic acid in the hippocampal tissue of aging mice. CPWE also significantly regulated pathways associated with D-glutamine and D-glutamate metabolism, nitrogen metabolism, arginine biosynthesis, alanine, aspartate, and glutamate metabolisms, and aminoacyl-tRNA biosynthesis. ConclusionsCPWE could improve cognitive and pathological conditions induced by D-galactose in aging mice by activating autophagy and regulating metabolism, thereby slowing down brain aging.

Effects of dietary chlorogenic acid on cecal microbiota and metabolites in broilers during lipopolysaccharide-induced immune stress.

The aim of this study was to investigate the effects of chlorogenic acid (CGA) on the intestinal microorganisms and metabolites in broilers during lipopolysaccharide (LPS)-induced immune stress. A total of 312 one-day-old Arbor Acres (AA) broilers were randomly allocated to four groups with six replicates per group and 13 broilers per replicate: (1) MS group (injected with saline and fed the basal diet); (2) ML group (injected with 0.5 mg LPS/kg and fed the basal diet); (3) MA group (injected with 0.5 mg LPS/kg and fed the basal diet supplemented with 1,000 mg/kg CGA); and (4) MB group (injected with saline and fed the basal diet supplemented with 1,000 mg/kg CGA). The results showed that the abundance of beneficial bacteria such as Bacteroidetes in the MB group was significantly higher than that in MS group, while the abundance of pathogenic bacteria such as Streptococcaceae was significantly decreased in the MB group. The addition of CGA significantly inhibited the increase of the abundance of harmful bacteria such as Streptococcaceae, Proteobacteria and Pseudomonas caused by LPS stress. The population of butyric acid-producing bacteria such as Lachnospiraceae and Coprococcus and beneficial bacteria such as Coriobacteriaceae in the MA group increased significantly. Non-targeted metabonomic analysis showed that LPS stress significantly upregulated the 12-keto-tetrahydroleukotriene B4, riboflavin and mannitol. Indole-3-acetate, xanthurenic acid, L-formylkynurenine, pyrrole-2-carboxylic acid and L-glutamic acid were significantly down-regulated, indicating that LPS activated inflammation and oxidation in broilers, resulting in intestinal barrier damage. The addition of CGA to the diet of LPS-stimulated broilers significantly decreased 12-keto-tetrahydro-leukotriene B4 and leukotriene F4 in arachidonic acid metabolism and riboflavin and mannitol in ABC transporters, and significantly increased N-acetyl-L-glutamate 5-semialdehyde in the biosynthesis of amino acids and arginine, The presence of pyrrole-2-carboxylic acid in D-amino acid metabolism and the cecal metabolites, indolelactic acid, xanthurenic acid and L-kynurenine, indicated that CGA could reduce the inflammatory response induced by immune stress, enhance intestinal barrier function, and boost antioxidant capacity. We conclude that CGA can have a beneficial effect on broilers by positively altering the balance of intestinal microorganisms and their metabolites to inhibit intestinal inflammation and barrier damage caused by immune stress.

Effect of exogenous tannic acid on reduction of biogenic amines and citrinin in monascal soybean and metabolomics analysis

Biogenic amines (BAs) are often involved in human pathologies such as hypersensitivity symptoms. This research studied the effect of exogenous tannic acid (ETA) supplementation at various concentrations (0–20 mg/mL) on BA and mycotoxin citrinin levels in monascal soybean (MSB) and conducted a metabolomics analysis to estimate the metabolites in MSB. Addition of 20 mg/mL ETA decreased BA and citrinin levels in MSB after 25 days of fermentation by > 1.76 and >2.46 fold, respectively compared to the treatment without ETA addition. After 10 days of fermentation, the number of enterococci in MSB after treatment of >10 mg/mL ETA decreased by a minimum of 1.33 log CFU/g. ETA promoted large amounts of monacolin K, Monascus pigments, and free amino acids (FAAs) in MSB. A heatmap-HCA revealed that the 20 mg/mL ETA treatment was optimal, as confirmed by the VIP score and PCA. During MSB fermentation, seven notable metabolic pathways were identified as 1. phenylalanine metabolism, 2. arginine and proline metabolism, 3. phenylalanine, tyrosine, and tryptophan biosynthesis, 4. arginine biosynthesis, 5. histidine metabolism, 6. tryptophan metabolism, and 7. tyrosine metabolism. Supplementation of ETA in soybean substrate led to reduced BA and citrinin levels in MSB. The metabolomics analysis provide a better understanding of metabolite correlations, especially FAA formation and BA biosynthesis.

Rice-Magnaporthe oryzae interactions in resistant and susceptible rice cultivars under panicle blast infection based on defense-related enzyme activities and metabolomics.

Rice blast, caused by rice blast fungus (Magnaporthe oryzae), is a global threat to food security, with up to 50% yield losses. Panicle blast is a severe form of rice blast, and disease responses vary between cultivars with different genotypes. Reactive oxygen species (ROS)-mediated signaling reactions and the phenylpropanoid pathway are important defense mechanisms involved in recognizing and resisting against fungal infection. To understand rice-M. oryzae interactions in resistant and susceptible cultivars, we determined dynamic changes in the activities of five defense-related enzymes in resistant cultivar jingsui 18 and susceptible cultivar jinyuan 899 infected with M. oryzae from 4 to 25 days after infection. We then performed untargeted metabolomics analyses to profile the metabolomes of the cultivars under infected and non-infected conditions. Dynamic changes in the activities of five defense-related enzymes were closely related to panicle blast resistance in rice. Metabolome data analysis identified 634 differentially accumulated metabolites (DAMs) between resistant and susceptible cultivars following infection, potentially explaining differences in disease response between varieties. The most enriched DAMs were associated with lipids and lipid-like molecules, phenylpropanoids and polyketides, organoheterocyclic compounds, organic acids and derivatives, and lignans, neolignans, and related compounds. Multiple metabolic pathways are involved in resistance to panicle blast in rice, including biosynthesis of other secondary metabolites, amino acid metabolism, lipid metabolism, phenylpropanoid biosynthesis, arachidonic acid metabolism, arginine biosynthesis, tyrosine metabolism, tryptophan metabolism, tyrosine and tryptophan biosynthesis, lysine biosynthesis, and oxidative phosphorylation.

Using liquid chromatography and mass spectrometry to predict potential biomarkers for missed miscarriage and its metabolic pathways in a tertiary center: A cross-sectional analytic study.

To determine and compare the serum metabolites in missed abortion versus normal early pregnancy using ultra-high-performance liquid chromatography and tandem time-of-flight mass spectrometry, and to determine how these metabolites can be used to predict the potential biomarkers and possible metabolic pathways of a missed abortion. The serum of patients with a missed abortion was used as the experimental group and the serum of patients with an induced abortion during normal early pregnancy was used as the control group. Principal component analysis and orthogonal partial least square discriminant analysis were additionally used to observe the difference in metabolite distribution between the two groups. A variable weight value (variable importance in the projection; VIP) obtained from the orthogonal partial least squares discriminant analysis model more than 1 and P less than 0.05 were taken to indicate significant differences in metabolite screening. After this, enrichment analysis of the metabolic pathways of these metabolites was conducted using Fisher precise test in order to find the metabolic pathway with the highest correlation with the differential metabolites. In total, 30 patients were included in the experimental group, with 30 patients in the control group. Fifty-five metabolites (VIP > 1, P < 0.05) with significant differences related to missed abortion were selected, among which 35 metabolites increased and 20 decreased in patients with a missed abortion. KEGG pathway enrichment analysis showed that the four metabolic pathways with the highest correlation were cholesterol metabolism, arginine biosynthesis, cell apoptosis, and the FoxO signaling pathway. The missed abortion serum metabolites and changes in related metabolic pathways reported in this study provide a basis for the early prediction and diagnosis of a missed abortion.

Analyses of plasma metabolites using a high performance four-channel CIL LC-MS method and identification of metabolites associated with enteric methane emissions in beef cattle.

Reducing enteric methane (one greenhouse gas) emissions from beef cattle not only can be beneficial in reducing global warming, but also improve efficiency of nutrient utilization in the production system. However, direct measurement of enteric methane emissions on individual cattle is difficult and expensive. The objective of this study was to detect plasma metabolites that are associated with enteric methane emissions in beef cattle. Average enteric methane emissions (CH4) per day (AVG_DAILYCH4) for each individual cattle were measured using the GreenFeed emission monitoring (GEM) unit system, and beef cattle with divergent AVG_DAILYCH4 from Angus (n = 10 for the low CH4 group and 9 for the high CH4 group), Charolais (n = 10 for low and 10 for = high), and Kinsella Composite (n = 10 for low and 10 for high) populations were used for plasma metabolite quantification and metabolite-CH4 association analyses. Blood samples of these cattle were collected near the end of the GEM system tests and a high performance four-channel chemical isotope labeling (CIL) liquid chromatography (LC) mass spectrometer (MS) method was applied to identify and quantify concentrations of metabolites. The four-channel CIL LC-MS method detected 4235 metabolites, of which 1105 were found to be significantly associated with AVG_DAILYCH4 by a t-test, while 1305 were significantly associated with AVG_DAILYCH4 by a regression analysis at p<0.05. Both the results of the t-test and regression analysis revealed that metabolites that were associated with enteric methane emissions in beef cattle were largely breed-specific whereas 4.29% to 6.39% CH4 associated metabolites were common across the three breed populations and 11.07% to 19.08% were common between two breed populations. Pathway analyses of the CH4 associated metabolites identified top enriched molecular processes for each breed population, including arginine and proline metabolism, arginine biosynthesis, butanoate metabolism, and glutathione metabolism for Angus; beta-alanine metabolism, pyruvate metabolism, glycolysis / gluconeogenesis, and citrate cycle (TCA cycle) for Charolais; phenylalanine, tyrosine and tryptophan biosynthesis, phenylalanine metabolism, arginine biosynthesis, and arginine and proline metabolism for Kinsella Composite. The detected CH4 associated metabolites and enriched molecular processes will help understand biological mechanisms of enteric methane emissions in beef cattle. The detected CH4 associated plasma metabolites will also provide valuable resources to further characterize the metabolites and verify their utility as biomarkers for selection of cattle with reduced methane emissions.

Molecular Mechanisms of Growth Differences in Gymnocypris przewalskii and Gymnocypris eckloni through a Comparative Transcriptome Perspective

Genetic composition plays a crucial role in the growth rate of species, and transcriptomics provides a potent tool for studying genetic aspects of growth. We explored the growth rates and transcriptomes of the Cyprinids G. przewalskii (GP) and G. eckloni (GE). A total of 500 individuals of G. przewalskii and G. eckloni, matched in size, were separately cultured for 9 months in six cement tanks (each group with three replicates). Growth indices were measured, revealing that the growth rate of GE was greater than that of GP (p &lt; 0.05), while there was no significant difference in survival rates (p &gt; 0.05). Simultaneously, we conducted RNA-Seq on the muscles of both GP and GE. The results indicated a significant difference of gene expression between GP and GE, identifying 5574 differentially expressed genes (DEGs). Quantitative real-time reverse transcription–polymerase chain reaction of 10 DEGs demonstrated consistency in expression profiles with the results from the RNA-Seq analysis. The DEGs were significantly enriched in glycolysis/gluconeogenesis (ko00010), arachidonic acid formation (ko00061), arginine biosynthesis (ko00220), and the MAPK (ko04013), PI3K-Akt (ko04151), mTOR (ko04150), and TGF-β (ko04350) signal pathways, as revealed by Gene Ontology (GO) enrichment and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. This study also identified some growth-related DEGs, such as IGF2, Noggin, Decorin and others. Notably, the low expression of IGF2 may be a factor contributing to the slower growth of GP than GE.

Screening potential biomarkers associated with insulin resistance in high-fat diet-fed mice by integrating metagenomics and untargeted metabolomics.

In this study, we aim to identify the microbes and metabolites linked to insulin resistance, some of which have not been previously reported in insulin resistance-related studies. This adds a complementary dimension to existing research. Furthermore, we establish a correlation between alterations in the gut microbiota and metabolite levels. These findings serve as a foundation for identifying the causal bacterial species and metabolites. They also offer insights that guide further exploration into the mechanisms through which these factors influence host insulin resistance.

Dendropanax morbifera Leveille Extract-Induced Alteration of Metabolic Profile in Whitening Effects

This study aimed to evaluate the potential of Dendropanax morbifera Leveille (D. morbifera) extract as a natural melanin depigmentation agent to achieve skin whitening. Treating α-MSH-stimulated B16-F10 cells with the extract effectively inhibited melanin production and tyrosinase activity. The cellular metabolic profiles were analyzed to understand the mechanisms underlying the whitening-related metabolic processes. We identified 29 metabolites that were significantly altered in the α-MSH-stimulated B16-F10 cells. The melanin-synthesis-related pathways that were downregulated included phenylalanine, tyrosine, and tryptophan biosynthesis and phenylalanine metabolism. Simultaneously, alanine, aspartate, and glutamate metabolism; arginine and proline metabolism; arginine biosynthesis; butanoate metabolism; glutathione metabolism; and glyoxylate and dicarboxylate metabolism were upregulated. We found that the optimal extract concentration of 0.2 mg/mL showed the highest efficacy in reversing the alterations to the metabolite levels and metabolic pathways. Moreover, D. morbifera extract exerted low cytotoxicity and high efficacy in inhibiting melanin production. Thus, D. morbifera extract is a potential melanin inhibitor with application in the development of whitening cosmetics.

Untargeted Metabolomics Based on UPLC-Q-Exactive-Orbitrap-MS/MS Revealed the Differences and Correlations between Different Parts of the Root of Paeonia lactiflora Pall.

Paeonia lactiflora Pall. (PLP) is a plant with excellent ornamental and therapeutic value that can be utilized in traditional Chinese medicine as Paeoniae Radix Alba (PRA) and Paeoniae Radix Rubra (PRR). PRA must undergo the "peeling" process, which involves removing the cork and a portion of the phloem. PLP's biological function is strongly linked to its secondary metabolites, and the distribution of metabolites in different regions of the PLP rhizome causes changes in efficacy when PLP is processed into various therapeutic compounds. The metabolites of the cork (cor), phloem (phl), and xylem (xyl) were examined in the roots of PLP using a metabolomics approach based on UPLC-Q-Exactive-Orbitrap-MS/MS (UPLC-MS/MS), and the differential metabolites were evaluated using multivariate analysis. Significant changes were observed among the cor, phl, and xyl samples. In both positive and negative ion modes, a total of 15,429 peaks were detected and 7366 metabolites were identified. A total of 525 cor-phl differential metabolites, 452 cor-xyl differential metabolites, and 328 phl-xyl differential metabolites were evaluated. Flavonoids, monoterpene glycosides, fatty acids, sugar derivatives, and carbohydrates were among the top 50 dissimilar chemicals. The key divergent metabolic pathways include linoleic acid metabolism, galactose metabolism, ABC transporters, arginine biosynthesis, and flavonoid biosynthesis. The cor, phl, and xyl of PLP roots exhibit significantly different metabolite types and metabolic pathways; therefore, "peeling" may impact the pharmaceutical effect of PLP. This study represents the first metabolomics analysis of the PLP rhizome, laying the groundwork for the isolation and identification of PLP pharmacological activity, as well as the quality evaluation and efficacy exploration of PLP.

Plasma metabolomic differences in early-onset compared to average-onset colorectal cancer

Deleterious effects of environmental exposures may contribute to the rising incidence of early-onset colorectal cancer (eoCRC). We assessed the metabolomic differences between patients with eoCRC, average-onset CRC (aoCRC), and non-CRC controls, to understand pathogenic mechanisms. Patients with stage I–IV CRC and non-CRC controls were categorized based on age ≤ 50 years (eoCRC or young non-CRC controls) or ≥ 60 years (aoCRC or older non-CRC controls). Differential metabolite abundance and metabolic pathway analyses were performed on plasma samples. Multivariate Cox proportional hazards modeling was used for survival analyses. All P values were adjusted for multiple testing (false discovery rate, FDR P < 0.15 considered significant). The study population comprised 170 patients with CRC (66 eoCRC and 104 aoCRC) and 49 non-CRC controls (34 young and 15 older). Citrate was differentially abundant in aoCRC vs. eoCRC in adjusted analysis (Odds Ratio = 21.8, FDR P = 0.04). Metabolic pathways altered in patients with aoCRC versus eoCRC included arginine biosynthesis, FDR P = 0.02; glyoxylate and dicarboxylate metabolism, FDR P = 0.005; citrate cycle, FDR P = 0.04; alanine, aspartate, and glutamate metabolism, FDR P = 0.01; glycine, serine, and threonine metabolism, FDR P = 0.14; and amino-acid t-RNA biosynthesis, FDR P = 0.01. 4-hydroxyhippuric acid was significantly associated with overall survival in all patients with CRC (Hazards ratio, HR = 0.4, 95% CI 0.3–0.7, FDR P = 0.05). We identified several unique metabolic alterations, particularly the significant differential abundance of citrate in aoCRC versus eoCRC. Arginine biosynthesis was the most enriched by the differentially altered metabolites. The findings hold promise in developing strategies for early detection and novel therapies.

Short-chain fatty acids in breast milk and their relationship with the infant gut microbiota.

The short-chain fatty acids (SCFAs) contained in breast milk play a key role in infant growth, affecting metabolism and enhancing intestinal immunity by regulating inflammation. In order to examine the associations between the microbiota and SCFA levels in breast milk, and explore the roles of SCFAs in regulating the infant gut microbiota, we enrolled 50 paired mothers and infants and collected both breast milk and infant fecal samples. Breast milk SCFA contents were determined by UPLC-MS, and whole genome shotgun sequencing was applied to determine the microbial composition of breast milk and infant feces. The SCFA levels in breast milk were grouped into tertiles as high, medium, or low, and the differences of intestinal microbiota and KEGG pathways were compared among groups. The results demonstrated that breast milk butyric acid (C4) is significantly associated with Clostridium leptum richness in breastmilk. Additionally, the specific Bifidobacterium may have an interactive symbiosis with the main species of C4-producing bacteria in human milk. Women with a low breast milk C4 tertile are associated with a high abundance of Salmonella and Salmonella enterica in their infants' feces. KEGG pathway analysis further showed that the content of C4 in breast milk is significantly correlated with the infants' metabolic pathways of lysine and arginine biosynthesis. This study suggests that interactive symbiosis of the microbiota exists in breast milk. Certain breast milk microbes could be beneficial by producing C4 and further influence the abundance of certain gut microbes in infants, playing an important role in early immune and metabolic development.

Mechanistic insights into inositol-mediated rumen function promotion and metabolic alteration using in vitro and in vivo models.

Inositol is a bioactive factor that is widely found in nature; however, there are few studies on its use in ruminant nutrition. This study investigated the effects of different inositol doses and fermentation times on rumen fermentation and microbial diversity, as well as the levels of rumen and blood metabolites in sheep. Rumen fermentation parameters, microbial diversity, and metabolites after different inositol doses were determined in vitro. According to the in vitro results, six small-tailed Han sheep fitted with permanent rumen fistulas were used in a 3 × 3 Latin square feeding experiment where inositol was injected into the rumen twice a day and rumen fluid and blood samples were collected. The in vitro results showed that inositol could increase in vitro dry matter digestibility, in vitro crude protein digestibility, NH3-N, acetic acid, propionic acid, and rumen microbial diversity and affect rumen metabolic pathways (p < 0.05). The feeding experiment results showed that inositol increased the blood concentration of high-density lipoprotein and IgG, IgM, and IL-4 levels. The rumen microbial composition was significantly affected (p < 0.05). Differential metabolites in the rumen were mainly involved in ABC transporters, biotin metabolism, and phenylalanine metabolism, whereas those in the blood were mainly involved in arginine biosynthesis and glutathione and tyrosine metabolism. In conclusion, inositol improves rumen function, affects rumen microorganisms and rumen and blood metabolites and may reduce inflammation, improving animal health.

Effects of bifenthrin pesticide on fermented cultures and metabolite profiles of kombucha tea

Pesticide residue contamination in raw materials influences the quality of fermented products. This study investigated the effects of bifenthrin (1, 3, 5, and 30 mg/L) in tea broth on the composition and metabolite profiles of kombucha tea. Bifenthrin at 30 mg/L (B30) showed an adverse effect on kombucha composition, with reduced 0.63–1 log CFU/mL of each microbial group (acetic acid bacteria, lactic acid bacteria, and yeast), while lower concentrations of bifenthrin gave decreased 0.30–0.84 log CFU/mL of each fermented culture. The presence of bifenthrin altered the kombucha metabolites and instigated intervening microbial metabolisms, such as arginine biosynthesis and pyrimidine metabolism, which resulted in reduced production of amino acids, amino derivatives, organic acids, and other beneficial compounds. B30 addition also reduced flavonoid content and antioxidant activity of kombucha tea by 16% (0.143–0.223 mg quercetin/mL) and 5% (0.239–0.278 mg Trolox/mL), respectively. Findings demonstrated that the presence of bifenthrin decreased kombucha tea quality in terms of chemical composition and reduced beneficial microbial populations by disrupting their biological pathways.

Biological functions at high pressure: transcriptome response of Shewanella oneidensis MR-1 to hydrostatic pressure relevant to Titan and other icy ocean worlds.

High hydrostatic pressure (HHP) is a key driver of life's evolution and diversification on Earth. Icy moons such as Titan, Europa, and Enceladus harbor potentially habitable high-pressure environments within their subsurface oceans. Titan, in particular, is modeled to have subsurface ocean pressures ≥ 150 MPa, which are above the highest pressures known to support life on Earth in natural ecosystems. Piezophiles are organisms that grow optimally at pressures higher than atmospheric (0.1 MPa) pressure and have specialized adaptations to the physical constraints of high-pressure environments - up to ~110 MPa at Challenger Deep, the highest pressure deep-sea habitat explored. While non-piezophilic microorganisms have been shown to survive short exposures at Titan relevant pressures, the mechanisms of their survival under such conditions remain largely unelucidated. To better understand these mechanisms, we have conducted a study of gene expression for Shewanella oneidensis MR-1 using a high-pressure experimental culturing system. MR-1 was subjected to short-term (15 min) and long-term (2 h) HHP of 158 MPa, a value consistent with pressures expected near the top of Titan's subsurface ocean. We show that MR-1 is metabolically active in situ at HHP and is capable of viable growth following 2 h exposure to 158 MPa, with minimal pressure training beforehand. We further find that MR-1 regulates 264 genes in response to short-term HHP, the majority of which are upregulated. Adaptations include upregulation of the genes argA, argB, argC, and argF involved in arginine biosynthesis and regulation of genes involved in membrane reconfiguration. MR-1 also utilizes stress response adaptations common to other environmental extremes such as genes encoding for the cold-shock protein CspG and antioxidant defense related genes. This study suggests Titan's ocean pressures may not limit life, as microorganisms could employ adaptations akin to those demonstrated by terrestrial organisms.