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1.
Pestic Biochem Physiol ; 199: 105805, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38458670

RESUMO

Diquat (DQ) poisoning has garnered attention in recent years, primarily due to the rising incidence of cases worldwide, coupled with the absence of a viable antidote for its treatment. Despite the fact that diquat monopyridone (DQ-M) has been identified as a significant metabolite of DQ, the enzyme responsible for its formation remains unknown. In this study, we have identified aldehyde oxidase (AOX) as a vital enzyme involved in DQ oxidative metabolism. The metabolism of DQ to DQ-M was significantly inhibited by AOX inhibitors including raloxifene and hydralazine. The source of oxygen incorporated into DQ-M was proved to be from water through a H218O incubation experiment which further corroborated DQ-M formation via AOX metabolism. The product of DQ-M in vitro generated by fresh rat tissues co-incubation was consistent with its AOX expression. The result of the molecular docking analysis of DQ and AOX protein showed that DQ is capable of binding to AOX. Furthermore, the cytotoxicity of DQ was significantly higher than DQ-M at the same concentration tested in six cell types. This work is the first to uncover the involvement of aldehyde oxidase, a non-cytochrome P450 enzyme, in the oxidative metabolic pathway of diquat, thus providing a potential target for the development of detoxification treatment.


Assuntos
Aldeído Oxidase , Diquat , Ratos , Animais , Diquat/farmacologia , Aldeído Oxidase/química , Aldeído Oxidase/metabolismo , Simulação de Acoplamento Molecular , Estresse Oxidativo , Redes e Vias Metabólicas , Sistema Enzimático do Citocromo P-450/metabolismo
2.
Zhongguo Fei Ai Za Zhi ; 27(2): 126-132, 2024 Feb 20.
Artigo em Chinês | MEDLINE | ID: mdl-38453444

RESUMO

Liquid biopsy is gradually being applied in the clinical diagnosis and treatment of lung cancer. At present, with the development of metabolomics, more and more metabolic biomarkers are considered as potential sensitive markers reflecting the occurrence and development of tumors. This article summarizes the changes in the main metabolic pathways of lung cancer, including glucose metabolism, amino acid metabolism, lipid metabolism, sphingolipid metabolism, glycerophospholipid metabolism, and purine metabolism. Meanwhile, this article reviews the role of metabolic biomarkers in the early diagnosis of lung cancer, predicting disease progression, and evaluating the efficacy of chemotherapy and immunotherapy, aiming to provide effective biomarkers for tumor diagnosis and treatment.
.


Assuntos
Biomarcadores Tumorais , Neoplasias Pulmonares , Humanos , Biomarcadores Tumorais/metabolismo , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Metabolômica , Redes e Vias Metabólicas , Biópsia Líquida
3.
Proc Natl Acad Sci U S A ; 121(11): e2400519121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38457519
4.
Int J Surg ; 110(3): 1755-1769, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38484261

RESUMO

BACKGROUND: The gradual evolution of the detection and quantification of volatile organic compounds (VOCs) has been instrumental in cancer diagnosis. The primary objective of this study was to assess the diagnostic potential of exhaled breath and urinary VOCs in cancer detection. As VOCs are indicative of tumor and human metabolism, our work also sought to investigate the metabolic pathways linked to the development of cancerous tumors. MATERIALS AND METHODS: An electronic search was performed in the PubMed database. Original studies on VOCs within exhaled breath and urine for cancer detection with a control group were included. A meta-analysis was conducted using a bivariate model to assess the sensitivity and specificity of the VOCs for cancer detection. Fagan's nomogram was designed to leverage the findings from our diagnostic analysis for the purpose of estimating the likelihood of cancer in patients. Ultimately, MetOrigin was employed to conduct an analysis of the metabolic pathways associated with VOCs in relation to both human and/or microbiota. RESULTS: The pooled sensitivity, specificity and the area under the curve for cancer screening utilizing exhaled breath and urinary VOCs were determined to be 0.89, 0.88, and 0.95, respectively. A pretest probability of 51% can be considered as the threshold for diagnosing cancers with VOCs. As the estimated pretest probability of cancer exceeds 51%, it becomes more appropriate to emphasize the 'ruling in' approach. Conversely, when the estimated pretest probability of cancer falls below 51%, it is more suitable to emphasize the 'ruling out' approach. A total of 14, 14, 6, and 7 microbiota-related VOCs were identified in relation to lung, colorectal, breast, and liver cancers, respectively. The enrichment analysis of volatile metabolites revealed a significant enrichment of butanoate metabolism in the aforementioned tumor types. CONCLUSIONS: The analysis of exhaled breath and urinary VOCs showed promise for cancer screening. In addition, the enrichment analysis of volatile metabolites revealed a significant enrichment of butanoate metabolism in four tumor types, namely lung, colorectum, breast and liver. These findings hold significant implications for the prospective clinical application of multiomics correlation in disease management and the exploration of potential therapeutic targets.


Assuntos
Neoplasias Hepáticas , Compostos Orgânicos Voláteis , Humanos , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo , Estudos Prospectivos , Testes Respiratórios , Redes e Vias Metabólicas
5.
Appl Microbiol Biotechnol ; 108(1): 269, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38507095

RESUMO

Microalgae are rich in fatty acids, proteins, and other nutrients, which have gained the general attention of researchers all over the world. For the development of Chlorella vulgaris in food and feed industry, this study was conducted to investigate the differences in C. vulgaris' growth and nutritional components under different culture conditions (autotrophic, heterotrophic, photoheterotrophic) and the internal factors through cell counting in combination with transcriptome and nutrient analyses. The results showed that, under the photoheterotrophic condition, Chlorella's growth and the contents of lipid and protein were significantly higher than that under the heterotrophic condition, and the moisture content was lower than that under the heterotrophic condition. The saturated fatty acid content under the photoheterotrophic condition was the lowest, while the polyunsaturated fatty acid content was significantly higher than those under the other two conditions. There were 46,583 differentially expressed genes (DEGs), including 33,039 up-regulated DEGs (70.93%) and 13,544 down-regulated DEGs (29.07%), under the photoheterotrophic condition in comparison with the autotrophic condition. The fold change between the two conditions of samples of up-regulated genes was higher than that of the down-regulated genes. The KEGG enrichment showed that the up-regulated DEGs in the photoheterotrophic condition were significantly enriched in 5 pathways, including protein processing in endoplasmic reticulum pathway, photosynthesis pathway, photosynthesis-antenna protein pathway, endocytosis pathway, and phosphonate and phosphinate metabolism pathway. DEGs related to fatty acid metabolic pathways were significantly enriched in the fatty acid biosynthesis pathway and the biosynthesis of unsaturated fatty acid pathway. The qPCR analysis showed that the expression pattern of the selected genes was consistent with that of transcriptome analysis. The results of this study lay a theoretical foundation for the large-scale production of Chlorella and its application in food, feed, and biodiesel. KEY POINTS: • Nutrient levels under photoheterotrophic condition were higher than other conditions. • Six important pathways were discovered that affect changes in nutritional composition. • Explored genes encode important enzymes in the differential metabolic pathways.


Assuntos
Chlorella vulgaris , Microalgas , Ácidos Graxos/metabolismo , Fotossíntese , Redes e Vias Metabólicas , Nutrientes/análise , Biomassa , Microalgas/metabolismo , Biocombustíveis/análise
6.
Methods Mol Biol ; 2776: 305-320, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38502513

RESUMO

ChloroKB ( http://chlorokb.fr ) is a knowledge base providing synoptic representations of the metabolism of the model plant Arabidopsis thaliana and its regulation. Initially focused on plastid metabolism, ChloroKB now accounts for the metabolism throughout the cell. ChloroKB is based on the CellDesigner formalism. CellDesigner supports graphical notation and listing of the corresponding symbols based on the Systems Biology Graphical Notation. Thus, this formalism allows biologists to represent detailed biochemical processes in a way that can be easily understood and shared, facilitating communication between researchers. In this chapter, we will focus on a specificity of ChloroKB, the representation of multilayered regulation of protein activity. Information on regulation of protein activity is indeed central to understanding the plant response to fluctuating environmental conditions. However, the intrinsic diversity of the regulatory modes and the abundance of detail may hamper comprehension of the regulatory processes described in ChloroKB. With this chapter, ChloroKB users will be guided through the representation of these sophisticated biological processes of prime importance to understanding metabolism or for applied purposes. The descriptions provided, which summarize years of work and a broad bibliography in a few pages, can help speed up the integration of regulatory processes in kinetic models of plant metabolism.


Assuntos
Arabidopsis , Software , Biologia de Sistemas , Redes e Vias Metabólicas , Arabidopsis/metabolismo
7.
Arch Microbiol ; 206(4): 185, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38506928

RESUMO

This review provides a comprehensive overview of the key aspects of the natural metabolite production by endophytic fungi, which has attracted significant attention due to its diverse biological activities and wide range of applications. Synthesized by various fungal species, these metabolites encompass compounds with therapeutic, agricultural, and commercial significance. We delved into strategies and advancements aimed at optimizing fungal metabolite production. Fungal cultivation, especially by Aspergillus, Penicillium, and Fusarium, plays a pivotal role in metabolite biosynthesis, and researchers have explored both submerged and solid-state cultivation processes to harness the full potential of fungal species. Nutrient optimization, pH, and temperature control are critical factors in ensuring high yields of the targeted bioactive metabolites especially for scaling up processes. Analytical methods that includes High-Performance Liquid Chromatography (HPLC), Liquid Chromatography-Mass Spectrometry (LC-MS), Gas Chromatography-Mass Spectrometry (GC-MS), Nuclear Magnetic Resonance (NMR), and Mass Spectrometry (MS), are indispensable for the identification and quantification of the compounds. Moreover, genetic engineering and metabolic pathway manipulation have emerged as powerful tools to enhance metabolite production and develop novel fungal strains with increased yields. Regulation and control mechanisms at the genetic, epigenetic, and metabolic levels are explored to fine-tune the biosynthesis of fungal metabolites. Ongoing research aims to overcome the complexity of the steps involved to ensure the efficient production and utilization of fungal metabolites.


Assuntos
Fungos , Redes e Vias Metabólicas , Espectrometria de Massas , Fungos/genética , Fungos/metabolismo , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas
8.
Biotechnol J ; 19(3): e2300744, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38509791

RESUMO

NAD(P)H-dependent oxidoreductases are crucial biocatalysts for synthesizing chiral compounds. Yet, the industrial implementation of enzymatic redox reactions is often hampered by an insufficient supply of expensive nicotinamide cofactors. Here, a cofactor self-sufficient whole-cell biocatalyst was developed for the enzymatic asymmetric reduction of 2-oxo-4-[(hydroxy)(-methyl)phosphinyl] butyric acid (PPO) to L-phosphinothricin (L-PPT). The endogenous NADP+ pool was significantly enhanced by regulating Preiss-Handler pathway toward NAD(H) synthesis and, in the meantime, introducing NAD kinase to phosphorylate NAD(H) toward NADP+. The intracellular NADP(H) concentration displayed a 2.97-fold increase with the strategy compared with the wild-type strain. Furthermore, a recombinant multi-enzyme cascade biocatalytic system was constructed based on the Escherichia coli chassis. In order to balance multi-enzyme co-expression levels, the strategy of modulating rate-limiting enzyme PmGluDH by RBS strengths regulation successfully increased the catalytic efficiency of PPO conversion. Finally, the cofactor self-sufficient whole-cell biocatalyst effectively converted 300 mM PPO to L-PPT in 2 h without the need to add exogenous cofactors, resulting in a 2.3-fold increase in PPO conversion (%) from 43% to 100%, with a high space-time yield of 706.2 g L-1 d-1 and 99.9% ee. Overall, this work demonstrates a technological example for constructing a cofactor self-sufficient system for NADPH-dependent redox biocatalysis.


Assuntos
NADH NADPH Oxirredutases , NAD , NADP/metabolismo , NAD/metabolismo , NADH NADPH Oxirredutases/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Oxirredução , Redes e Vias Metabólicas
9.
Nat Commun ; 15(1): 2203, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38467616

RESUMO

The ability of CD8+ T cells to infiltrate solid tumors and reach cancer cells is associated with improved patient survival and responses to immunotherapy. Thus, identifying the factors controlling T cell migration in tumors is critical, so that strategies to intervene on these targets can be developed. Although interstitial motility is a highly energy-demanding process, the metabolic requirements of CD8+ T cells migrating in a 3D environment remain unclear. Here, we demonstrate that the tricarboxylic acid (TCA) cycle is the main metabolic pathway sustaining human CD8+ T cell motility in 3D collagen gels and tumor slices while glycolysis plays a more minor role. Using pharmacological and genetic approaches, we report that CD8+ T cell migration depends on the mitochondrial oxidation of glucose and glutamine, but not fatty acids, and both ATP and ROS produced by mitochondria are required for T cells to migrate. Pharmacological interventions to increase mitochondrial activity improve CD8+ T cell intratumoral migration and CAR T cell recruitment into tumor islets leading to better control of tumor growth in human xenograft models. Our study highlights the rationale of targeting mitochondrial metabolism to enhance the migration and antitumor efficacy of CAR T cells in treating solid tumors.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Humanos , Linfócitos T CD8-Positivos/metabolismo , Mitocôndrias/metabolismo , Neoplasias/patologia , Redes e Vias Metabólicas , Movimento Celular
10.
Methods Mol Biol ; 2760: 345-369, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38468098

RESUMO

The identification of essential genes is a key challenge in systems and synthetic biology, particularly for engineering metabolic pathways that convert feedstocks into valuable products. Assessment of gene essentiality at a genome scale requires large and costly growth assays of knockout strains. Here we describe a strategy to predict the essentiality of metabolic genes using binary classification algorithms. The approach combines elements from genome-scale metabolic models, directed graphs, and machine learning into a predictive model that can be trained on small knockout data. We demonstrate the efficacy of this approach using the most complete metabolic model of Escherichia coli and various machine learning algorithms for binary classification.


Assuntos
Algoritmos , Aprendizado de Máquina , Escherichia coli/genética , Escherichia coli/metabolismo , Genes Essenciais , Redes e Vias Metabólicas/genética
11.
Clin Transl Med ; 14(3): e1620, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38468489

RESUMO

As single-cell RNA sequencing enables the detailed clustering of T-cell subpopulations and facilitates the analysis of T-cell metabolic states and metabolite dynamics, it has gained prominence as the preferred tool for understanding heterogeneous cellular metabolism. Furthermore, the synergistic or inhibitory effects of various metabolic pathways within T cells in the tumour microenvironment are coordinated, and increased activity of specific metabolic pathways generally corresponds to increased functional activity, leading to diverse T-cell behaviours related to the effects of tumour immune cells, which shows the potential of tumour-specific T cells to induce persistent immune responses. A holistic understanding of how metabolic heterogeneity governs the immune function of specific T-cell subsets is key to obtaining field-level insights into immunometabolism. Therefore, exploring the mechanisms underlying the interplay between T-cell metabolism and immune functions will pave the way for precise immunotherapy approaches in the future, which will empower us to explore new methods for combating tumours with enhanced efficacy.


Assuntos
Neoplasias , Linfócitos T , Humanos , Imunoterapia/métodos , Neoplasias/genética , Neoplasias/terapia , Redes e Vias Metabólicas , Microambiente Tumoral
12.
Eur J Med Res ; 29(1): 199, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528586

RESUMO

BACKGROUND: Lipid metabolism changes occur in early Alzheimer's disease (AD) patients. Yet little is known about metabolic gene changes in early AD cortex. METHODS: The lipid metabolic genes selected from two datasets (GSE39420 and GSE118553) were analyzed with enrichment analysis. Protein-protein interaction network construction and correlation analyses were used to screen core genes. Literature analysis and molecular docking were applied to explore potential therapeutic drugs. RESULTS: 60 lipid metabolic genes differentially expressed in early AD patients' cortex were screened. Bioinformatics analyses revealed that up-regulated genes were mainly focused on mitochondrial fatty acid oxidation and mediating the activation of long-chain fatty acids, phosphoproteins, and cholesterol metabolism. Down-regulated genes were mainly focused on lipid transport, carboxylic acid metabolic process, and neuron apoptotic process. Literature reviews and molecular docking results indicated that ACSL1, ACSBG2, ACAA2, FABP3, ALDH5A1, and FFAR4 were core targets for lipid metabolism disorder and had a high binding affinity with compounds including adenosine phosphate, oxidized Photinus luciferin, BMS-488043, and candidate therapeutic drugs especially bisphenol A, benzo(a)pyrene, ethinyl estradiol. CONCLUSIONS: AD cortical lipid metabolism disorder was associated with the dysregulation of the PPAR signaling pathway, glycerophospholipid metabolism, adipocytokine signaling pathway, fatty acid biosynthesis, fatty acid degradation, ferroptosis, biosynthesis of unsaturated fatty acids, and fatty acid elongation. Candidate drugs including bisphenol A, benzo(a)pyrene, ethinyl estradiol, and active compounds including adenosine phosphate, oxidized Photinus luciferin, and BMS-488043 have potential therapeutic effects on cortical lipid metabolism disorder of early AD.


Assuntos
Doença de Alzheimer , Compostos Benzidrílicos , Indóis , Transtornos do Metabolismo dos Lipídeos , Fenóis , Piperazinas , Ácido Pirúvico , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Simulação de Acoplamento Molecular , Benzo(a)pireno , Ácidos Graxos/metabolismo , Redes e Vias Metabólicas , Etinilestradiol , Nucleotídeos de Adenina/metabolismo , Luciferinas
13.
J Proteome Res ; 23(3): 956-970, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38310443

RESUMO

We present compelling evidence for the existence of an extended innate viperin-dependent pathway, which provides crucial evidence for an adaptive response to viral agents, such as SARS-CoV-2. We show the in vivo biosynthesis of a family of novel endogenous cytosine metabolites with potential antiviral activities. Two-dimensional nuclear magnetic resonance (NMR) spectroscopy revealed a characteristic spin-system motif, indicating the presence of an extended panel of urinary metabolites during the acute viral replication phase. Mass spectrometry additionally enabled the characterization and quantification of the most abundant serum metabolites, showing the potential diagnostic value of the compounds for viral infections. In total, we unveiled ten nucleoside (cytosine- and uracil-based) analogue structures, eight of which were previously unknown in humans allowing us to propose a new extended viperin pathway for the innate production of antiviral compounds. The molecular structures of the nucleoside analogues and their correlation with an array of serum cytokines, including IFN-α2, IFN-γ, and IL-10, suggest an association with the viperin enzyme contributing to an ancient endogenous innate immune defense mechanism against viral infection.


Assuntos
COVID-19 , Humanos , Estrutura Molecular , SARS-CoV-2 , Imunidade Inata , Citosina , Redes e Vias Metabólicas , Antivirais
14.
PLoS Comput Biol ; 20(2): e1011381, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38386685

RESUMO

Metabolic profiling (metabolomics) aims at measuring small molecules (metabolites) in complex samples like blood or urine for human health studies. While biomarker-based assessment often relies on a single molecule, metabolic profiling combines several metabolites to create a more complex and more specific fingerprint of the disease. However, in contrast to genomics, there is no unique metabolomics setup able to measure the entire metabolome. This challenge leads to tedious and resource consuming preliminary studies to be able to design the right metabolomics experiment. In that context, computer assisted metabolic profiling can be of strong added value to design metabolomics studies more quickly and efficiently. We propose a constraint-based modelling approach which predicts in silico profiles of metabolites that are more likely to be differentially abundant under a given metabolic perturbation (e.g. due to a genetic disease), using flux simulation. In genome-scale metabolic networks, the fluxes of exchange reactions, also known as the flow of metabolites through their external transport reactions, can be simulated and compared between control and disease conditions in order to calculate changes in metabolite import and export. These import/export flux differences would be expected to induce changes in circulating biofluid levels of those metabolites, which can then be interpreted as potential biomarkers or metabolites of interest. In this study, we present SAMBA (SAMpling Biomarker Analysis), an approach which simulates fluxes in exchange reactions following a metabolic perturbation using random sampling, compares the simulated flux distributions between the baseline and modulated conditions, and ranks predicted differentially exchanged metabolites as potential biomarkers for the perturbation. We show that there is a good fit between simulated metabolic exchange profiles and experimental differential metabolites detected in plasma, such as patient data from the disease database OMIM, and metabolic trait-SNP associations found in mGWAS studies. These biomarker recommendations can provide insight into the underlying mechanism or metabolic pathway perturbation lying behind observed metabolite differential abundances, and suggest new metabolites as potential avenues for further experimental analyses.


Assuntos
Metaboloma , Metabolômica , Humanos , Metaboloma/genética , Genoma , Redes e Vias Metabólicas , Biomarcadores
15.
Ageing Res Rev ; 95: 102242, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38387517

RESUMO

Diseases of the central nervous system (CNS), including stroke, brain tumors, and neurodegenerative diseases, have a serious impact on human health worldwide, especially in elderly patients. The brain, which is one of the body's most metabolically dynamic organs, lacks fuel stores and therefore requires a continuous supply of energy substrates. Metabolic abnormalities are closely associated with the pathogenesis of CNS disorders. Post-translational modifications (PTMs) are essential regulatory mechanisms that affect the functions of almost all proteins. Succinylation, a broad-spectrum dynamic PTM, primarily occurs in mitochondria and plays a crucial regulatory role in various diseases. In addition to directly affecting various metabolic cycle pathways, succinylation serves as an efficient and rapid biological regulatory mechanism that establishes a connection between metabolism and proteins, thereby influencing cellular functions in CNS diseases. This review offers a comprehensive analysis of succinylation and its implications in the pathological mechanisms of CNS diseases. The objective is to outline novel strategies and targets for the prevention and treatment of CNS conditions.


Assuntos
Doenças do Sistema Nervoso Central , Lisina , Humanos , Idoso , Lisina/metabolismo , Proteínas/metabolismo , Processamento de Proteína Pós-Traducional , Doenças do Sistema Nervoso Central/terapia , Redes e Vias Metabólicas
16.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1869(3): 159462, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38307322

RESUMO

In eukaryotes, the de novo synthesis of sphingolipids (SLs) consists of multiple sequential steps which are compartmentalized between the endoplasmic reticulum and the Golgi apparatus. Studies over many decades have identified the enzymes in the pathway, their localization, topology and an array of regulatory mechanisms. However, little is known about the evolutionary forces that underly the generation of this complex pathway or of its anteome, i.e., the metabolic pathways that converge on the SL biosynthetic pathway and are essential for its activity. After briefly describing the pathway, we discuss the mechanisms by which the enzymes of the SL biosynthetic pathway are targeted to their different subcellular locations, how the pathway per se may have evolved, including its compartmentalization, and the relationship of the pathway to eukaryogenesis. We discuss the circular interdependence of the evolution of the SL pathway, and comment on whether current Darwinian evolutionary models are able to provide genuine mechanistic insight into how the pathway came into being.


Assuntos
Vias Biossintéticas , Esfingolipídeos , Esfingolipídeos/metabolismo , Redes e Vias Metabólicas , Eucariotos/metabolismo , Retículo Endoplasmático/metabolismo
17.
J Hazard Mater ; 466: 133655, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38310843

RESUMO

The extensive use of plastics has given rise to microplastics, a novel environmental contaminant that has sparked considerable ecological and environmental concerns. Biodegradation offers a more environmentally friendly approach to eliminating microplastics, but their degradation by marine microbial communities has received little attention. In this study, we used iron-enhanced marine sediment to augment the natural bacterial community and facilitate the decomposition of polyethylene (PE) microplastics. The introduction of iron-enhanced sediment engendered an augmented bacterial biofilm formation on the surface of polyethylene (PE), thereby leading to a more pronounced degradation effect. This novel observation has been ascribed to the oxidative stress-induced generation of a variety of oxygenated functional groups, including hydroxyl (-OH), carbonyl (-CO), and ether (-C-O) moieties, within the microplastic substrate. The analysis of succession in the community structure of sediment bacteria during the degradation phase disclosed that Acinetobacter and Pseudomonas emerged as the principal bacterial players in PE degradation. These taxa were directly implicated in oxidative metabolic pathways facilitated by diverse oxidase enzymes under iron-facilitated conditions. The present study highlights bacterial community succession as a new pivotal factor influencing the complex biodegradation dynamics of polyethylene (PE) microplastics. This investigation also reveals, for the first time, a unique degradation pathway for PE microplastics orchestrated by the multifaceted marine sediment microbiota. These novel insights shed light on the unique functional capabilities and internal biochemical mechanisms employed by the marine sediment microbiota in effectively degrading polyethylene microplastics.


Assuntos
Microbiota , Poluentes Químicos da Água , Microplásticos/farmacologia , Plásticos/análise , Polietileno/farmacologia , Ferro/análise , Poluentes Químicos da Água/análise , Bactérias , Sedimentos Geológicos/microbiologia , Redes e Vias Metabólicas
18.
Nat Commun ; 15(1): 1163, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38331894

RESUMO

The role of the serine/glycine metabolic pathway (SGP) has recently been demonstrated in tumors; however, the pathological relevance of the SGP in thyroid cancer remains unexplored. Here, we perform metabolomic profiling of 17 tumor-normal pairs; bulk transcriptomics of 263 normal thyroid, 348 papillary, and 21 undifferentiated thyroid cancer samples; and single-cell transcriptomes from 15 cases, showing the impact of mitochondrial one-carbon metabolism in thyroid tumors. High expression of serine hydroxymethyltransferase-2 (SHMT2) and methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) is associated with low thyroid differentiation scores and poor clinical features. A subpopulation of tumor cells with high mitochondrial one-carbon pathway activity is observed in the single-cell dataset. SHMT2 inhibition significantly compromises mitochondrial respiration and decreases cell proliferation and tumor size in vitro and in vivo. Collectively, our results highlight the importance of the mitochondrial one-carbon pathway in undifferentiated thyroid cancer and suggest that SHMT2 is a potent therapeutic target.


Assuntos
Multiômica , Neoplasias da Glândula Tireoide , Humanos , Glicina Hidroximetiltransferase/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Redes e Vias Metabólicas/genética , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo
19.
Science ; 383(6683): 589-590, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38330113

RESUMO

Plants measure the duration of metabolic activity to promote rapid growth in long days.


Assuntos
Arabidopsis , Fotoperíodo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Redes e Vias Metabólicas
20.
Sci Rep ; 14(1): 4031, 2024 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-38369518

RESUMO

Traditional alcoholic beverages have played a significant role in the cultural, social, and culinary fabric of societies worldwide for centuries. Studying the microbial community structure and their metabolic potential in such beverages is necessary to define product quality, safety, and consistency, as well as to explore associated biotechnological applications. In the present investigation, Illumina-based (MiSeq system) whole-genome shotgun sequencing was utilized to characterize the microbial diversity and conduct predictive gene function analysis of keem, a starter culture employed by the Jaunsari tribal community in India for producing various traditional alcoholic beverages. A total of 8,665,213 sequences, with an average base length of 151 bps, were analyzed using MG-RAST. The analysis revealed the dominance of bacteria (95.81%), followed by eukaryotes (4.11%), archaea (0.05%), and viruses (0.03%). At the phylum level, Actinobacteria (81.18%) was the most abundant, followed by Firmicutes (10.56%), Proteobacteria (4.00%), and Ascomycota (3.02%). The most predominant genera were Saccharopolyspora (36.31%), followed by Brevibacterium (15.49%), Streptomyces (9.52%), Staphylococcus (8.75%), Bacillus (4.59%), and Brachybacterium (3.42%). At the species level, the bacterial, fungal, and viral populations of the keem sample could be categorized into 3347, 57, and 106 species, respectively. Various functional attributes to the sequenced data were assigned using Cluster of Orthologous Groups (COG), Non-supervised Orthologous Groups (NOG), subsystem, and KEGG Orthology (KO) annotations. The most prevalent metabolic pathways included carbohydrate, lipid, and amino acid metabolism, as well as the biosynthesis of glycans, secondary metabolites, and xenobiotic biodegradation. Given the rich microbial diversity and its associated metabolic potential, investigating the transition of keem from a traditional starter culture to an industrial one presents a compelling avenue for future research.


Assuntos
Microbiota , Microbiota/genética , Bactérias , Firmicutes/genética , Archaea/genética , Redes e Vias Metabólicas
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