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1.
Respir Res ; 25(1): 206, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745285

RESUMO

BACKGROUND: Previous studies have largely neglected the role of sulfur metabolism in LUAD, and no study has combine iron, copper, and sulfur-metabolism associated genes together to create prognostic signatures. METHODS: This study encompasses 1564 LUAD patients, 1249 NSCLC patients, and over 10,000 patients with various cancer types from diverse cohorts. We employed the R package ConsensusClusterPlus to separate patients into different ICSM (Iron, Copper, and Sulfur-Metabolism) subtypes. Various machine-learning methods were utilized to develop the ICSMI. Enrichment analyses were conducted using ClusterProfiler and GSVA, while IOBR quantified immune cell infiltration. GISTIC2.0 and maftools were utilized for CNV and SNV data analysis. The Oncopredict package predicted drug information based on GDSC1. TIDE algorithm and cohorts GSE91061 and IMvigor210 evaluated patient response to immunotherapy. Single-cell data was processed using the Seurat package, AUCell package calculated cells geneset activity scores, and the Scissor algorithm identified ICSMI-associated cells. In vitro experiments was conducted to explore the role of ICSMRGs in LUAD. RESULTS: Unsupervised clustering identified two distinct ICSM subtypes of LUAD, each with unique clinical characteristics. The ICSMI, comprising 10 genes, was constructed using integrated machine-learning methods. Its prognostic power was validated in 10 independent datasets, revealing that LUAD patients with higher ICSMI levels had poorer prognoses. Furthermore, ICSMI demonstrated superior predictive abilities compared to 102 previously published signatures. A nomogram incorporating ICSMI and clinical features exhibited high predictive performance. ICSMI positively correlated with patients gene mutations, and integrated analysis of bulk and single-cell transcriptome data revealed its association with TME modulators. Cells representing the high-ICSMI phenotype exhibited more malignant features. LUAD patients with high ICSMI levels exhibited sensitivity to chemotherapy and targeted therapy but displayed resistance to immunotherapy. In a comprehensive analysis across various cancers, ICSMI retained significant prognostic value and emerged as a risk factor for the majority of cancer patients. CONCLUSIONS: ICSMI provides critical prognostic insights for LUAD patients, offering valuable insights into the tumor microenvironment and predicting treatment responsiveness.


Assuntos
Adenocarcinoma de Pulmão , Cobre , Ferro , Neoplasias Pulmonares , Aprendizado de Máquina , Enxofre , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/diagnóstico , Enxofre/metabolismo , Cobre/metabolismo , Prognóstico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/diagnóstico , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/tratamento farmacológico , Ferro/metabolismo , Resultado do Tratamento , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Valor Preditivo dos Testes , Masculino , Feminino
2.
Environ Microbiol Rep ; 16(3): e13263, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705733

RESUMO

Deep-sea methane seeps are amongst the most biologically productive environments on Earth and are often characterised by stable, low oxygen concentrations and microbial communities that couple the anaerobic oxidation of methane to sulfate reduction or iron reduction in the underlying sediment. At these sites, ferrous iron (Fe2+) can be produced by organoclastic iron reduction, methanotrophic-coupled iron reduction, or through the abiotic reduction by sulfide produced by the abundant sulfate-reducing bacteria at these sites. The prevalence of Fe2+in the anoxic sediments, as well as the availability of oxygen in the overlying water, suggests that seeps could also harbour communities of iron-oxidising microbes. However, it is unclear to what extent Fe2+ remains bioavailable and in solution given that the abiotic reaction between sulfide and ferrous iron is often assumed to scavenge all ferrous iron as insoluble iron sulfides and pyrite. Accordingly, we searched the sea floor at methane seeps along the Cascadia Margin for microaerobic, neutrophilic iron-oxidising bacteria, operating under the reasoning that if iron-oxidising bacteria could be isolated from these environments, it could indicate that porewater Fe2+ can persist is long enough for biology to outcompete pyritisation. We found that the presence of sulfate in our enrichment media muted any obvious microbially-driven iron oxidation with most iron being precipitated as iron sulfides. Transfer of enrichment cultures to sulfate-depleted media led to dynamic iron redox cycling relative to abiotic controls and sulfate-containing cultures, and demonstrated the capacity for biogenic iron (oxyhydr)oxides from a methane seep-derived community. 16S rRNA analyses revealed that removing sulfate drastically reduced the diversity of enrichment cultures and caused a general shift from a Gammaproteobacteria-domainated ecosystem to one dominated by Rhodobacteraceae (Alphaproteobacteria). Our data suggest that, in most cases, sulfur cycling may restrict the biological "ferrous wheel" in contemporary environments through a combination of the sulfur-adapted sediment-dwelling ecosystems and the abiotic reactions they influence.


Assuntos
Bactérias , Sedimentos Geológicos , Ferro , Metano , Oxirredução , Enxofre , Metano/metabolismo , Ferro/metabolismo , Enxofre/metabolismo , Sedimentos Geológicos/microbiologia , Sedimentos Geológicos/química , Bactérias/metabolismo , Bactérias/genética , Bactérias/classificação , Água do Mar/microbiologia , Água do Mar/química , Sulfetos/metabolismo , Sulfatos/metabolismo , RNA Ribossômico 16S/genética , Filogenia
3.
Molecules ; 29(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731499

RESUMO

Carbon nanodots (CDs) are commonly found in food products and have attracted significant attention from food scientists. There is a high probability of CD exposure in humans, but its impacts on health are unclear. Therefore, health effects associated with CD consumption should be investigated. In this study, we attempted to create a model system of the Maillard reaction between cystine and glucose using a simple cooking approach. The CDs (CG-CDs) were isolated from cystine-glucose-based Maillard reaction products and characterized using fluorescence spectroscopy, X-ray diffractometer (XRD), and transmission electron microscope (TEM). Furthermore, human mesenchymal stem cells (hMCs) were used as a model to unravel the CDs' cytotoxic properties. The physiochemical assessment revealed that CG-CDs emit excitation-dependent fluorescence and possess a circular shape with sizes ranging from 2 to 13 nm. CG-CDs are predominantly composed of carbon, oxygen, and sulfur. The results of the cytotoxicity evaluation indicate good biocompatibility, where no severe toxicity was observed in hMCs up to 400 µg/mL. The DPPH assay demonstrated that CDs exert potent antioxidant abilities. The qPCR analysis revealed that CDs promote the downregulation of the key regulatory genes, PPARγ, C/EBPα, SREBP-1, and HMGCR, coupled with the upregulation of anti-inflammatory genes. Our findings suggested that, along with their excellent biocompatibility, CG-CDs may offer positive health outcomes by modulating critical genes involved in lipogenesis, homeostasis, and obesity pathogenesis.


Assuntos
Proteína alfa Estimuladora de Ligação a CCAAT , Carbono , Reação de Maillard , Células-Tronco Mesenquimais , PPAR gama , Proteína de Ligação a Elemento Regulador de Esterol 1 , Humanos , Carbono/química , PPAR gama/genética , PPAR gama/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Pontos Quânticos/química , Regulação para Baixo/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Antioxidantes/farmacologia , Antioxidantes/química , Enxofre/química
4.
Mar Pollut Bull ; 202: 116356, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38604079

RESUMO

In this study, we focus on the development and validation of a deep learning (long short-term memory, LSTM)-based algorithm to predict the accidental spreading of LSFO (low sulfur fuel oil) on the water surface. The data for the training was obtained by numerical simulations of artificial geometries with different configurations of islands and shorelines and wind speeds (2.0-8.0 m/s). For simulating the spread of oils in O(102) km scales, the volume of fluid and discrete phase models were adopted, and the kinematic variables of particle location, particle velocity, and water velocity were collected as input features for LSTM model. The predicted spreading pattern of LSFO matched well with the simulation (less than 10 % in terms of the mean absolute error for the untrained data). Finally, we applied the model to the Wakashio LSFO spill accident, considering actual geometry and weather information, which confirmed the practical feasibility of the present model.


Assuntos
Óleos Combustíveis , Enxofre/química , Poluição por Petróleo , Poluentes Químicos da Água , Algoritmos , Modelos Teóricos , Simulação por Computador
5.
Dalton Trans ; 53(18): 7866-7879, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38632950

RESUMO

Rhenium(I) tricarbonyl complexes are widely studied for their cell imaging properties and anti-cancer and anti-microbial activities, but the complexes with S-donor ligands remain relatively unexplored. A series of six fac-[Re(NN)(CO)3(SR)] complexes, where (NN) is 2,2'-bipyridyl (bipy) or 1,10-phenanthroline (phen), and RSH is a series of thiocarboxylic acid methyl esters, have been synthesized and characterized. Cellular uptake and anti-proliferative activities of these complexes in human breast cancer cell lines (MDA-MB-231 and MCF-7) were generally lower than those of the previously described fac-[Re(NN)(CO)3(OH2)]+ complexes; however, one of the complexes, fac-[Re(CO)3(phen)(SC(Ph)CH2C(O)OMe)] (3b), was active (IC50 ∼ 10 µM at 72 h treatment) in thiol-depleted MDA-MB-231 cells. Moreover, unlike fac-[Re(CO)3(phen)(OH2)]+, this complex did not lose activity in the presence of extracellular glutathione. Taken together these properties show promise for further development of 3b and its analogues as potential anti-cancer drugs for co-treatment with thiol-depleting agents. Conversely, the stable and non-toxic complex, fac-[Re(bipy)(CO)3(SC(Me)C(O)OMe)] (1a), predominantly localized in the lysosomes of MDA-MB-231 cells, as shown by live cell confocal microscopy (λex = 405 nm, λem = 470-570 nm). It is strongly localized in a subset of lysosomes (25 µM Re, 4 h treatment), as shown by co-localization with a Lysotracker dye. Longer treatment times with 1a (25 µM Re for 48 h) resulted in partial migration of the probe into the mitochondria, as shown by co-localization with a Mitotracker dye. These properties make complex 1a an attractive target for further development as an organelle probe for multimodal imaging, including phosphorescence, carbonyl tag for vibrational spectroscopy, and Re tag for X-ray fluorescence microscopy.


Assuntos
Antineoplásicos , Proliferação de Células , Complexos de Coordenação , Rênio , Enxofre , Humanos , Rênio/química , Rênio/farmacologia , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Ligantes , Enxofre/química , Enxofre/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular
6.
J Phys Chem Lett ; 15(16): 4263-4267, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38607253

RESUMO

A novel covalent post-translational modification (lysine-NOS-cysteine) was discovered in proteins, initially in the enzyme transaldolase of Neisseria gonorrhoeae (NgTAL) [Nature 2021, 593, 460-464], acting as a redox switch. The identification of this novel linkage in solution was unprecedented until now. We present detection of the NOS redox switch in solution using sulfur K-edge X-ray absorption spectroscopy (XAS). The oxidized NgTAL spectrum shows a distinct shoulder on the low-energy side of the rising edge, corresponding to a dipole-allowed transition from the sulfur 1s core to the unoccupied σ* orbital of the S-O group in the NOS bridge. This feature is absent in the XAS spectrum of reduced NgTAL, where Lys-NOS-Cys is absent. Our experimental and calculated XAS data support the presence of a NOS bridge in solution, thus potentially facilitating future studies on enzyme activity regulation mediated by the NOS redox switches, drug discovery, biocatalytic applications, and protein design.


Assuntos
Oxirredução , Transaldolase , Espectroscopia por Absorção de Raios X , Cisteína/química , Cisteína/metabolismo , Lisina/química , Lisina/metabolismo , Neisseria gonorrhoeae/enzimologia , Neisseria gonorrhoeae/química , Processamento de Proteína Pós-Traducional , Soluções , Enxofre/química , Enxofre/metabolismo , Transaldolase/metabolismo , Transaldolase/química
7.
Nat Commun ; 15(1): 3269, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627381

RESUMO

Maturation of iron-sulfur proteins in eukaryotes is initiated in mitochondria by the core iron-sulfur cluster assembly (ISC) complex, consisting of the cysteine desulfurase sub-complex NFS1-ISD11-ACP1, the scaffold protein ISCU2, the electron donor ferredoxin FDX2, and frataxin, a protein dysfunctional in Friedreich's ataxia. The core ISC complex synthesizes [2Fe-2S] clusters de novo from Fe and a persulfide (SSH) bound at conserved cluster assembly site residues. Here, we elucidate the poorly understood Fe-dependent mechanism of persulfide transfer from cysteine desulfurase NFS1 to ISCU2. High-resolution cryo-EM structures obtained from anaerobically prepared samples provide snapshots that both visualize different stages of persulfide transfer from Cys381NFS1 to Cys138ISCU2 and clarify the molecular role of frataxin in optimally positioning assembly site residues for fast sulfur transfer. Biochemical analyses assign ISCU2 residues essential for sulfur transfer, and reveal that Cys138ISCU2 rapidly receives the persulfide without a detectable intermediate. Mössbauer spectroscopy assessing the Fe coordination of various sulfur transfer intermediates shows a dynamic equilibrium between pre- and post-sulfur-transfer states shifted by frataxin. Collectively, our study defines crucial mechanistic stages of physiological [2Fe-2S] cluster assembly and clarifies frataxin's molecular role in this fundamental process.


Assuntos
Frataxina , Proteínas Ferro-Enxofre , Proteínas Ferro-Enxofre/metabolismo , Sulfetos/metabolismo , Enxofre/metabolismo , Liases de Carbono-Enxofre/metabolismo , Proteínas de Ligação ao Ferro/metabolismo
8.
Molecules ; 29(8)2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38675602

RESUMO

Alzheimer's disease (AD) is a complex neurodegenerative disease that can lead to the loss of cognitive function. The progression of AD is regulated by multiple signaling pathways and their associated targets. Therefore, multitarget strategies theoretically have greater potential for treating AD. In this work, a series of new hybrids were designed and synthesized by the hybridization of tacrine (4, AChE: IC50 = 0.223 µM) with pyrimidone compound 5 (GSK-3ß: IC50 = 3 µM) using the cysteamine or cystamine group as the connector. The biological evaluation results demonstrated that most of the compounds exhibited moderate to good inhibitory activities against acetylcholinesterase (AChE) and glycogen synthase kinase 3ß (GSK-3ß). The optimal compound 18a possessed potent dual AChE/GSK-3ß inhibition (AChE: IC50 = 0.047 ± 0.002 µM, GSK-3ß: IC50 = 0.930 ± 0.080 µM). Further molecular docking and enzymatic kinetic studies revealed that this compound could occupy both the catalytic anionic site and the peripheral anionic site of AChE. The results also showed a lack of toxicity to SH-SY5Y neuroblastoma cells at concentrations of up to 25 µM. Collectively, this work explored the structure-activity relationships of novel tetrahydroacridin hybrids with sulfur-inserted linkers, providing a reference for the further research and development of new multitarget anti-AD drugs.


Assuntos
Acetilcolinesterase , Doença de Alzheimer , Inibidores da Colinesterase , Desenho de Fármacos , Glicogênio Sintase Quinase 3 beta , Simulação de Acoplamento Molecular , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Humanos , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Acetilcolinesterase/metabolismo , Acetilcolinesterase/química , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Glicogênio Sintase Quinase 3 beta/metabolismo , Linhagem Celular Tumoral , Enxofre/química , Relação Estrutura-Atividade , Acridinas/química , Acridinas/farmacologia , Acridinas/síntese química , Tacrina/química , Tacrina/farmacologia , Tacrina/síntese química , Estrutura Molecular
9.
Waste Manag ; 182: 44-54, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38636125

RESUMO

Pyrolysis can effectively convert waste tires into high-value products. However, the sulfur-containing compounds in pyrolysis oil and gas would significantly reduce the environmental and economic feasibility of this technology. Here, the desulfurization and upgrade of waste tire pyrolysis oil and gas were performed by adding different metal oxides (Fe2O3, CuO, and CaO). Results showed that Fe2O3 exhibited the highest removal efficiency of 87.7 % for the sulfur-containing gas at 600 °C with an outstanding removal efficiency of 99.5 % for H2S. CuO and CaO were slightly inferior to Fe2O3, with desulfurization efficiencies of 75.9 % and 45.2 % in the gas when added at 5 %. Fe2O3 also demonstrated a notable efficacy in eliminating benzothiophene, the most abundant sulfur compound in pyrolysis oil, with a removal efficiency of 78.1 %. Molecular dynamics simulations and experiments showed that the desulfurization mechanism of Fe2O3 involved the bonding of Fe-S, the breakage of C-S, dehydrogenation and oxygen migration process, which promoted the conversion of Fe2O3 to FeO, FeS and Fe2(SO4)3. Meanwhile, Fe2O3 enhanced the cyclization and dehydrogenation reaction, facilitating the upgrade of oil and gas (monocyclic aromatics to 57.4 % and H2 to 22.3 %). This study may be helpful for the clean and high-value conversion of waste tires.


Assuntos
Óxidos , Pirólise , Óxidos/química , Enxofre/química , Incineração/métodos , Compostos Férricos/química , Gases/química , Borracha/química , Compostos de Cálcio/química , Cobre
10.
Sci Rep ; 14(1): 9758, 2024 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684820

RESUMO

Our investigation revealed that alterations in sulphur (S) pools are predominantly governed by soil organic carbon (SOC), soil nitrogen (N), microbial biomass, and soil enzyme activities in sandy clay loam (Vertic Ustropept) soil. We employed ten sets of nutrient management techniques, ranging from suboptimal (50% RDF) to super-optimal doses (150% RDF), including NPK + Zn, NP, N alone, S-free NPK fertilizers, NPK + FYM, and control treatments, to examine the interrelation of S with SOC characteristics. Fourier-transform infrared (FT-IR) spectroscopy was utilized to analyze the functional groups present in SOC characterization across four treatments: 100% NPK, 150% NPK, NPK + FYM, and absolute control plots. Principal component analysis (PCA) was then applied to assess 29 minimal datasets, aiming to pinpoint specific soil characteristics influencing S transformation. In an Inceptisol, the application of fertilizers (100% RDF) in conjunction with 10 t ha-1 of FYM resulted in an increase of S pools from the surface to the subsurface stratum (OS > HSS > SO42--S > WSS), along with an increase in soil N and SOC. FT-IR spectroscopy identified cellulose and thiocyanate functional groups in all four plots, with a pronounced presence of carbohydrate-protein polyphenol, sulfoxide (S=O), and nitrate groups specifically observed in the INM plot. The PCA findings indicated that the primary factors influencing soil quality and crop productivity (r2 of 0.69) are SOC, SMBC, SMBN, SMBS, and the enzyme activity of URE, DHA, and AS. According to the study, the combined application of fertilizer and FYM (10 t ha-1) together exert a positive impact on sulphur transformation, SOC accumulation, and maize yield in sandy clay loam soil.


Assuntos
Carbono , Fertilizantes , Nitrogênio , Solo , Enxofre , Zea mays , Fertilizantes/análise , Enxofre/metabolismo , Enxofre/análise , Solo/química , Carbono/metabolismo , Carbono/análise , Zea mays/metabolismo , Zea mays/crescimento & desenvolvimento , Nitrogênio/metabolismo , Nitrogênio/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Milhetes/metabolismo , Biomassa , Agricultura/métodos , Microbiologia do Solo , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo
11.
Bioresour Technol ; 400: 130699, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38615966

RESUMO

Proposing recovery strategies to recover heavy-metal-inhibited sulfur-driven denitrification, as well as disclosing recovery mechanisms, can provide technical support for the stable operation of bio-systems. This study proposed an effective bio-promoter (mediator-promoter composed of L-cysteine, biotin, cytokinin, and anthraquinone-2,6-disulfonate) to recover Cr(VI) inhibited sulfur-driven denitrification, which effectively reduced the recovery time of NO3--N reduction (18-21 cycles) and NO2--N reduction (27-42 cycles) compared with self-recovery. The mediator-promoter repaired microbial damage by promoting intracellular chromium efflux. Moreover, the mediator-promoter reduced the accumulated reactive oxygen species by stimulating the secretion of antioxidant enzymes, reaching equilibrium in the oxidative-antioxidant system. To improve electron transmission, the mediator-promoter restored S2O32- oxidation to provide adequate electron donors and increased electron transfer rate by increasing cytochrome c levels. Mediator-promoter boosted the abundance of Thiobacillus (sulfur-oxidizing bacterium) and Simplicispira (denitrifying bacterium), which were positively correlated, facilitating the rapid denitrification recovery and the long-term stable operation of recovered systems.


Assuntos
Cromo , Desnitrificação , Enxofre , Cromo/metabolismo , Enxofre/farmacologia , Enxofre/química , Transporte de Elétrons , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Thiobacillus/metabolismo , Antraquinonas/farmacologia , Cisteína/farmacologia , Cisteína/metabolismo
12.
Sci Total Environ ; 927: 171689, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38492599

RESUMO

Sulfur plays an essential role in agricultural production, but few studies have been reported on how sulfur simultaneously impacts the transformation of cadmium (Cd) and arsenic (As) in the soil-rice system. This research selected two soils co-contaminated with both Cd and As, varying in acidity and alkalinity levels, to study the impacts of elemental sulfur (S) and calcium sulfate (CaSO4) on the migration and accumulation of Cd and As by rice. Results indicated that two types of sulfur had a substantial (P < 0.05) impact on decreasing the contents of Cd (28.3-50.4 %) and As (20.1-38.6 %) in brown rice in acidic and alkaline soils. They also increased rice biomass (29.3-112.8 %) and reduced Cd transport coefficient (27.2-45.6 %) significantly (P < 0.05). Notably, sulfur augmented the generation of iron plaque on rice root surfaces, which increased the fixation of Cd (17.6-61.0 %) and As (14.0-45.9 %). SEM-EDS results also indicated that the rice root surface exhibited significant enrichment of Fe, Cd, and As. The mechanism of simultaneous Cd and As immobilization by sulfur application was mainly ascribed to the contribution of iron plaque. Additionally, sulfur reduced the contents of Cd and As in soil porewater and promoted the transformation of As(III) to As(V) to reduce the toxicity of As. The K-edge XAFS of As in iron plaque also confirmed that sulfur application significantly promoted As(III) oxidation. Sulfur also promoted the activities of antioxidant enzymes and the contents of NPT, GSH, and PCs in rice plants. In general, this study establishes a foundation for sulfur to lower As and Cd bioavailability in paddy soils, enhance iron plaque and rice resistance, and reduce heavy metal accumulation.


Assuntos
Arsênio , Cádmio , Ferro , Oryza , Poluentes do Solo , Solo , Enxofre , Solo/química
13.
Sci Transl Med ; 16(739): eadg5553, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38507470

RESUMO

Glioblastoma, the most lethal primary brain tumor, harbors glioma stem cells (GSCs) that not only initiate and maintain malignant phenotypes but also enhance therapeutic resistance. Although frequently mutated in glioblastomas, the function and regulation of PTEN in PTEN-intact GSCs are unknown. Here, we found that PTEN directly interacted with MMS19 and competitively disrupted MMS19-based cytosolic iron-sulfur (Fe-S) cluster assembly (CIA) machinery in differentiated glioma cells. PTEN was specifically succinated at cysteine (C) 211 in GSCs compared with matched differentiated glioma cells. Isotope tracing coupled with mass spectrometry analysis confirmed that fumarate, generated by adenylosuccinate lyase (ADSL) in the de novo purine synthesis pathway that is highly activated in GSCs, promoted PTEN C211 succination. This modification abrogated the interaction between PTEN and MMS19, reactivating the CIA machinery pathway in GSCs. Functionally, inhibiting PTEN C211 succination by reexpressing a PTEN C211S mutant, depleting ADSL by shRNAs, or consuming fumarate by the US Food and Drug Administration-approved prescription drug N-acetylcysteine (NAC) impaired GSC maintenance. Reexpressing PTEN C211S or treating with NAC sensitized GSC-derived brain tumors to temozolomide and irradiation, the standard-of-care treatments for patients with glioblastoma, by slowing CIA machinery-mediated DNA damage repair. These findings reveal an immediately practicable strategy to target GSCs to treat glioblastoma by combination therapy with repurposed NAC.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Glioblastoma/tratamento farmacológico , Ferro/metabolismo , Glioma/tratamento farmacológico , Neoplasias Encefálicas/tratamento farmacológico , Células-Tronco Neoplásicas/patologia , Enxofre/metabolismo , Enxofre/uso terapêutico , Fumaratos , Linhagem Celular Tumoral , PTEN Fosfo-Hidrolase/metabolismo
14.
Genome Biol Evol ; 16(3)2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38447079

RESUMO

Selenocysteine, the 21st amino acid specified by the genetic code, is a rare selenium-containing residue found in the catalytic site of selenoprotein oxidoreductases. Selenocysteine is analogous to the common cysteine amino acid, but its selenium atom offers physical-chemical properties not provided by the corresponding sulfur atom in cysteine. Catalytic sites with selenocysteine in selenoproteins of vertebrates are under strong purifying selection, but one enzyme, glutathione peroxidase 6 (GPX6), independently exchanged selenocysteine for cysteine <100 million years ago in several mammalian lineages. We reconstructed and assayed these ancient enzymes before and after selenocysteine was lost and up to today and found them to have lost their classic ability to reduce hydroperoxides using glutathione. This loss of function, however, was accompanied by additional amino acid changes in the catalytic domain, with protein sites concertedly changing under positive selection across distant lineages abandoning selenocysteine in glutathione peroxidase 6. This demonstrates a narrow evolutionary range in maintaining fitness when sulfur in cysteine impairs the catalytic activity of this protein, with pleiotropy and epistasis likely driving the observed convergent evolution. We propose that the mutations shared across distinct lineages may trigger enzymatic properties beyond those in classic glutathione peroxidases, rather than simply recovering catalytic rate. These findings are an unusual example of adaptive convergence across mammalian selenoproteins, with the evolutionary signatures possibly representing the evolution of novel oxidoreductase functions.


Assuntos
Selênio , Selenocisteína , Animais , Selenocisteína/genética , Selenocisteína/química , Selenocisteína/metabolismo , Cisteína/genética , Cisteína/metabolismo , Selênio/metabolismo , Selenoproteínas/genética , Selenoproteínas/química , Selenoproteínas/metabolismo , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Aminoácidos , Glutationa , Enxofre , Mamíferos/genética , Mamíferos/metabolismo
15.
PLoS One ; 19(3): e0298999, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38526988

RESUMO

Sulfurtransferases transfer of sulfur atoms from thiols to acceptors like cyanide. They are categorized as thiosulfate sulfurtransferases (TSTs) and 3-mercaptopyruvate sulfurtransferases (MSTs). TSTs transfer sulfur from thiosulfate to cyanide, producing thiocyanate. MSTs transfer sulfur from 3-mercaptopyruvate to cyanide, yielding pyruvate and thiocyanate. The present study aimed to isolate and characterize the sulfurtransferase FrST from Frondihabitans sp. PAMC28461 using biochemical and structural analyses. FrST exists as a dimer and can be classified as a TST rather than an MST according to sequence-based clustering and enzyme activity. Furthermore, the discovery of activity over a wide temperature range and the broad substrate specificity exhibited by FrST suggest promising prospects for its utilization in industrial applications, such as the detoxification of cyanide.


Assuntos
Cisteína/análogos & derivados , Tiocianatos , Tiossulfatos , Sulfurtransferases/química , Tiossulfato Sulfurtransferase , Ácido Pirúvico , Cianetos , Enxofre
16.
Chemosphere ; 355: 141726, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38521105

RESUMO

Polymer stabilization, exemplified by carboxymethyl cellulose (CMC), has demonstrated effectiveness in enhancing the transport of nanoscale zero-valent iron (nZVI). And, sulfidation is recognized for enhancing the reactivity and selectivity of nZVI in dechlorination processes. The influence of polymer stabilization on sulfidated nZVI (S-nZVI) with various sulfur precursors remains unclear. In this study, CMC-stabilized S-nZVI (CMC-S-nZVI) was synthesized using three distinct sulfur precursors (S2-, S2O42-, and S2O32-) through one-step approach. The antioxidant properties of CMC significantly elevated the concentration of reduced sulfur species (S2-) on CMC-S-nZVIs, marking a 3.1-7.0-fold increase compared to S-nZVIs. The rate of trichloroethylene degradation (km) by CMC-S-nZVIs was observed to be 2.2-9.0 times higher than that achieved by their non-stabilized counterparts. Among the three CMC-S-nZVIs, CMC-S-nZVINa2S exhibited the highest km. Interesting, while the electron efficiency of CMC-S-nZVIs surged by 7.9-12 times relative to nZVI, it experienced a reduction of 7.0-34% when compared with S-nZVIs. This phenomenon is attributed to the increased hydrophilicity of S-nZVI particles due to CMC stabilization, which inadvertently promotes the hydrogen evolution reaction (HER). In conclusion, the findings of this study underscores the impact of CMC stabilization on the properties and dechlorination performance of S-nZVI sulfidated using different sulfur precursors, offering guidance for engineering CMC-S-nZVIs with desirable properties for contaminated groundwater remediation.


Assuntos
Água Subterrânea , Tricloroetileno , Poluentes Químicos da Água , Carboximetilcelulose Sódica , Ferro , Enxofre , Polímeros
17.
Waste Manag ; 179: 99-109, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38471253

RESUMO

Fast co-pyrolysis offers a sustainable solution for upcycling polymer waste, including scrap tyre and plastics. Previous studies primarily focused on slow heating rates, neglecting synergistic mechanisms and sulphur transformation in co-pyrolysis with tyre. This research explored fast co-pyrolysis of scrap tyre with polypropylene (PP), low-density polyethylene (LDPE), and polystyrene (PS) to understand synergistic effects and sulphur transformation mechanisms. A pronounced synergy was observed between scrap tyre and plastics, with the nature of the synergy being plastic-type dependent. Remarkably, blending 75 wt% PS or LDPE with tyre effectively eliminated sulphur-bearing compounds in the liquid product. This reduction in sulphur content can substantially mitigate the release of hazardous materials into the environment, emphasizing the environmental significance of co-pyrolysis. The synergy between PP or LDPE and tyre amplified the production of lighter hydrocarbons, while PS's interaction led to the creation of monocyclic aromatics. These findings offer insights into the intricate chemistry of scrap tyre and plastic interactions and highlight the potential of co-pyrolysis in waste management. By converting potential pollutants into valuable products, this method can significantly reduce the release of hazardous materials into the environment.


Assuntos
Temperatura Alta , Polietileno , Polietileno/química , Pirólise , Polipropilenos , Poliestirenos , Enxofre , Substâncias Perigosas , Plásticos/química
18.
ACS Appl Mater Interfaces ; 16(12): 14489-14502, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38478962

RESUMO

Multimodal tumor therapy with nanotechnology is an effective and integrative strategy to overcome the limitations of therapeutic efficacy and possible side effects associated with monotherapy. However, the construction of multimodal treatment nanoplatforms often involves various functional components, leading to certain challenges, such as time-consuming synthesis processes, low product yield, and inadequate biocompatibility. To address these issues, we have developed a straightforward method for preparing ultrathin Cu9S5 nanosheets (NSs) with surface defects for photothermal/photodynamic/chemodynamic therapy. The ultrathin morphology of the Cu9S5 NSs (with 2-3 nm) not only confers excellent biocompatibility but also enables broad-spectrum absorption with a remarkable photothermal conversion efficiency (58.96%) under 1064 nm laser irradiation. Moreover, due to the presence of a S vacancy, these Cu9S5 NSs exhibit favorable enzyme-like properties, including reactive oxygen species generation and glutathione consumption, particularly under laser irradiation. The efficacy of related tumor therapy and antibacterial treatment is significantly enhanced by the synergistic activation of photothermal/photodynamic/chemodynamic therapy through 1064 nm laser irradiation, as demonstrated by both in vitro and in vivo experiments. This study presents a novel strategy for multimodal tumor therapy with the prepared ultrathin Cu9S5 NSs, which holds promising pathways for photodynamic therapy in the NIR-II region.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Neoplasias/tratamento farmacológico , Terapia Combinada , Fototerapia , Enxofre , Linhagem Celular Tumoral
19.
Exp Cell Res ; 437(1): 114007, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38499142

RESUMO

Gastric cancer metastasis is a major cause of poor prognosis. Our previous research showed that methionine restriction (MR) lowers the invasiveness and motility of gastric carcinoma. In this study, we investigated the particular mechanisms of MR on gastric carcinoma metastasis. In vitro, gastric carcinoma cells (AGS, SNU-5, MKN7, KATO III, SNU-1, and MKN45) were grown in an MR medium for 24 h. In vivo, BALB/c mice were given a methionine-free (Met-) diet. Transwell assays were used to investigate cell invasion and migration. The amounts of Krüppel like factor 10 (KLF10) and cystathionine ß-synthase (CBS) were determined using quantitative real-time PCR and Western blot. To determine the relationship between KLF10 and CBS, chromatin immunoprecipitation and a dual-luciferase reporter experiment were used. Hematoxylin-eosin staining was used to detect lung metastasis. Liquid chromatography-mass spectrometry was used to determine cystathionine content. MR therapy had varying effects on the invasion and migration of gastric carcinoma cells AGS, SNU-5, MKN7, KATO III, SNU-1, and MKN45. KLF10 was highly expressed in AGS cells but poorly expressed in KATO III cells. KLF10 improved MR's ability to prevent gastric carcinoma cell invasion and migration. In addition, KLF10 may interact with CBS, facilitating transcription. Further detection revealed that inhibiting the KLF10/CBS-mediated trans-sulfur pathway lowered Met-'s inhibitory effect on lung metastasis development. KLF10 transcription activated CBS, accelerated the trans-sulfur pathway, and increased gastric carcinoma cells' susceptibility to MR.


Assuntos
Carcinoma , Neoplasias Pulmonares , Neoplasias Gástricas , Camundongos , Animais , Metionina/metabolismo , Cistationina beta-Sintase/genética , Cistationina beta-Sintase/metabolismo , Neoplasias Gástricas/patologia , Racemetionina , Enxofre , Neoplasias Pulmonares/genética , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Fatores de Transcrição de Resposta de Crescimento Precoce/metabolismo
20.
J Med Case Rep ; 18(1): 134, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38439039

RESUMO

BACKGROUND: This case report documents a case of malignant pheochromocytoma manifested as vision changes with lung metastasis and recurrence. CASE PRESENTATION: A 10-year-old Han Chinese girl presented with vision changes and was eventually diagnosed with pheochromocytoma by contrast-enhanced computed tomography, urine vanillylmandelic acid. After medication for hypertension and surgery, clinical symptoms disappeared. Malignant pheochromocytoma with lung metastasis was confirmed histologically using the Pheochromocytoma of the Adrenal Gland Scaled Score scoring system and genetically with succinate dehydrogenase complex iron sulfur subunit B mutation, and 3 months later, unplanned surgery was performed because of the high risks and signs of recurrence. She is asymptomatic as of the writing of this case report. Our patient's case highlights the importance of considering a diagnosis of malignant pheochromocytoma, and long-term follow-up for possible recurrence. CONCLUSION: Although there are well-recognized classic clinical manifestations associated with pheochromocytoma, atypical presentation, such as vision changes in children, should be considered. In addition, malignant pheochromocytoma children with a high Pheochromocytoma of the Adrenal Gland Scaled Score and succinate dehydrogenase complex iron sulfur subunit B mutation require a long-term follow-up or even unplanned surgery because of the higher risk of recurrence.


Assuntos
Neoplasias das Glândulas Suprarrenais , Neoplasias Pulmonares , Feocromocitoma , Feminino , Humanos , Criança , Feocromocitoma/diagnóstico , Feocromocitoma/cirurgia , Succinato Desidrogenase/genética , Enxofre , Ferro
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