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1.
Antonie Van Leeuwenhoek ; 117(1): 94, 2024 Jul 02.
Article de Anglais | MEDLINE | ID: mdl-38954064

RÉSUMÉ

The Aeolian archipelago is known worldwide for its volcanic activity and hydrothermal emissions, of mainly carbon dioxide and hydrogen sulfide. Hydrogen, methane, and carbon monoxide are minor components of these emissions which together can feed large quantities of bacteria and archaea that do contribute to the removal of these notorious greenhouse gases. Here we analyzed the metagenome of samples taken from the Levante bay on Vulcano Island, Italy. Using a gene-centric approach, the hydrothermal vent community appeared to be dominated by Proteobacteria, and Sulfurimonas was the most abundant genus. Metabolic reconstructions highlight a prominent role of formaldehyde oxidation and the reverse TCA cycle in carbon fixation. [NiFe]-hydrogenases seemed to constitute the preferred strategy to oxidize H2, indicating that besides H2S, H2 could be an essential electron donor in this system. Moreover, the sulfur cycle analysis showed a high abundance and diversity of sulfate reduction genes underpinning the H2S production. This study covers the diversity and metabolic potential of the microbial soil community in Levante bay and adds to our understanding of the biogeochemistry of volcanic ecosystems.


Sujet(s)
Hydrogène , Métagénome , Méthane , Microbiologie du sol , Soufre , Méthane/métabolisme , Hydrogène/métabolisme , Italie , Soufre/métabolisme , Archéobactéries/génétique , Archéobactéries/classification , Archéobactéries/métabolisme , Bactéries/génétique , Bactéries/classification , Bactéries/métabolisme , Bactéries/isolement et purification , Cheminées hydrothermales/microbiologie , Iles , Phylogenèse
2.
Methods Mol Biol ; 2839: 261-289, 2024.
Article de Anglais | MEDLINE | ID: mdl-39008260

RÉSUMÉ

Iron-sulfur (Fe-S) clusters are essential redox-active metallocofactors participating in electron transfer, radical chemistry, primary metabolism, and gene regulation. Successful trafficking and incorporation of Fe-S clusters into target proteins are critical to proper cellular function. While biophysical studies of isolated Fe-S proteins provide insight into the structure and function of these inorganic cofactors, few strategies currently exist to directly interrogate Fe-S cluster binding within a cellular environment. Here, we describe a chemoproteomic platform to report on Fe-S cluster incorporation and occupancy directly within a native proteome, enabling the characterization of Fe-S biogenesis pathways and the identification of undiscovered Fe-S proteins.


Sujet(s)
Ferrosulfoprotéines , Protéomique , Ferrosulfoprotéines/métabolisme , Ferrosulfoprotéines/composition chimique , Protéomique/méthodes , Liaison aux protéines , Protéome , Fer/métabolisme , Soufre/métabolisme , Oxydoréduction
3.
Water Environ Res ; 96(6): e11056, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38825347

RÉSUMÉ

Nitrate poses a potential threat to aquatic ecosystems. This study focuses on the sulfur autotrophic denitrification mechanism in the process of water culture wastewater treatment, which has been successfully applied to the degradation of nitrogen in water culture farm effluents. However, the coexistence of organic acids in the treatment process is a common environmental challenge, significantly affecting the activity of denitrifying bacteria. This paper aims to explore the effects of adding benzoic acid and lactic acid on denitrification performance, organic acid removal rate, and microbial population abundance in sulfur autotrophic denitrification systems under optimal operating conditions, sulfur deficiency, and high hydraulic load. In experiments with 50 mg·L-1 of benzoic acid or lactic acid alone, the results show that benzoic acid and lactic acid have a stimulating effect on denitrification activity, with the stimulating effect significantly greater than the inhibitory effect. Under optimal operating conditions, the average denitrification rate of the system remained above 99%; under S/N = 1.5 conditions, the average denitrification rate increased from 88.34% to 91.93% and 85.91%; under HRT = 6 h conditions, the average denitrification rate increased from 75.25% to 97.79% and 96.58%. In addition, the addition of organic acids led to a decrease in microbial population abundance. At the phylum level, Proteobacteria has always been the dominant bacterial genus, and its relative abundance significantly increased after the addition of benzoic acid, from 40.2% to 61.5% and 62.4%. At the genus level, Thiobacillus, Sulfurimonas, Chryseobacterium, and Thermomonas maintained high population abundances under different conditions. PRACTITIONER POINTS: Employing autotrophic denitrification process for treating high-nitrate wastewater. Utilizing organic acids as external carbon sources. Denitrifying bacteria demonstrate high utilization efficiency towards organic acids. Organic acids promote denitrification more than they inhibit it. The promotion is manifested in the enhancement of activity and microbial abundance.


Sujet(s)
Processus autotrophes , Acide benzoïque , Dénitrification , Acide lactique , Soufre , Acide benzoïque/métabolisme , Soufre/métabolisme , Acide lactique/métabolisme , Bactéries/métabolisme , Bactéries/classification , Microbiote/effets des médicaments et des substances chimiques , Élimination des déchets liquides/méthodes , Purification de l'eau/méthodes
4.
Molecules ; 29(12)2024 Jun 13.
Article de Anglais | MEDLINE | ID: mdl-38930878

RÉSUMÉ

Aurones, particular polyphenolic compounds belonging to the class of minor flavonoids and overlooked for a long time, have gained significative attention in medicinal chemistry in recent years. Indeed, considering their unique and outstanding biological properties, they stand out as an intriguing reservoir of new potential lead compounds in the drug discovery context. Nevertheless, several physicochemical, pharmacokinetic, and pharmacodynamic (P3) issues hinder their progression in more advanced phases of the drug discovery pipeline, making lead optimization campaigns necessary. In this context, scaffold hopping has proven to be a valuable approach in the optimization of natural products. This review provides a comprehensive and updated picture of the scaffold-hopping approaches directed at the optimization of natural and synthetic aurones. In the literature analysis, a particular focus is given to nitrogen and sulfur analogues. For each class presented, general synthetic procedures are summarized, highlighting the key advantages and potential issues. Furthermore, the biological activities of the most representative scaffold-hopped compounds are presented, emphasizing the improvements achieved and the potential for further optimization compared to the aurone class.


Sujet(s)
Azote , Soufre , Azote/composition chimique , Humains , Soufre/composition chimique , Benzofuranes/composition chimique , Benzofuranes/synthèse chimique , Benzofuranes/pharmacologie , Produits biologiques/composition chimique , Produits biologiques/pharmacologie , Relation structure-activité , Découverte de médicament/méthodes , Animaux , Structure moléculaire
5.
BMC Plant Biol ; 24(1): 607, 2024 Jun 26.
Article de Anglais | MEDLINE | ID: mdl-38926889

RÉSUMÉ

BACKGROUND: Salinity is a major abiotic stress, and the use of saline water in the agricultural sector will incur greater demand under the current and future climate changing scenarios. The objective of this study was to develop a dual-functional nanofertilizer capable of releasing a micronutrient that nourishes plant growth while enhancing salt stress resilience in faba bean (Vicia faba L.). RESULTS: Moringa oleifera leaf extract was used to synthesize sulfur nanoparticles (SNPs), which were applied as a foliar spray at different concentrations (0, 25, 50, and 100 mg/l) to mitigate the negative effects of salt stress (150 mM NaCl) on faba bean plants. The SNPs were characterized and found to be spherical in shape with an average size of 10.98 ± 2.91 nm. The results showed that salt stress had detrimental effects on the growth and photosynthetic performance (Fv/Fm) of faba bean compared with control, while foliar spraying with SNPs improved these parameters under salinity stress. SNPs application also increased the levels of osmolytes (soluble sugars, amino acids, proline, and glycine betaine) and nonenzymatic antioxidants, while reducing the levels of oxidative stress biomarkers (MDA and H2O2). Moreover, SNPs treatment under salinity stress stimulated the activity of antioxidant enzymes (ascorbate peroxidase (APX), and peroxidase (POD), polyphenol oxidase (PPO)) and upregulated the expression of stress-responsive genes: chlorophyll a-b binding protein of LHCII type 1-like (Lhcb1), ribulose bisphosphate carboxylase large chain-like (RbcL), cell wall invertase I (CWINV1), ornithine aminotransferase (OAT), and ethylene-responsive transcription factor 1 (ERF1), with the greatest upregulation observed at 50 mg/l SNPs. CONCLUSION: Overall, foliar application of sulfur nanofertilizers in agriculture could improve productivity while minimizing the deleterious effects of salt stress on plants. Therefore, this study provides a strong foundation for future research focused on evaluating the replacement of conventional sulfur-containing fertilizers with their nanoforms to reduce the harmful effects of salinity stress and enhance the productivity of faba beans.


Sujet(s)
Engrais , Nanoparticules , Stress salin , Soufre , Vicia faba , Vicia faba/physiologie , Vicia faba/effets des médicaments et des substances chimiques , Vicia faba/croissance et développement , Vicia faba/génétique , Soufre/métabolisme , Antioxydants/métabolisme , Feuilles de plante/effets des médicaments et des substances chimiques , Photosynthèse/effets des médicaments et des substances chimiques
6.
Arch Microbiol ; 206(7): 300, 2024 Jun 11.
Article de Anglais | MEDLINE | ID: mdl-38861201

RÉSUMÉ

Microorganisms produce diverse classes of metabolites under various physiological conditions. Many bacterial strains have been reported to carry out the process of desulfurization in a cost-effective manner by converting dibenzothiophene (DBT) into 2-hydroxybiphenyl (2-HBP) and then using the 2-HBP as a carbon source for growth and development. Key rate-limiting factors and an increased concentration of 2HBP (400 µM) affect the biodesulfurization activity of bacteria through the produced metabolites. Thus, this study was designed to explore the nature of the metabolites produced by Rhodococcus erythropolis in the presence of DBT and 2HBP supplemented with a culture medium. A total of 330 metabolites were detected, and the key metabolites identified were 11Z-eicosaenoyl-EA, 1-carboxyethylisoleucine, 1(3)-glyceryl-PGF2alpha, taurine, 2-hydroxynicotinic acid, 4,4-dimethyl-14alpha-hydroxymethyl-5alpha-cholest-8-en-3beta-ol, and 10-nitrooleic acid. The supplementation of DBT and DBT-2HBP resulted in the differential regulation of these metabolites, either through downregulation or overexpression. Furthermore, at high concentrations of 2-HBP, 1-carboxyethylisoleucine, taurine, 2-hydroxynicotinic acid, and nicotinic acid were upregulated. This work proposes that the identified metabolites may play a role in bacteria-mediated desulphurization and could be beneficial in developing a cost-effective method of desulphurization for refining petroleum.


Sujet(s)
Dérivés du biphényle , Pétrole , Rhodococcus , Thiophènes , Rhodococcus/métabolisme , Rhodococcus/croissance et développement , Pétrole/métabolisme , Dérivés du biphényle/métabolisme , Thiophènes/métabolisme , Dépollution biologique de l'environnement , Milieux de culture/composition chimique , Milieux de culture/métabolisme , Soufre/métabolisme
7.
Int J Mol Sci ; 25(11)2024 May 30.
Article de Anglais | MEDLINE | ID: mdl-38892213

RÉSUMÉ

The family Beggiatoaceae is currently represented by 25 genera in the Genome Taxonomy Database, of which only 6 have a definite taxonomic status. Two metagenome-assembled genomes (MAGs), WS_Bin1 and WS_Bin3, were assembled from metagenomes of the sulfur mats coating laminaria remnants in the White Sea. Using the obtained MAGs, we first applied phylogenetic analysis based on whole-genome sequences to address the systematics of Beggiatoaceae, which clarify the taxonomy of this family. According to the average nucleotide identity (ANI) and average amino acid identity (AAI) values, MAG WS_Bin3 was assigned to a new genus and a new species in the family Beggiatoaceae, namely, 'Candidatus Albibeggiatoa psychrophila' gen. nov., sp. nov., thus providing the revised taxonomic status of the candidate genus 'BB20'. Analysis of 16S rRNA gene homology allowed us to identify MAG WS_Bin1 as the only currently described species of the genus 'Candidatus Parabeggiatoa', namely, 'Candidatus Parabeggiatoa communis', and consequently assign the candidate genus 'UBA10656', including four new species, to the genus 'Ca. Parabeggiatoa'. Using comparative whole-genome analysis of the members of the genera 'Candidatus Albibeggiatoa' and 'Ca. Parabeggiatoa', we expanded information on the central pathways of carbon, sulfur and nitrogen metabolism in the family Beggiatoaceae.


Sujet(s)
Phylogenèse , Soufre , Soufre/métabolisme , Métagénome , ARN ribosomique 16S/génétique , Génome bactérien , Eau de mer/microbiologie
8.
Acta Crystallogr D Struct Biol ; 80(Pt 6): 451-463, 2024 Jun 01.
Article de Anglais | MEDLINE | ID: mdl-38841886

RÉSUMÉ

Fragment-based drug design using X-ray crystallography is a powerful technique to enable the development of new lead compounds, or probe molecules, against biological targets. This study addresses the need to determine fragment binding orientations for low-occupancy fragments with incomplete electron density, an essential step before further development of the molecule. Halogen atoms play multiple roles in drug discovery due to their unique combination of electronegativity, steric effects and hydrophobic properties. Fragments incorporating halogen atoms serve as promising starting points in hit-to-lead development as they often establish halogen bonds with target proteins, potentially enhancing binding affinity and selectivity, as well as counteracting drug resistance. Here, the aim was to unambiguously identify the binding orientations of fragment hits for SARS-CoV-2 nonstructural protein 1 (nsp1) which contain a combination of sulfur and/or chlorine, bromine and iodine substituents. The binding orientations of carefully selected nsp1 analogue hits were focused on by employing their anomalous scattering combined with Pan-Dataset Density Analysis (PanDDA). Anomalous difference Fourier maps derived from the diffraction data collected at both standard and long-wavelength X-rays were compared. The discrepancies observed in the maps of iodine-containing fragments collected at different energies were attributed to site-specific radiation-damage stemming from the strong X-ray absorption of I atoms, which is likely to cause cleavage of the C-I bond. A reliable and effective data-collection strategy to unambiguously determine the binding orientations of low-occupancy fragments containing sulfur and/or halogen atoms while mitigating radiation damage is presented.


Sujet(s)
Halogènes , SARS-CoV-2 , Soufre , Halogènes/composition chimique , Cristallographie aux rayons X/méthodes , Soufre/composition chimique , SARS-CoV-2/composition chimique , Protéines virales non structurales/composition chimique , Humains , Électrons , Modèles moléculaires , Conception de médicament , Liaison aux protéines , Sites de fixation , COVID-19
9.
J Environ Manage ; 363: 121336, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38850915

RÉSUMÉ

Sulfur-siderite autotrophic denitrification (SSAD) has been proved to solve the key problem of low nitrogen removal efficiency caused by the shortage of carbon source in constructed wetlands (CWs). In this study, five vertical flow constructed wetlands (VFCWs) were constructed with different Fe/S ratios (0/0, 0/1, 1/1, 2/1 and 1/2) to optimizing SSAD process, labeled S.0, S.1, S.2, S.3 and S.4. The results showed that the best NO3--N and TN removal rates were achieved with a Fe/S ratio of 2:1 (S.3), which were 96.26 ± 1.40% and 93.63 ± 3.12%, respectively. The abundance of denitrification genes (nirS, nirK and nosZ) in S.3 was significantly increased. Illumina high-throughput sequencing analysis indicated that the abundance and diversity of microorganisms involved in the "Sulfur-Iron-Nitrogen" cycle were enriched in S.3. The current study provided that the "Sulfur-Iron-Nitrogen" cycle in CWs was optimized by adjusting Fe/S ratio, and more types of denitrifying bacteria could be enriched, thereby enhancing nitrogen removal.


Sujet(s)
Dénitrification , Fer , Azote , Soufre , Zones humides , Azote/métabolisme , Soufre/métabolisme , Fer/métabolisme
10.
Proc Natl Acad Sci U S A ; 121(24): e2400711121, 2024 Jun 11.
Article de Anglais | MEDLINE | ID: mdl-38833476

RÉSUMÉ

Understanding how microbial lipidomes adapt to environmental and nutrient stress is crucial for comprehending microbial survival and functionality. Certain anaerobic bacteria can synthesize glycerolipids with ether/ester bonds, yet the complexities of their lipidome remodeling under varying physicochemical and nutritional conditions remain largely unexplored. In this study, we thoroughly examined the lipidome adaptations of Desulfatibacillum alkenivorans strain PF2803T, a mesophilic anaerobic sulfate-reducing bacterium known for its high proportions of alkylglycerol ether lipids in its membrane, under various cultivation conditions including temperature, pH, salinity, and ammonium and phosphorous concentrations. Employing an extensive analytical and computational lipidomic methodology, we identified an assemblage of nearly 400 distinct lipids, including a range of glycerol ether/ester lipids with various polar head groups. Information theory-based analysis revealed that temperature fluctuations and phosphate scarcity profoundly influenced the lipidome's composition, leading to an enhanced diversity and specificity of novel lipids. Notably, phosphorous limitation led to the biosynthesis of novel glucuronosylglycerols and sulfur-containing aminolipids, termed butyramide cysteine glycerols, featuring various ether/ester bonds. This suggests a novel adaptive strategy for anaerobic heterotrophs to thrive under phosphorus-depleted conditions, characterized by a diverse array of nitrogen- and sulfur-containing polar head groups, moving beyond a reliance on conventional nonphospholipid types.


Sujet(s)
Lipidomique , Azote , Phosphore , Soufre , Phosphore/métabolisme , Soufre/métabolisme , Azote/métabolisme , Adaptation physiologique , Sulfates/métabolisme , Bactéries anaérobies/métabolisme , Anaérobiose
11.
J Hazard Mater ; 474: 134832, 2024 Aug 05.
Article de Anglais | MEDLINE | ID: mdl-38852245

RÉSUMÉ

Acid mine drainage and sediments (AMD-Sed) contamination pose serious ecological and environmental problems. This study investigated the geochemical parameters and bacterial communities in the sediment layer (A) and buried soil layer (B) of desert grassland contaminated with AMD-Sed and compared them to an uncontaminated control soil layer (CK). The results showed that soil pH was significantly lower and iron, sulfur, and electroconductivity levels were significantly higher in the B layer compared to CK. A and B were dominated by Proteobacteria and Actinobacteriota, while CK was dominated by Firmicutes and Bacteroidota. The pH, Fe, S, and potentially toxic elements (PTEs) gradients were key influences on bacterial community variability, with AMD contamination characterization factors (pH, Fe, and S) explaining 48.6 % of bacterial community variation. A bacterial co-occurrence network analysis showed that AMD-Sed contamination significantly affected topological properties, reduced network complexity and stability, and increased the vulnerability of desert grassland soil ecosystems. In addition, AMD-Sed contamination reduced C/N-cycle functioning in B, but increased S-cycle functioning. The results highlight the effects of AMD-Sed contamination on soil bacterial communities and ecological functions in desert grassland and provide a reference basis for the management and restoration of desert grassland ecosystems in their later stages.


Sujet(s)
Bactéries , Climat désertique , Sédiments géologiques , Prairie , Mine , Microbiologie du sol , Polluants du sol , Sédiments géologiques/microbiologie , Sédiments géologiques/composition chimique , Polluants du sol/toxicité , Polluants du sol/analyse , Concentration en ions d'hydrogène , Sol/composition chimique , Soufre/analyse , Fer/analyse , Acides/analyse , Microbiote
12.
Sci Total Environ ; 944: 173961, 2024 Sep 20.
Article de Anglais | MEDLINE | ID: mdl-38876338

RÉSUMÉ

The sulfur (S) cycle is an important biogeochemical cycle with profound implications for both cellular- and ecosystem-level processes by diverse microorganisms. Mangrove sediments are a hotspot of biogeochemical cycling, especially for the S cycle with high concentrations of S compounds. Previous studies have mainly focused on some specific inorganic S cycling processes without paying specific attention to the overall S-cycling communities and processes as well as organic S metabolism. In this study, we comprehensively analyzed the distribution, ecological network and assembly mechanisms of S cycling microbial communities and their changes with sediment depths using metagenome sequencing data. The results showed that the abundance of gene families involved in sulfur oxidation, assimilatory sulfate reduction, and dimethylsulfoniopropionate (DMSP) cleavage and demethylation decreased with sediment depths, while those involved in S reduction and dimethyl sulfide (DMS) transformation showed an opposite trend. Specifically, glpE, responsible for converting S2O32- to SO32-, showed the highest abundance in the surface sediment and decreased with sediment depths; in contrast, high abundances of dmsA, responsible for converting dimethyl sulfoxide (DMSO) to DMS, were identified and increased with sediment depths. We identified Pseudomonas and Streptomyces as the main S-cycling microorganisms, while Thermococcus could play an import role in microbial network connections in the S-cycling microbial community. Our statistical analysis showed that both taxonomical and functional compositions were generally shaped by stochastic processes, while the functional composition of organic S metabolism showed a transition from stochastic to deterministic processes. This study provides a novel perspective of diversity distribution of S-cycling functions and taxa as well as their potential assembly mechanisms, which has important implications for maintaining mangrove ecosystem functions.


Sujet(s)
Sédiments géologiques , Microbiote , Soufre , Zones humides , Sédiments géologiques/microbiologie , Sédiments géologiques/composition chimique , Soufre/métabolisme , Bactéries/métabolisme , Bactéries/classification , Bactéries/génétique
13.
Water Res ; 259: 121795, 2024 Aug 01.
Article de Anglais | MEDLINE | ID: mdl-38889663

RÉSUMÉ

Biological desulfurization under haloalkaline conditions has been applied worldwide to remove hydrogen sulfide (H2S) from sour gas steams. The process relies on sulfide-oxidizing bacteria (SOB) to oxidize H2S to elemental sulfur (S8), which can then be recovered and reused. Recently, a dual-reactor biological desulfurization system was implemented where an anaerobic (sulfidic) bioreactor was incorporated as an addition to a micro-oxic bioreactor, allowing for higher S8 selectivity by limiting by-product formation. The highly sulfidic bioreactor environment enabled the SOB to remove (poly)sulfides (Sx2-) in the absence of oxygen, with Sx2- speculated as a main substrate in the removal pathway, thus making it vital to understand its role in the process. The SOB are influenced by the oxidation-reduction potential (ORP) set-point of the micro-oxic bioreactor as it is used to control the product of oxidation (S8 vs. SO42-), while the uptake of Sx2- by SOB has been qualitatively linked to pH. Therefore, to quantify these effects, this work determined the concentration and speciation of Sx2- in the biological desulfurization process under various pH values and ORP set-points. The total Sx2- concentrations in the sulfidic zone increased at elevated pH (8.9) compared to low pH (< 8.0), with on average 3.3 ± 1.0 mM-S more Sx2-. Chain lengths varied, with S72- only doubling in concentration while S52- increased 9 fold, which is in contrast with observations from abiotic systems. Changes to the ORP set-point of the micro-oxic reactor did not produce substantial changes in Sx2- concentration in the sulfidic zone. This illustrates that the reduction degree of the SOB in the micro-oxic bioreactor does not enhance their ability to interact with Sx2- in the sulfidic bioreactor. This increased understanding of how both pH and ORP affect changes in Sx2- concentration and chain length can lead to improved efficiency and design of the dual-reactor biological desulfurization process.


Sujet(s)
Bioréacteurs , Oxydoréduction , Sulfures , Soufre , Sulfures/composition chimique , Sulfures/métabolisme , Concentration en ions d'hydrogène , Sulfure d'hydrogène/métabolisme
14.
Gut Microbes ; 16(1): 2370634, 2024.
Article de Anglais | MEDLINE | ID: mdl-38935546

RÉSUMÉ

Diet is a key player in gut-liver axis. However, the effect of different dietary patterns on gut microbiota and liver functions remains unclear. Here, we used rodent standard chow and purified diet to mimic two common human dietary patterns: grain and plant-based diet and refined-food-based diet, respectively and explored their impacts on gut microbiota and liver. Gut microbiota experienced a great shift with notable increase in Desulfovibrio, gut bile acid (BA) levels elevated significantly, and liver inflammation was observed in mice fed with the purified diet. Liver inflammation and elevated gut BA levels also occurred in mice fed with the chow diet after receiving Desulfovibrio desulfuricans ATCC 29,577 (DSV). Restriction of sulfur-containing amino acids (SAAs) prevented liver injury mainly through higher hepatic antioxidant and detoxifying ability and reversed the elevated BA levels due to excess Desulfovibrio. Ex vivo fermentation of human fecal microbiota with primary BAs demonstrated that DSV enhanced production of secondary BAs. Higher concentration of both primary and secondary BAs were found in the gut of germ-free mice after receiving DSV. In conclusion, Restriction of SAAs in diet may become an effective dietary intervention to prevent liver injury associated with excess Desulfovibrio in the gut.


Sujet(s)
Desulfovibrio , Microbiome gastro-intestinal , Foie , Souris de lignée C57BL , Animaux , Microbiome gastro-intestinal/effets des médicaments et des substances chimiques , Souris , Foie/métabolisme , Humains , Desulfovibrio/métabolisme , Mâle , Acides et sels biliaires/métabolisme , Acides aminés/métabolisme , Régime alimentaire , Fèces/microbiologie , Fèces/composition chimique , Soufre/métabolisme , Acides aminés soufrés/métabolisme
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 320: 124603, 2024 Nov 05.
Article de Anglais | MEDLINE | ID: mdl-38878720

RÉSUMÉ

Iron-sulfur cluster conversion and nitrosyl modification are involved in regulating their functions and play critical roles in signaling for biological systems. Hereby, the photo-induced dynamic process of (Me4N)2[Fe2S2(NO)4] was monitored using time-resolved electron paramagnetic resonance (EPR) spectra, MS spectra and cellular imaging methods. Photo-irradiation and the solvent affect the reaction rates and products. Spectroscopic and kinetic studies have shown that the process involves at least three intermediates: spin-trapped NO free radical species with a gav at 2.040, and two other iron nitrosyl species, dinitrosyl iron units (DNICs) and mononitrosyl iron units (MNICs) with gav values at 2.031 and 2.024, respectively. Moreover, the [Fe2S2(NO)4]2- cluster could bind with ferritin and decompose gradually, and a binding state of dinitrosyl iron coordinated with Cys102 of the recombinant human heavy chain ferritin (rHuHF) was finally formed. This study provides insight into the photodynamic mechanism of nitrosyl iron - sulfur clusters to improve the understanding of physiological activity.


Sujet(s)
Fer , Humains , Spectroscopie de résonance de spin électronique , Fer/composition chimique , Fer/métabolisme , Oxydes d'azote/composition chimique , Oxydes d'azote/métabolisme , Liaison aux protéines , Cinétique , Ferrosulfoprotéines/métabolisme , Ferrosulfoprotéines/composition chimique , Soufre/composition chimique , Soufre/métabolisme , Ferritines/composition chimique , Ferritines/métabolisme , Lumière
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 320: 124534, 2024 Nov 05.
Article de Anglais | MEDLINE | ID: mdl-38878718

RÉSUMÉ

In this study, Gordonia sp. HS126-4N was employed for dibenzothiophene (DBT) biodesulfurization, tracked over 9 days using SERS. During the initial lag phase, no significant spectral changes were observed, but after 48 h, elevated metabolic activity was evident. At 72 h, maximal bacterial population correlated with peak spectrum variance, followed by stable spectral patterns. Despite 2-hydroxybiphenyl (2-HBP) induced enzyme suppression, DBT biodesulfurization persisted. PCA and PLS-DA analysis of the SERS spectra revealed distinctive features linked to both bacteria and DBT, showcasing successful desulfurization and bacterial growth stimulation. PLS-DA achieved a specificity of 95.5 %, sensitivity of 94.3 %, and AUC of 74 %, indicating excellent classification of bacteria exposed to DBT. SERS effectively tracked DBT biodesulfurization and bacterial metabolic changes, offering insights into biodesulfurization mechanisms and bacterial development phases. This study highlights SERS' utility in biodesulfurization research, including its use in promising advancements in the field.


Sujet(s)
Gordonia bacterium , Analyse spectrale Raman , Thiophènes , Thiophènes/métabolisme , Thiophènes/composition chimique , Analyse spectrale Raman/méthodes , Gordonia bacterium/métabolisme , Soufre/métabolisme , Soufre/composition chimique , Dépollution biologique de l'environnement
17.
Sci Total Environ ; 945: 173998, 2024 Oct 01.
Article de Anglais | MEDLINE | ID: mdl-38901575

RÉSUMÉ

Globally, power stations generate huge amounts of the hazardous waste heavy oil fly ash (HOFA), which is rich in Ni, V, Fe, S, and dumped into landfills. Thus, exploring new approaches for a safe recycling and sustainable management of HOFA is needed and of great environmental interest. The potential application of HOFA as an amendment to sandy soils has not been studied yet. This is the first research investigating the potentiality of using HOFA as a soil conditioner. To this end, we conducted a greenhouse experiment in order to investigate the impacts of HOFA addition (1.2, 2.4, 3.6 t ha-1) to sandy soil on the total and available content of nutrients (e.g., S, Fe, Mn, Cu, Zn) and toxic elements (TEs; e.g., Cd, Co, Cr, Ni, Pb, V) in the soil and their phytoextraction and translocation by lemongrass (Cymbopogon citratus) and common sage (Salvia officinalis). We also assessed the impact of humic acid (HA) foliar application (50 and 100 l ha-1) on the growth and elements accumulation by the two plants. The studied HOFA was acidic and highly enriched in S (43,268.0), V (3,527.0), Ni (1774.0), and Fe (15,159.0) (units in mg kg-1). The X-ray absorption near edge structure (XANES) data showed that V in HOFA was composed primarily of V(IV) sorbed onto goethite, V(V) sorbed onto humic substances, in the forms of V2O3, and VCl4. Addition of the lower doses of HOFA (1.2 and 2.4 t ha-1) did not change significantly soil pH, salinity, and the total and available elements content compared to the unamended soil. Although the elements content in the 3.6 t ha-1 HOFA-treated soil was significantly higher than the untreated, the total content of all elements (except for Ni) was lower than the maximum allowable concentrations in soils. HOFA addition, particularly in the highest dose (3.6 t ha-1), decreased significantly the growth and biomass of both plants. Common sage accumulated more elements than lemongrass; however, the elements content in the plants was lower than the critical concentrations for sensitive plants. The foliar application of humic acid enhanced significantly the plant growth and increased their tolerance to the HOFA-induced stress. We conclude that the addition of HOFA up to 2.4 t ha-1 in a single application as amendment to sandy soils is not likely to create any TE toxicity problems to plants, particularly if combined with a foliar application of humic acid; however, repeated additions of HOFA may induce toxicity. These findings should be verified under field conditions.


Sujet(s)
Cendre de charbon , Substances humiques , Polluants du sol , Sol , Polluants du sol/analyse , Sol/composition chimique , Cymbopogon , Engrais , Soufre , Métaux lourds/analyse
18.
Biodegradation ; 35(5): 565-582, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38844743

RÉSUMÉ

A novel coupling process to replace the traditional multi-stage anammox process-sulfur autotrophic denitrification (SAD) coupled anaerobic ammonium oxidation (anammox) system was designed, which solved problems of nitrate produced in anammox process and low nitrate conversion rate caused by nitrite accumulation in SAD process. Different filter structures (SAD filter and anammox granular sludge) were investigated to further explore the excellent performance of the novel integrated reactor. The results of sequential batch experiments indicated that nitrite accumulation occurred during SAD, which inhibited the conversion of nitrate to dinitrogen gas. When SAD filter and anammox granular sludge were added to packed bed reactor simultaneously, the nitrate removal rate increased by 37.21% and effluent nitrite concentration decreased by 100% compared to that achieved using SAD. The stratified filter structure solved groove flow. Different proportion influence of SAD filter and anammox granular sludge on the stratified filter structure was evaluated. More suitable ratio of SAD filter to anammox granular sludge was 2:1. Proteobacteria (57.26%), Bacteroidetes (20.12%) and Chloroflexi (9.95%) were the main phyla. The dominant genera of denitrification functional bacteria were Thiobacillus (39.80%), Chlorobaculum (3.99%), norank_f_PHOs-HE36 (2.90%) and Ignavibacterium (2.64%). The dominant genus of anammox bacterium was Candidatus_Kuenenia (3.05%).


Sujet(s)
Processus autotrophes , Bioréacteurs , Dénitrification , Oxydoréduction , Bioréacteurs/microbiologie , Soufre/métabolisme , Eaux d'égout/microbiologie , Nitrates/métabolisme , Anaérobiose , Bactéries/métabolisme , Nitrites/métabolisme , Composés d'ammonium/métabolisme , Élimination des déchets liquides/méthodes
19.
Biosens Bioelectron ; 261: 116473, 2024 Oct 01.
Article de Anglais | MEDLINE | ID: mdl-38878701

RÉSUMÉ

Sensitive monitoring of luteinizing hormone (LH), a glycoprotein that regulates the synthesis of regulatory steroid hormones, can facilitate the diagnosis of various reproductive diseases. In this work, a new and highly catalytic Sulfur-doped and bimetal-coordinated CoFe(CN)5NO (denoted as S-CoFe(CN)5NO) nanoparticles are synthesized. Such material is further used to construct high performance sensing interface and coupled with primer exchange reaction (PER) and hybridization chain reaction (HCR) amplification cascades for sensitive electrochemical aptamer-based LH assay. Target LH molecules bind aptamer sequences in DNA duplex probes to liberate ssDNA strands, which initiate subsequent PER/HCR amplification cascades for the capture of many ferrocene (Fc)-tagged DNAs on sensing interface. S-CoFe(CN)5NO subsequently leads to catalytic oxidation of these Fc tags for yielding substantially magnified currents for realizing ultrasensitive assay of LH with the detection limit of 0.69 pM in range from 5 pM to 10 nM. Owing to the high specificity of aptamer, such sensor has high selectivity and can achieve low levels of LH assay in diluted serum samples. With the successful demonstration for detecting trace LH, such sensor can be easily extended as a universal aptamer-based electrochemical sensing method for monitoring various target analytes in the biomedical and biological fields.


Sujet(s)
Aptamères nucléotidiques , Techniques de biocapteur , Techniques électrochimiques , Limite de détection , Hormone lutéinisante , Aptamères nucléotidiques/composition chimique , Techniques de biocapteur/méthodes , Humains , Techniques électrochimiques/méthodes , Hormone lutéinisante/sang , Hormone lutéinisante/composition chimique , Catalyse , Soufre/composition chimique , Nanoparticules métalliques/composition chimique , Cobalt/composition chimique , Hybridation d'acides nucléiques , Nanoparticules/composition chimique , Composés du fer II/composition chimique
20.
Anal Methods ; 16(26): 4409-4414, 2024 Jul 04.
Article de Anglais | MEDLINE | ID: mdl-38904209

RÉSUMÉ

The detection of anions using carbon dots (CDs) has received less attention compared to cations. Therefore, the present study aimed to develop a fluorescence sensor based on carbon dots (CDs) capable of detecting S2- in real water samples. The CDs were successfully prepared from the residues of a traditional Chinese herb, Gardenia, which emitted green photoluminescence (PL) under ultraviolet light irradiation. The as-prepared CDs were quasi-spherical in shape and ranged in size from 10 to 30 nm. Different detailed analyses proved that the CDs had good morphology, various functional groups, high water solubility, great optical features, and excellent stability under diverse environmental conditions. The ion detection showed that only Ag+ had the strongest fluorescence quenching effect on the CDs, however, the addition of S2- could recover their fluorescence. Based on these results, an "off-on" fluorescence sensor was achieved to selectively detect the concentration of S2- in real water samples with a limit of detection (LOD) of 39 µM, which further expanded the application of residues from traditional Chinese herbal medicine.


Sujet(s)
Carbone , Gardenia , Boîtes quantiques , Soufre , Carbone/composition chimique , Soufre/composition chimique , Boîtes quantiques/composition chimique , Gardenia/composition chimique , Spectrométrie de fluorescence/méthodes , Limite de détection , Polluants chimiques de l'eau/analyse
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