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1.
Int J Mol Sci ; 25(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-39000305

RESUMO

Nitrosyl iron complexes are remarkably multifactorial pharmacological agents. These compounds have been proven to be particularly effective in treating cardiovascular and oncological diseases. We evaluated and compared the antioxidant activity of tetranitrosyl iron complexes (TNICs) with thiosulfate ligands and dinitrosyl iron complexes (DNICs) with glutathione (DNIC-GS) or phosphate (DNIC-PO4-) ligands in hemoglobin-containing systems. The studied effects included the production of free radical intermediates during hemoglobin (Hb) oxidation by tert-butyl hydroperoxide, oxidative modification of Hb, and antioxidant properties of nitrosyl iron complexes. Measuring luminol chemiluminescence revealed that the antioxidant effect of TNICs was higher compared to DNIC-PO4-. DNIC-GS either did not exhibit antioxidant activity or exerted prooxidant effects at certain concentrations, which might have resulted from thiyl radical formation. TNICs and DNIC-PO4- efficiently protected the Hb heme group from decomposition by organic hydroperoxides. DNIC-GS did not exert any protective effects on the heme group; however, it abolished oxoferrylHb generation. TNICs inhibited the formation of Hb multimeric forms more efficiently than DNICs. Thus, TNICs had more pronounced antioxidant activity than DNICs in Hb-containing systems.


Assuntos
Antioxidantes , Hemoglobinas , Ferro , Fosfatos , Tiossulfatos , Tiossulfatos/farmacologia , Tiossulfatos/química , Hemoglobinas/metabolismo , Hemoglobinas/química , Ferro/metabolismo , Ferro/química , Fosfatos/química , Fosfatos/metabolismo , Ligantes , Antioxidantes/farmacologia , Compostos de Sulfidrila/química , Compostos de Sulfidrila/metabolismo , Oxirredução/efeitos dos fármacos , Óxidos de Nitrogênio/química , Óxidos de Nitrogênio/farmacologia , Óxidos de Nitrogênio/metabolismo , Glutationa/metabolismo , Animais
2.
Sci Total Environ ; 945: 174042, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38908573

RESUMO

Selecting an appropriate electron donor to enhance nitrogen removal for treating low C/N wastewater in ecological floating beds (EFBs) is controversy. In this study, a systematic and comprehensive evaluation of sodium acetate (EFB-C), sodium thiosulfate (EFB-S) and iron scraps (EFB-Fe) was performed in a 2-year experiment on long-term viability including nitrogen removal and greenhouse gas emissions associated with key molecular biological mechanisms. The results showed that EFB-C (43-85 %) and EFB-S (40-88 %) exhibited superior total nitrogen (TN) removal. Temperature and hydraulic retention time (HRT) have significant impacts on TN removal of EFB-Fe, however, it could reach 86 % under high temperature (30-35 °C) and a long HRT (3 days), and it has lowest N2O (0-6.2 mg m-2 d-1) and CH4 (0-5.3 mg m-2 d-1) fluxes. Microbial network analysis revealed that the microbes changed from competing to cooperating after adding electron donors. A higher abundance of anammox genera was enriched in EFB-Fe. The Mantel's test and structural equation model provided proof of the differences, which showed that acetate and thiosulfate were similar, whereas Fe0 was different in the nitrogen removal mechanism. Molecular biology analyses further verified that heterotrophic, autotrophic, and mixotrophic coupled with anammox were the main TN removal pathways for EFB-C, EFB-S, and EFB-Fe, respectively. These findings provide a better understanding of the biological mechanisms for selecting appropriate electron donors for treating low C/N wastewater.


Assuntos
Gases de Efeito Estufa , Nitrogênio , Tiossulfatos , Eliminação de Resíduos Líquidos , Águas Residuárias , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Gases de Efeito Estufa/análise , Ferro , Acetatos , Carbono
3.
Int J Biol Macromol ; 274(Pt 2): 133481, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38942407

RESUMO

Thiosulfate has been considered as a more environmentally-friendly alternative to cyanide salts for the extraction of gold from gold ores and the development of affordable, green and efficient adsorbents for the isolation of gold-thiosulfate complex (Au(S2O3)23-) from the leaching solution remains a significant challenge. To address this issue, chitosan, a natural macromolecule, was selected as a carrier and chemically modified with ionic liquids. The ionic liquids modified chitosan showed greater adsorption capacity towards Au(S2O3)23- compared with pristine chitosan. The adsorption of Au(S2O3)23- on ionic liquid modified chitosan followed Freundlich isotherm and pseudo-second order kinetic models, involving an anion-exchange mechanism with liquid film diffusion as the rate-limiting step. The chitosan modified with butylimidazolium-based ionic liquid had an adsorption capacity of 5.0 mg g-1 for gold (10 mg L-1 of gold, pH 6, 2 g L-1 of adsorbent dosage), outperforming other reported adsorbents. The ionic liquid modified chitosan showed a high adsorption efficiency of up to 96.7 % for Au(S2O3)23- in an actual thiosulfate leaching solution with a desorption efficiency of 98.4 %, suggesting that the ionic liquid modified chitosan has the potential to be a eco-friendly, biocompatible and effective adsorbent for the recovery of Au(S2O3)23-.


Assuntos
Quitosana , Ouro , Líquidos Iônicos , Quitosana/química , Líquidos Iônicos/química , Adsorção , Ouro/química , Cinética , Concentração de Íons de Hidrogênio , Química Verde , Tiossulfatos/química
4.
Nitric Oxide ; 149: 67-74, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38897561

RESUMO

Sodium thiosulfate has been used for decades in the treatment of calciphylaxis and cyanide detoxification, and has recently shown initial therapeutic promise in critical diseases such as neuronal ischemia, diabetes mellitus, heart failure and acute lung injury. However, the precise mechanism of sodium thiosulfate remains incompletely defined and sometimes contradictory. Although sodium thiosulfate has been widely accepted as a donor of hydrogen sulfide (H2S), emerging findings suggest that it is the executive signaling molecule for H2S and that its effects may not be dependent on H2S. This article presents an overview of the current understanding of sodium thiosulfate, including its synthesis, biological characteristics, and clinical applications of sodium thiosulfate, as well as the underlying mechanisms in vivo. We also discussed the interplay of sodium thiosulfate and H2S. Our review highlights sodium thiosulfate as a key player in sulfide signaling with the broad clinical potential for the future.


Assuntos
Sulfeto de Hidrogênio , Transdução de Sinais , Tiossulfatos , Tiossulfatos/química , Sulfeto de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/química , Humanos , Animais , Transdução de Sinais/efeitos dos fármacos
5.
Environ Sci Pollut Res Int ; 31(26): 38298-38309, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38797755

RESUMO

Thiosulfate gold leaching is one of the most promising green cyanide-free gold extraction processes; however, the difficulty of recovering Au(I) from the leaching system hinders its further development. This study prepared aminoguanidine-functionalized microspheres (AGMs) via a one-step reaction involving nucleophilic substitution between aminoguanidine hydrochloride and chloromethylated polystyrene microspheres and used AGMs to adsorb Au(I) from thiosulfate solutions. Scanning electron microscopy, Brunauer-Emmett-Teller analysis, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy were used to analyze the structure and properties of AGMs. Experiments were designed to investigate the effects of pH, temperature, initial Au(I), and thiosulfate concentrations on the gold adsorption performance of AGMs. Results demonstrated that AGMs can efficiently adsorb Au(I) from thiosulfate solutions in a wide pH range. The adsorption process conforms to the pseudo-second-order kinetic model and Langmuir isotherm model, with a maximum capacity of 22.03 kg/t. Acidic thiourea is an effective desorbent, and after four adsorption-desorption cycles, the adsorption rate of Au(I) by AGMs is 78.63%, which shows AGMs have good cyclic application potential. Based on the results of characterization, experiments, and density functional theory calculations, the mechanism for the adsorption of [Au(S2O3)2]3- on AGMs involves anion exchange. Importantly, AGMs exhibited satisfactory adsorption property for Au(I) in practical Cu2+-NH3(en)-S2O32- systems. This study provided experimental reference for the recovery of Au(I) from thiosulfate solution.


Assuntos
Ouro , Guanidinas , Tiossulfatos , Tiossulfatos/química , Adsorção , Guanidinas/química , Ouro/química , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Concentração de Íons de Hidrogênio , Microesferas
6.
J Clin Oncol ; 42(18): 2219-2232, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38648563

RESUMO

PURPOSE: Hearing loss occurs in 50%-70% of children treated with cisplatin. Scientific efforts have led to the recent approval of a pediatric formula of intravenous sodium thiosulfate (STS) for otoprotection by the US Food and Drug Administration, the European Medicines Agency, and the Medicines and Health Regulatory Authority in the United Kingdom. To inform stakeholders regarding the clinical utility of STS, the current review summarizes available literature on the efficacy, pharmacokinetics (PK), and safety of systemic STS to minimize cisplatin-induced hearing loss (CIHL). DESIGN: A comprehensive narrative review is presented. RESULTS: Thirty-one articles were summarized. Overall, systemic STS effectively reduces CIHL in the preclinical and controlled clinical study settings, in both adults and children with cancer. The extent of CIHL reduction depends on the timing and dosing of STS in relation to cisplatin. Both preclinical and clinical data suggest that systemic STS may affect plasma platinum levels, but studies are inconclusive. Delayed systemic administration of STS, at 6 hours after the cisplatin infusion, does not affect cisplatin-induced inhibition of tumor growth or cellular cytotoxicity in the preclinical setting, nor affect cisplatin efficacy and survival in children with localized disease in the clinical setting. CONCLUSION: Systemic administration of STS effectively reduces the development and degree of CIHL in both the preclinical and clinical settings. More studies are needed on the PK of STS and cisplatin drug combinations, the efficacy and safety of STS in patients with disseminated disease, and the ability of STS to prevent further deterioration of pre-established hearing loss.


Assuntos
Antineoplásicos , Cisplatino , Perda Auditiva , Neoplasias , Tiossulfatos , Humanos , Tiossulfatos/uso terapêutico , Tiossulfatos/farmacocinética , Tiossulfatos/administração & dosagem , Neoplasias/tratamento farmacológico , Cisplatino/uso terapêutico , Cisplatino/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/farmacocinética , Antineoplásicos/farmacocinética , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Antineoplásicos/administração & dosagem , Perda Auditiva/induzido quimicamente , Perda Auditiva/prevenção & controle , Criança
7.
FEMS Microbiol Ecol ; 100(5)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38573825

RESUMO

Ferriphaselus amnicola GF-20 is the first Fe-oxidizing bacterium isolated from the continental subsurface. It was isolated from groundwater circulating at 20 m depth in the fractured-rock catchment observatory of Guidel-Ploemeur (France). Strain GF-20 is a neutrophilic, iron- and thiosulfate-oxidizer and grows autotrophically. The strain shows a preference for low oxygen concentrations, which suggests an adaptation to the limiting oxygen conditions of the subsurface. It produces extracellular stalks and dreads when grown with Fe(II) but does not secrete any structure when grown with thiosulfate. Phylogenetic analyses and genome comparisons revealed that strain GF-20 is affiliated with the species F. amnicola and is strikingly similar to F. amnicola strain OYT1, which was isolated from a groundwater seep in Japan. Based on the phenotypic and phylogenetic characteristics, we propose that GF-20 represents a new strain within the species F. amnicola.


Assuntos
Água Subterrânea , Ferro , Oxirredução , Filogenia , RNA Ribossômico 16S , Tiossulfatos , Água Subterrânea/microbiologia , Tiossulfatos/metabolismo , Ferro/metabolismo , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , França , Genoma Bacteriano , Análise de Sequência de DNA , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Bacteroidetes/classificação , Bacteroidetes/metabolismo
8.
Bioresour Technol ; 401: 130747, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38677382

RESUMO

Sulfur-driven autotrophic denitrification (SdAD) is a promising nitrogen removing process, but its applications were generally constrained by conventional electron donors (i.e., thiosulfate (Na2S2O3)) with high valence and limited bioavailability. Herein, an immobilized electron donor by loading elemental sulfur on the surface of polyurethane foam (PFSF) was developed, and its feasibility for SdAD was investigated. The denitrification efficiency of PFSF was 97.3%, higher than that of Na2S2O3 (91.1%). Functional microorganisms (i.e., Thiobacillus and Sulfurimonas) and their metabolic activities (i.e., nir and nor) were substantially enhanced by PFSF. PFSF resulted in the enrichment of sulfate-reducing bacteria, which can reduce sulfate (SO42-). It attenuated the inhibitory effect of SO42-, whereas the generated product (hydrogen sulfide) also served as an electron donor for SdAD. According to the economic evaluation, PFSF exhibited strong market potential. This study proposes an efficient and low-cost immobilized electron donor for SdAD and provides theoretical support to its practical applications.


Assuntos
Processos Autotróficos , Desnitrificação , Nitrogênio , Enxofre , Enxofre/metabolismo , Enxofre/química , Elétrons , Thiobacillus/metabolismo , Poliuretanos/química , Sulfatos/metabolismo , Bactérias/metabolismo , Tiossulfatos/química , Tiossulfatos/farmacologia
9.
PLoS Biol ; 22(4): e3002601, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38656967

RESUMO

Uptake of thiosulfate ions as an inorganic sulfur source from the environment is important for bacterial sulfur assimilation. Recently, a selective thiosulfate uptake pathway involving a membrane protein YeeE (TsuA) in Escherichia coli was characterized. YeeE-like proteins are conserved in some bacteria, archaea, and eukaryotes. However, the precise function of YeeE, along with its potential partner protein in the thiosulfate ion uptake pathway, remained unclear. Here, we assessed selective thiosulfate transport via Spirochaeta thermophila YeeE in vitro and characterized E. coli YeeD (TsuB) as an adjacent and essential protein for YeeE-mediated thiosulfate uptake in vivo. We further showed that S. thermophila YeeD possesses thiosulfate decomposition activity and that a conserved cysteine in YeeD was modified to several forms in the presence of thiosulfate. Finally, the crystal structures of S. thermophila YeeE-YeeD fusion proteins at 3.34-Å and 2.60-Å resolutions revealed their interactions. The association was evaluated by a binding assay using purified S. thermophila YeeE and YeeD. Based on these results, a model of the sophisticated uptake of thiosulfate ions by YeeE and YeeD is proposed.


Assuntos
Escherichia coli , Sulfurtransferases , Tiossulfatos , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Transporte Biológico/genética , Cristalografia por Raios X , Cisteína/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Ligação Proteica , Sulfurtransferases/genética , Sulfurtransferases/metabolismo , Tiossulfatos/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo
11.
Bioresour Technol ; 398: 130548, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38458263

RESUMO

Anaerobic fermentation (AF) has been identified as a promising method of transforming waste activated sludge (WAS) into high-value products (e.g., short-chain fatty acids (SCFAs)). This study developed thiosulfate/FeCl3 pre-treatment and investigated the effects of different thiosulfate/FeCl3 ratios (S:Fe = 3:1, 3:2, 1:1, 3:4 and 3:5) on SCFA production and sulfur transformation during the AF of WAS. At a S:Fe ratio of 1:1, the maximal SCFA yield (933.3 mg COD/L) and efficient H2S removal (96.5 %) were obtained. S:Fe ratios ≤ 1:1 not only benefited hydrolysis and acidification but largely mitigated H2S generation. These results were supported by the enriched acidogens and reduced sulfur-reducing bacteria (SRB). Molecular ecological network analysis further revealed that the keystone taxon (g_Saccharimonadales) was found in S:Fe = 1:1, together with reductions in associations among methanogens, acidogens and SRB. This work provides a strategy for enhancing high-value product recovery from WAS and minimising H2S emissions.


Assuntos
Cloretos , Compostos Férricos , Microbiota , Esgotos , Fermentação , Esgotos/microbiologia , Anaerobiose , Tiossulfatos , Ácidos Graxos Voláteis , Concentração de Íons de Hidrogênio
12.
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
13.
Ecotoxicol Environ Saf ; 274: 116210, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38479311

RESUMO

Thiosulfate influences the bioreduction and migration transformation of arsenic (As) and iron (Fe) in groundwater environments. The aim of this study was to investigate the impact of microbially-mediated sulfur cycling on the bioreduction and interaction of As and Fe. Microcosm experiments were conducted, including bioreduction of thiosulfate, As(V), and Fe(III) by Citrobacter sp. JH012-1, as well as the influence of thiosulfate input at different initial arsenate concentrations on the bioreduction of As(V) and Fe(III). The results demonstrate that Citrobacter sp. JH012-1 exhibited strong reduction capabilities for thiosulfate, As(V), and Fe(III). Improving thiosulfate level promoted the bioreduction of Fe(III) and As(V). When 0, 0.1, 0.5, and 1 mM thiosulfate were added, Fe(III) was completely reduced within 9 days, 3 days, 1 day, and 0.5 days, simultaneously, 72.8%, 82.2%, 85.5%, and 90.0% of As(V) were reduced, respectively. The products of As(III) binding with sulfide are controlled by the ratio of As-S. When the initial arsenate concentration was 0.025 mM, the addition of thiosulfate resulted in the accumulation of soluble thioarsenite. However, when the initial arsenate level increased to 1 mM, precipitates of orpiment or realgar were formed. In the presence of both arsenic and iron, As(V) significantly inhibits the bioreduction of Fe(III). Under the concentrations of 0, 0.025, and 1 mM As(V), the reduction rates of Fe(III) were 100%, 91%, and 83%, respectively. In this scenario, the sulfide produced by thiosulfate reduction tends to bind with Fe(II) rather than As(III). Therefore, the competition of arsenic-iron and thiosulfate concentration should be considered to study the impact of thiosulfate on arsenic and iron migration and transformation in groundwater.


Assuntos
Arsênio , Água Subterrânea , Ferro/análise , Arsênio/metabolismo , Arseniatos , Tiossulfatos , Oxirredução , Sulfetos , Compostos Férricos/metabolismo
14.
Sci Total Environ ; 923: 171457, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38442751

RESUMO

Bacteria have evolved a variety of strategies to defend themselves against cadmium toxicity, however, the specific mechanisms involved in the enhancement of bacterial cadmium resistance by sulfur sources are unclear. In this study, a novel cadmium (Cd)-tolerant bacterium, Stenotrophomonas geniculata G303, was isolated from activated sludge. The growth of strain G303 under diverse Cd concentrations was investigated, and the minimum inhibitory concentration of Cd was found to be 1 mM. Strain G303 effectively remove 94.7 % of Cd after 96 h of culture. Extracellular CdS was detected using multiple methods, with the CdS formed being aggregated in the biofilm. The addition of cysteine and thiosulfate to the medium significantly enhanced the Cd resistance and removal capacity of strain G303. Integrated genomic and proteomic analyses revealed that heavy metal transporters cooperate to resist Cd stress. Cysteine and thiosulfate improved Cd tolerance in strain G303 by upregulating nitrogen and energy metabolism. Proteins associated with nitrate reduction likely played a pivotal role in cysteine and thiosulfate metabolism. Notably, cysteine synthase and the SUF system played crucial roles in CdS formation. This study systematically explored the impact of cysteine and thiosulfate on the Cd resistance of strain G303, deepening our understanding of the microbial response mechanism to heavy metals.


Assuntos
Cádmio , Metais Pesados , Cádmio/toxicidade , Cádmio/metabolismo , Cisteína , Tiossulfatos , Proteômica
15.
Eur J Prosthodont Restor Dent ; 32(2): 194-202, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38299347

RESUMO

To evaluate the effect of calcium hydroxide (CH), sodium ascorbate (SA) and sodium thiosulfate (ST) filling the pulp chamber on color stability and longevity of teeth after internal bleaching. Crowns of bovine incisors were submitted to internal bleaching and divided into groups according the material used in the pulp chamber: Control, CH, SA, ST. Each group was divided into two subgroups according to the time to perform restorative procedures (7 or 15 days). Color measurement was performed with a spectrophotometer at nine periods. The darkening (ΔE) values were calculated. The Mann-Whitney test was used to statistically analyze the data (p ⟨ 0.05). After bleaching, ΔE values were higher than 3.5, showing that the procedure was effective. After 24 hours, no difference was observed between groups. After 7 days, SA showed higher ΔE than the control group (p ⟨ 0.05). CH and TS did not differ from the control group. In restorations performed after 7/15 days, SA group showed higher values of darkening after 1 and 4 months than the control group (p ⟨ 0.05). SA induced perceptible darkening after bleaching and should not be used to fill the pulp chamber. ST and CH show color stability and longevity after 12 months.


Assuntos
Antioxidantes , Hidróxido de Cálcio , Cavidade Pulpar , Clareadores Dentários , Clareamento Dental , Animais , Bovinos , Antioxidantes/farmacologia , Clareadores Dentários/farmacologia , Espectrofotometria , Ácido Ascórbico/farmacologia , Tiossulfatos/farmacologia , Descoloração de Dente , Cor
16.
mBio ; 15(4): e0000424, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38417116

RESUMO

Chloroflexota bacteria are abundant and globally distributed in various deep-sea ecosystems. It has been reported based on metagenomics data that two deep-sea Chloroflexota lineages (the SAR202 group and Dehalococcoidia class) have the potential to drive sulfur cycling. However, the absence of cultured Chloroflexota representatives is a significant bottleneck toward understanding their contribution to the deep-sea sulfur cycling. In this study, we find that Phototrophicus methaneseepsis ZRK33 isolated from deep-sea sediment has a heterotrophic lifestyle and can assimilate sulfate and thiosulfate. Using combined physiological, genomic, proteomic, and in situ transcriptomic methods, we find that strain ZRK33 can perform assimilatory sulfate reduction in both laboratory and deep-sea conditions. Metabolism of sulfate or thiosulfate by strain ZRK33 significantly promotes the transport and degradation of various macromolecules and thereby stimulates the energy production. In addition, metagenomic results show that genes associated with assimilatory and dissimilatory sulfate reduction are ubiquitously distributed in the metagenome-assembled genomes of Chloroflexota members derived from deep-sea sediments. Metatranscriptomic results also show that the expression levels of related genes are upregulated, strongly suggesting that Chloroflexota bacteria may play undocumented roles in deep-sea sulfur cycling. IMPORTANCE: The cycling of sulfur is one of Earth's major biogeochemical processes and is closely related to the energy metabolism of microorganisms living in the deep-sea cold seep and hydrothermal vents. To date, some of the members of Chloroflexota are proposed to play a previously unrecognized role in sulfur cycling. However, the sulfur metabolic characteristics of deep-sea Chloroflexota bacteria have never been reported, and remain to be verified in cultured deep-sea representatives. Here, we show that the deep-sea Chloroflexota bacterium ZRK33 can perform sulfate assimilation in both laboratory and deep-sea conditions, which expands our knowledge of the sulfur metabolic potential of deep-sea Chloroflexota bacteria. We also show that the genes associated with assimilatory and dissimilatory sulfate reduction ubiquitously distribute in the deep-sea Chloroflexota members, providing hints to the roles of Chloroflexota bacteria in deep-sea sulfur biogeochemical cycling.


Assuntos
Chloroflexi , Microbiota , Proteômica , Multiômica , Tiossulfatos/metabolismo , Oxirredução , Bactérias/genética , Chloroflexi/genética , Enxofre/metabolismo , Filogenia
17.
Water Res ; 253: 121264, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38335842

RESUMO

Quenching is an important step to terminate disinfection during preparation of disinfected water samples for the analysis of disinfection byproducts (DBPs). However, an incomplete quenching might result in continued reactions of residual chlorine, whereas an excessive quenching might decompose target DBPs. Therefore, an adequate quenching to achieve simultaneous disinfection termination and DBP preservation is of particular importance. In this study, the two-stage reaction kinetics of chlorine and three commonly used quenching agents (i.e., ascorbic acid, sodium thiosulfate, and sodium sulfite) were determined. Stopping quenching during the first stage prevented interactions of residual chlorine with natural organic matter. Complete quenching was achieved by minimizing the quenching time for ascorbic acid and sodium sulfite, while limiting the quenching time to less than 3 min for sodium thiosulfate. At the optimized quenching times, the molar ratios (MRs) of quenching agent to chlorine were 1.05, 1.10, and 0.75 for ascorbic acid, sodium sulfite, and sodium thiosulfate, respectively. The destructive effects of the three quenching agents on total organic halogen (TOX) followed the rank order of ascorbic acid (33.7-64.8 %) < sodium sulfite (41.6-72.8 %) < sodium thiosulfate (43.3-73.2 %), and the destructive effects on aliphatic DBPs also followed the rank order of ascorbic acid (29.5-44.5 %) < sodium sulfite (34.9-51.9 %) < sodium thiosulfate (46.9-53.2 %). For total organic chlorine (TOCl) and aliphatic DBPs, the quenching behavior itself had more significant destructive effect than the quenching agent type/dose and quenching time, but for total organic bromine (TOBr), the destructive effect caused by quenching agent type/dose and quenching time was more significant. High-dose, long-duration quenching enhanced the reduction of TOX, but had little effect on aliphatic DBPs. Additionally, the three quenching agents reduced the levels of halophenols (except for tribromophenol), while maintained or increased the levels of tribromophenol, halobenzoic/salicylic acids, and halobenzaldehydes/salicylaldehydes. To achieve adequate quenching for overall DBP analysis in chlorinated water samples, it is recommended to use ascorbic acid at a quenching agent-to-chlorine MR of 1.0 for a quenching time of < 0.5 h.


Assuntos
Desinfetantes , Água Potável , Sulfitos , Tiossulfatos , Poluentes Químicos da Água , Purificação da Água , Água Potável/análise , Cloro/análise , Desinfetantes/análise , Halogênios/análise , Desinfecção , Cloretos , Ácido Ascórbico/análise , Poluentes Químicos da Água/análise , Halogenação
18.
Int J Mol Sci ; 25(4)2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38396887

RESUMO

Kidney transplantation is preferred for end-stage renal disease. The current gold standard for kidney preservation is static cold storage (SCS) at 4 °C. However, SCS contributes to renal graft damage through ischemia-reperfusion injury (IRI). We previously reported renal graft protection after SCS with a hydrogen sulfide donor, sodium thiosulfate (STS), at 4 °C. Therefore, this study aims to investigate whether SCS at 10 °C with STS and Hemopure (blood substitute), will provide similar protection. Using in vitro model of IRI, we subjected rat renal proximal tubular epithelial cells to hypoxia-reoxygenation for 24 h at 10 °C with or without STS and measured cell viability. In vivo, we preserved 36 donor kidneys of Lewis rats for 24 h in a preservation solution at 10 °C supplemented with STS, Hemopure, or both followed by transplantation. Tissue damage and recipient graft function parameters, including serum creatinine, blood urea nitrogen, urine osmolality, and glomerular filtration rate (GFR), were evaluated. STS-treated proximal tubular epithelial cells exhibited enhanced viability at 10 °C compared with untreated control cells (p < 0.05). Also, STS and Hemopure improved renal graft function compared with control grafts (p < 0.05) in the early time period after the transplant, but long-term function did not reach significance. Overall, renal graft preservation at 10 °C with STS and Hemopure supplementation has the potential to enhance graft function and reduce kidney damage, suggesting a novel approach to reducing IRI and post-transplant complications.


Assuntos
Hemoglobinas , Transplante de Rim , Traumatismo por Reperfusão , Tiossulfatos , Ratos , Animais , Preservação de Órgãos , Sobrevivência de Enxerto , Ratos Endogâmicos Lew , Rim , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/prevenção & controle
19.
Eur J Surg Oncol ; 50(2): 107955, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38219699

RESUMO

BACKGROUND: Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC) is an effective treatment for peritoneal metastases. However, HIPEC with cisplatin is associated with renal toxicity. Sodium thiosulfate (ST) has been shown to prevent cisplatin-induced toxicity. METHODS: A retrospective, single-center analysis of patients treated curatively for peritoneal surface malignancy, who underwent cytoreductive surgery with cisplatin-based HIPEC between 2015 and 2020. Patients were categorized into three groups based on the management of cisplatin-induced renal toxicity: preoperative hyperhydration alone (PHH), preoperative hyperhydration with ST (PHH + ST), and ST alone. Renal function and complications, in terms of Acute (AKI) and chronic kidney injury (CKI), were monitored and analyzed during 3 postoperative months. RESULTS: This study included 220 consecutive patients. Mean serum creatinine levels were 95, 57 and 61 mmol/L, for PHH, PHH + ST and ST groups, respectively (p < 0.001). Glomerular Filtration Rate (GFR) were 96, 94 and 78 ml/min/1.73 m2, respectively (p < 0.001). AKI and CKI are respectively for PHH, PHH + ST and ST groups were 21 % (n = 46), 1 % (n = 2) and 0 % vs 19 % (n = 42), 0 % and 0 % (p < 0.001), for pairwise analysis did not show any difference between PHH + ST and ST alone combination, regarding nephrological outcomes. All patients were followed 3 months postoperatively. CONCLUSION: There is no need for preoperative hyperhydration when sodium-thiosulfate is used to prevent cisplatin-induced nephrotoxicity in patients undergoing cytoreductive surgery with HIPEC. These findings have implications for improving and simplifying the management of patients with peritoneal metastases undergoing HIPEC with cisplatin.


Assuntos
Injúria Renal Aguda , Antineoplásicos , Hipertermia Induzida , Neoplasias Peritoneais , Intoxicação por Água , Humanos , Cisplatino , Antineoplásicos/uso terapêutico , Tiossulfatos/uso terapêutico , Quimioterapia Intraperitoneal Hipertérmica/efeitos adversos , Estudos Retrospectivos , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/secundário , Intoxicação por Água/induzido quimicamente , Intoxicação por Água/complicações , Hipertermia Induzida/efeitos adversos , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/prevenção & controle , Procedimentos Cirúrgicos de Citorredução/efeitos adversos , Terapia Combinada , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Taxa de Sobrevida
20.
Bioresour Technol ; 395: 130331, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38224786

RESUMO

Sulfur-driven autotrophic denitrification (SAD) granular process has significant advantages in treating low-carbon/nitrogen wastewater; however, the slow growth rate of sulfur-oxidizing bacteria (SOB) results in a prolonged start-up duration. In this study, the thiosulfate-driven autotrophic denitrification (TAD) was successfully initiated by inoculating anaerobic granular sludge on Day 7. Additionally, the electron donor was successfully transferred to the cheaper elemental sulfur from Day 32 to Day 54 at the nitrogen loading rate of 176.2 g N m-3 d-1. During long term experiment, the granules maintained compact structures with the α-helix/(ß-sheet + random coil) of 29.5-40.1 %. Extracellular electron transfer (EET) pathway shifted from indirect to direct when electron donors were switched thiosulfate to elemental sulfur. Microbial analysis suggested that thiosulfate improved EET involving enzymes activity. Thiobacillus and Sulfurimonas were dominant in TAD, whereas Longilinea was enriched in elemental sulfur-driven autotrophic denitrification. Overall, this strategy achieved in-situ enrichment of SOB in granules, thereby shortening start-up process.


Assuntos
Microbiota , Tiossulfatos , Desnitrificação , Elétrons , Nitratos/metabolismo , Reatores Biológicos , Bactérias/metabolismo , Enxofre/metabolismo , Processos Autotróficos , Nitrogênio
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