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Hydrogen sulphide (H2S), a newly identified gasotransmitter, can be endogenously produced by cystathionine gamma-lyase (CSE) in the cardiovascular system. This study investigated the role of the CSE/H2S system on lipid overload-induced lipotoxicity and cardiac senescence. Lipid overload in rat cardiomyocyte cells (H9C2) promoted intracellular accumulation of lipid, oxidative stress, mitochondrial dysfunctions, lipid peroxidation and inhibited cell viability, all of which could be reversed by exogenously applied H2S. Further data revealed that H2S protected H9C2 cells from lipid overload-induced senescence by altering the expressions of lipid metabolism-related genes and inhibiting cellular acetyl-CoA and global protein acetylation. Enhancement of protein acetylation abolished the protective role of H2S on cardiac senescence. In vivo, knockout of the CSE gene strengthened cardiac lipid accumulation, protein acetylation, and cellular ageing in high fat diet-fed mice. Taken together, the CSE/H2S system is capable of maintaining lipid homeostasis and cellular senescence in heart cells under lipid overload. [ABSTRACT FROM AUTHOR]

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Hydrogen sulfide (H2S) as the third gasotransmitter could regulate many physiological processes such as growth and stress responses in plants. However, few studies focused on H2S affecting cell differentiation and secondary metabolism of suspension cells. In this study, we investigated the impact of sodium hydrogen sulfide (NaHS) doses (0, 0.5, 1.0, 3.0 mM) as H2S-donor at different time points on cell differentiation, antioxidant capacity, and accumulation of flavonoids (Fla) and terpene lactones (Lac) in Ginkgo biloba L. suspension cells. Results showed that distinct asymmetric division with a large and a small cell appeared in suspension cells under three NaHS treatments. Especially, the cells became enlarged, rounded and compact, and resembled embryonic cell mass in treated 3.0 mM. The 0.5 and 1.0 mM NaHS treatments efficiently promoted the growth, enhanced the enzyme activities such as SOD, POD, PAL, and 4CL (4-coumarate-Coenzyme A ligase), etc., as well as increased the levels of chlorophyll, carotenoid, AsA (Ascorbic acid), and total Fla or Lac in suspension cells. The best treatment was 1.0 mM treated for 4 or 7 days, and total Fla and Lac increased by 18.7% (4d) and 76.1% (7d) compared with the control, respectively. The high dose (3.0 mM) of NaHS treatment for 7 days restrained cells growth by decreasing photosynthetic pigments levels, and enhanced lipid peroxidation by increasing MDA content (141.5%) and the relative electrical conductivity levels (82.9%) compared to the control. High-dose NaHS also inhibited the above enzyme activities and total Flc and Lac accumulations. However, short-term 3.0 mM NaHS treatment (1d) could increase total Fla and Lac levels. This study provided new insights into the cell differentiation and the production of secondary metabolites in cell culture of G. biloba. Key message: Hydrogen sulfide promoted cell differentiation and embryonic cell mass formation, antioxidant ability, and flavonoids accumulation in Ginkgo biloba suspension cells. [ABSTRACT FROM AUTHOR]

The organic sulfur-containing compounds glucosinolates (GSLs) and the novel gasotransmitter H2S are known to have cardioprotective effects. This study investigated the antioxidant effects and H2S-releasing potential of three GSLs ((3E)-4-(methylsulfanyl)but-3-enyl GSL or glucoraphasatin, 4-hydroxybenzyl GSL or glucosinalbin, and (RS)-6-(methylsulfinyl)hexyl GSL or glucohesperin) in rat cardiac cells. It was found that all three GSLs had no effect on cardiac cell viability but were able to protect against H2O2-induced oxidative stress and cell death. NaHS, a H2S donor, also protected the cells from H2O2-stimulated oxidative stress and cell death. The GSLs alone or mixed with cysteine, N-acetylcysteine, glutathione, H2O2, iron and pyridoxal-5′-phosphate, or mouse liver lysates did not induce H2S release. The addition of GSLs also did not alter endogenous H2S levels in cardiac cells. H2O2 significantly induced cysteine oxidation in the cystathionine gamma-lyase (CSE) protein and inhibited the H2S production rate. In conclusion, this study found that the three tested GSLs protect cardiomyocytes from oxidative stress and cell death but independently of H2S signaling. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) belongs to the family of gasotransmitters and can modulate a myriad of biological signaling pathways. Among others, its cardioprotective effects, through antioxidant, anti-inflammatory, anti-fibrotic, and proangiogenic activities, are well-documented in experimental studies. Cardiorespiratory failure, predominantly cardiomyopathy, is a life-threatening complication that is the number one cause of death in patients with Duchenne muscular dystrophy (DMD). Although recent data suggest the role of H2S in ameliorating muscle wasting in murine and Caenorhabditis elegans models of DMD, possible cardioprotective effects have not yet been addressed. In this review, we summarize the current understanding of the role of H2S in animal models of cardiac dysfunctions and cardiac cells. We highlight that DMD may be amenable to H2S supplementation, and we suggest H2S as a possible factor regulating DMD-associated cardiomyopathy. [ABSTRACT FROM AUTHOR]

H2S, a gasotransmitter that can be produced both via the transsulfuration pathway and non-enzymatically, plays a key role in vasodilation and angiogenesis during pregnancy. In fact, the involvement of H2S production on plasma levels of sFLT1, PGF, and other molecules related to preeclampsia has been demonstrated. Interestingly, we have found that maternal fructose intake (a common component of the Western diet) affects tissular H2S production. However, its consumption is allowed during pregnancy. Thus, (1) to study whether maternal fructose intake affects placental production of H2S in the offspring, when pregnant; and (2) to study if fructose consumption during pregnancy can increase the risk of preeclampsia, pregnant rats from fructose-fed mothers (10% w/v) subjected (FF) or not (FC) to a fructose supplementation were studied and compared to pregnant control rats (CC). Placental gene expression, H2S production, plasma sFLT1, and PGF were determined. Descendants of fructose-fed mothers (FC) presented an increase in H2S production. However, if they consumed fructose during their own gestation (FF), this effect was reversed so that the increase disappeared. Curiously, placental synthesis of H2S was mainly non-enzymatic. Related to this, placental expression of Cys dioxygenase, an enzyme involved in Cys catabolism (a molecule required for non-enzymatic H2S synthesis), was significantly decreased in FC rats. Related to preeclampsia, gene expression of sFLT1 (a molecule with antiangiogenic properties) was augmented in both FF and FC dams, although these differences were not reflected in their plasma levels. Furthermore, placental expression of PGF (a molecule with angiogenic properties) was decreased in both FC and FF dams, becoming significantly diminished in plasma of FC versus control dams. Both fructose consumption and maternal fructose intake induce changes in molecules that contribute to increasing the risk of preeclampsia, and these effects are not always mediated by changes in H2S production. [ABSTRACT FROM AUTHOR]

• Different groundwater tables were set to analyze the fate of persulfate in soil. • Sulfate is not the final fate of sulfur in soil remediation by persulfate. • H 2 S accounts for 93.4-99.4 % of gaseous sulfur with maximum concentration of 33.0 ppm. • H 2 S concentration expected to decrease to a safe concentration after 20-85 days. Persulfate is considered a convenient and efficient remediation agent for organic contaminated soil. However, the potential risk of sulfur into the soil remediation by persulfate remains ignored. In this study, glass bottles with different persulfate dosages and groundwater tables were set up to simulate persulfate remediation of organic pollutants (aniline). The results found sulfate to be the main end-product (83.0%‒99.5%) of persulfate remediation after 10 days. Moreover, H 2 S accounted for 93.4%‒99.4% of sulfur reduction end-products, suggesting that H 2 S was the final fate of sulfur. H 2 S was released rapidly after one to three days at a maximum concentration of 33.0 ppm, which is sufficient to make a person uncomfortable. According to the fitted curve results, H 2 S concentration decreased to a safe concentration (0.15 ppm) after 20‒85 days. Meanwhile, the maximum concentration of methanethiol reached 0.6 ppm. These results indicated that secondary pollution from persulfate remediation could release harmful gases over a long time. Therefore, persulfate should be used more carefully as a remediation agent for soil contamination. [Display omitted] [ABSTRACT FROM AUTHOR]

Aim: Senescence of alveolar type II (AT2) cells is an important driver of pulmonary fibrosis. This study aimed to investigate whether and how dysregulation of hydrogen sulfide (H2S) production affected AT2 cell senescence, and then explored the effect of H2S on the communication between AT2 and fibroblasts. Methods: ICR mice were intratracheally administered with bleomycin (3 mg/kg). Sodium hydrosulfide (NaHS, 28 μmol/kg/d) was intraperitoneally injected for 2 weeks. The H2S‐generating enzyme cystathionine‐β‐synthase (CBS) knockout heterozygous (CBS+/−) mice were used as a low H2S production model. Results: Analysis of microarray datasets revealed downregulation of H2S‐generating enzymes in lung tissues of patients with pulmonary fibrosis. Decreased H2S production was correlated with higher levels of cell senescence markers p53 and p21 in bleomycin‐induced lung fibrosis. CBS+/− mice exhibited increased levels of p53 and p21. The numbers of AT2 cells positive for p53 and p21 were increased in CBS+/− mice as compared to control mice. H2S donor NaHS attenuated bleomycin‐induced AT2 cell senescence both in vivo and in vitro. H2S donor suppressed bleomycin‐induced senescence‐associated secretory phenotype (SASP) of AT2 cells via inhibiting p53/p21 pathway, consequently suppressing proliferation and myofibroblast transdifferentiation of fibroblasts. Mechanically, H2S suppressed p53 expression by enhancing the mouse double‐minute 2 homologue (MDM2)‐mediated ubiquitination and degradation of p53. Conclusion: H2S inactivated p53‐p21 pathway, consequently suppressing AT2 cell senescence as well as cell communication between senescent AT2 cells and fibroblasts. Aberrant H2S synthesis may contribute to the development of pulmonary fibrosis through promoting the activation loop involving senescent AT2 cells and activated fibroblasts. [ABSTRACT FROM AUTHOR]

Atomic hydrogen can be the result of different processes like electroplating, chemical and electrochemical pickling treatments, in welding or by cathodic processes in corrosive fluids. Moreover, adsorption of atomic hydrogen can affect materials in contact with high pressure gaseous hydrogen. Once entered the material, atomic hydrogen interacts with the metal structure and may produce a "damage" of various forms, such as Hydrogen Induced Cracking (HIC), delayed fracture, blistering and hydrogen embrittlement. In particular, when H2S is present ("sour service"), metallic materials, such as carbon and low alloy steels, may suffer hydrogen damage and hydrogen embrittlement. Sour service materials must be used in compliance with international accepted standards, used worldwide in oil and gas activities, when fluids are classified as sour. The present study has been carried out in order to set up an electrochemical method to charge with hydrogen two typical pipeline materials, carbon and low alloy steels. The reason of the use of an electrochemical method is to avoid any critical conditions from the point of view of preparation, safety and disposal. Hydrogen content in the specimens was measured by two different methods: hot glycerol bath and Inert Gas Fusion (IGF) analysis. Hydrogen content in the specimens is about 0.6–2 ppm; mechanical performances were assessed by means of J integral tests: a pronounced decrease of fracture toughness was observed for H charged specimens. [ABSTRACT FROM AUTHOR]

In order to address the issue of safe and efficient extraction of coalbed methane in H2S-containing coal mines, this study explored the impact of H2S on CH4 diffusion and displacement within coal. The molecular structure model of Guizhou Linhua (LH) coal was obtained based on the structural physical characterization experiment of coal such as 13C NMR, FTIR, XPS, we investigated the diffusion coefficient of CH4 in coal under different fixed adsorption amounts of H2S and examined the corresponding adsorption curves of mixed gas (H2S, CH4, CO2) under varying component proportions using the molecular simulation software Materials Studio. The results indicate that when H2S is present in the adsorption system, lower levels of absorbed H2S content by coal correspond to higher CH4 diffusion coefficients and improved diffusion effects. In other words, the presence of H2S inhibits CH4 diffusion within coal. Under identical temperature and pressure conditions, the adsorption capacity of coal for CH4, H2S, and CO2 follows this order: H2S > CO2 > CH4. When the mixture n(CO2)/n(CH4) is in the range of 0–150 % and there is H2S influence in the system, there is a significant reduction in CH4 adsorption capacity compared to two-component coals containing CO2/CH4, it becomes evident that H2S has an inhibitory effect on CO2 displacing CH4 within coal.

As an important gas signaling molecule, hydrogen sulfide (H2S) affects multiple organ systems, including the nervous, cardiovascular, digestive, and genitourinary, reproductive systems. In particular, H2S not only regulates female reproductive function but also holds great promise in the treatment of male reproductive diseases and disorders, such as erectile dysfunction, prostate cancer, varicocele, and infertility. In this review, we summarize the relationship between H2S and male reproductive organs, including the penis, testis, prostate, vas deferens, and epididymis. As lower urinary tract symptoms have a significant impact on penile erection disorders, we also address the potential ameliorative effects of H2S in erectile dysfunction resulting from bladder disease. Additionally, we discuss the regulatory role of H2S in cavernous smooth muscle relaxation, which involves the NO/cGMP pathway, the RhoA/Rho-kinase pathway, and K+ channel activation. Recently, various compounds that can alleviate erectile dysfunction have been reported to be at least partly dependent on H2S. Therefore, understanding the role of H2S in the male reproductive system may help develop novel strategies for the clinical treatment of male reproductive system diseases.

Abstract Oxidative stress induced by excess reactive oxygen species (ROS) is a primary pathogenic cause of acute kidney injury (AKI). Development of an effective antioxidation system to mitigate oxidative stress for alleviating AKI remains to be investigated. This study presents the synthesis of an ultra‐small Platinum (Pt) sulfur cluster (Pt5.65S), which functions as a pH‐activatable prefabricated nanozyme (pre‐nanozyme). This pre‐nanozyme releases hydrogen sulfide (H2S) and transforms into a nanozyme (Ptzyme) that mimics various antioxidant enzymes, including superoxide dismutase and catalase, within the inflammatory microenvironment. Notably, the Pt5.65S pre‐nanozyme exhibits an endo‐exogenous synergy‐enhanced antioxidant therapeutic mechanism. The Ptzyme reduces oxidative damage and inflammation, while the released H2S gas promotes proneurogenesis by activating Nrf2 and upregulating the expression of antioxidant molecules and enzymes. Consequently, the Pt5.65S pre‐nanozyme shows cytoprotective effects against ROS/reactive nitrogen species (RNS)‐mediated damage at remarkably low doses, significantly improving treatment efficacy in mouse models of kidney ischemia‐reperfusion injury and cisplatin‐induced AKI. Based on these findings, the H2S‐generating pre‐nanozyme may represent a promising therapeutic strategy for mitigating inflammatory diseases such as AKI and others.

Dysfunction of the vascular angiocrine system is critically involved in regenerative defects and fibrosis of injured organs. Previous studies have identified various angiocrine factors and found that risk factors such as aging and metabolic disorders can disturb the vascular angiocrine system in fibrotic organs. One existing key gap is what sense the fibrotic risk to modulate the vascular angiocrine system in organ fibrosis. Here, using human and mouse data, we discovered that the metabolic pathway hydrogen sulfide (H2S)-AMP-activated protein kinase (AMPK) is a sensor of fibrotic stress and serves as a key mechanism upregulating the angiocrine factor plasminogen activator inhibitor-1 (PAI-1) in endothelial cells to participate in lung fibrosis. Activation of the metabolic sensor AMPK was inhibited in endothelial cells of fibrotic lungs, and AMPK inactivation was correlated with enriched fibrotic signature and reduced lung functions in humans. The inactivation of endothelial AMPK accelerated lung fibrosis in mice, while the activation of endothelial AMPK with metformin alleviated lung fibrosis. In fibrotic lungs, endothelial AMPK inactivation led to YAP activation and overexpression of the angiocrine factor PAI-1, which was positively correlated with the fibrotic signature in human fibrotic lungs and inhibition of PAI-1 with Tiplaxtinin mitigated lung fibrosis. Further study identified that the deficiency of the antioxidative gas metabolite H2S accounted for the inactivation of AMPK and activation of YAP-PAI-1 signaling in endothelial cells of fibrotic lungs. H2S deficiency was involved in human lung fibrosis and H2S supplement reversed mouse lung fibrosis in an endothelial AMPK-dependent manner. These findings provide new insight into the mechanism underlying the deregulation of the vascular angiocrine system in fibrotic organs.

With the development of global oil and gas industry expands， pipeline steel corrosion in CO2 and H2S environments has become a significant impediment to oil and gas industry growth.The corrosion of pipeline steel is gradually receiving attention from scholars at home and abroad.In this paper， the corrosion behavior and mechanisms of pipeline steels under individual CO2， H2S， and combined CO2-H2S systems were summarized.It was highlighted that the partial pressures ratio of CO2 and H2S influences the extent of pipeline steel corrosion， with recent findings indicating that the critical value of CO2 and H2S partial pressures ratio was temperature-dependent.For the complex environment where CO2 and H2S coexist， this paper mainly introduced the protection technology of corrosion inhibitors and the optimization of corrosion resistant pipes to slow down the corrosion of pipeline steel.Furthermore，the future development direction in CO2 and H2S coexistence systems as well as more economical and effective anti-corrosion measures was prospected.

The kidney is an essential excretory organ that works as a filter of toxins and metabolic by-products of the human body and maintains osmotic pressure throughout life. The kidney undergoes several physiological, morphological, and structural changes with age. As life expectancy in humans increases, cell senescence in renal aging is a growing challenge. Identifying age-related kidney disorders and their cause is one of the contemporary public health challenges. While the structural abnormalities to the extracellular matrix (ECM) occur, in part, due to changes in MMPs, EMMPRIN, and Meprin-A, a variety of epigenetic modifiers, such as DNA methylation, histone alterations, changes in small non-coding RNA, and microRNA (miRNA) expressions are proven to play pivotal roles in renal pathology. An aged kidney is vulnerable to acute injury due to ischemia-reperfusion, toxic medications, altered matrix proteins, systemic hemodynamics, etc., non-coding RNA and miRNAs play an important role in renal homeostasis, and alterations of their expressions can be considered as a good marker for AKI. Other epigenetic changes, such as histone modifications and DNA methylation, are also evident in AKI pathophysiology. The endogenous production of gaseous molecule hydrogen sulfide (H2S) was documented in the early 1980s, but its ameliorative effects, especially on kidney injury, still need further research to understand its molecular mode of action in detail. H2S donors heal fibrotic kidney tissues, attenuate oxidative stress, apoptosis, inflammation, and GFR, and also modulate the renin–angiotensin–aldosterone system (RAAS). In this review, we discuss the complex pathophysiological interplay in AKI and its available treatments along with future perspectives. The basic role of H2S in the kidney has been summarized, and recent references and knowledge gaps are also addressed. Finally, the healing effects of H2S in AKI are described with special emphasis on epigenetic regulation and matrix remodeling.

In this study, the corrosion behavior of N80 steel exposed to 80 bar supercritical CO2 and 0–15 bar H2S environments was investigated by weight loss test, surface analysis, water chemistry simulation, corrosion thermodynamic and kinetic calculations. The results show that a very low H2S pressure of 0.004 bar in supercritical CO2 environment boosts the corrosion rate of N80 steel, whereas the rate is considerably reduced with further increasing the H2S pressure. The variation of corrosion rate with H2S pressure largely depends on the changes in cathode process and overall protectiveness of corrosion product film caused by H2S. As the H2S pressure rises, the evolution of corrosion product film on the steel is as follows: FeCO3 dominated film below 0.16 bar H2S, FeCO3 and FeS mixed film within 0.16–4 bar H2S, and FeS dominated film over 4 bar H2S. Benefiting from the integrity of film structure and the uniformity of film composition, N80 steel experiences uniform corrosion in the formation environment of FeCO3 or FeS dominated film. However, the localized corrosion easily occurs in the formation environment of FeCO3 and FeS mixed film owing to the loss of film integrity induced by uneven precipitation of FeCO3 inside the corrosion product film.

The risk of corrosion failure of submarine pipeline increases sharply，and it is necessary to study the corrosion behavior and corrosion rate of submarine pipeline.In this work，18 groups of six factors and three-level orthogonal experiments were carried out for the submarine pipelines commonly used steel X65 steel in high temperature and high pressure reactors.The synergistic corrosion behavior of X65 steel by CO2，H2S，pH value，Cl-，temperatures and flow rates was studied，and the main controlling factors for corrosion were determined as CO2partial pressure ＞H2S partial pressure ＞Cl-concentration ＞pH value ＞flow rate ＞temperature.From the results of scanning electron microscope，the synergistic corrosion behavior of H2S，CO2and Cl-was clarified: CO2formed dense FeCO3，which was located at the bottom of the corrosion product film，and the surface was Fe sulfide.Moreover，Cl-passed through the corrosion product film to promote the occurrence of corrosion.Finally，based on the orthogonal experimental data，a six-factor corrosion rate prediction model was established，and the prediction model error was less than 20%.

The effect of La3+ on the hydrogen permeation behavior of 27CrMo44S/1 steel in acidic environments containing H2S is investigated through the measurement of steady-state permeation current density (i∞), hydrogen diffusivity (D), and subsurface hydrogen concentration (C0). Results indicate that the addition of La3+ can remarkably reduce i∞. The corrosion products with La3+ involved in the film formation process in the H2S-free environment have a good hydrogen barrier effect, but the addition of La3+ hardly influence the D value of 27CrMo44S/1 steel in the H2S-containing environment. However, the presence of La3+ substantially reduces the C0 on metal surface regardless of the presence of H2S in the solution. Static immersion and tensile experiments illustrate that the addition of La3+ can improve the corrosion resistence and plasticity loss of the material in the H2S environment.

Background. Hydrogen sulfide (H2S) in high concentrations is a toxic pollutant. Due to the risk of its impact on the organism of people living in the areas of its production as part of natural gas, it is necessary to expand the pathogenetically substantiated profile of diagnosing the consequences of its impact. The purpose of the study is to evaluate the effect of hydrogen sulfide (its sulfide ions H–HS) on the processes of senescence and peroxidation in the kidneys of old rats. Materials and methods: With the help of an H2S (Na2S) donor, intraperitoneal toxic effects of sulfide ions were simulated in 18-20-months-old rats. Sections and homogenates of renal tissue were examined for the presence of lipofuscincontaining senescent cells (SC), the level of interleukin-6, catalase, and oxidative modification of proteins in the presence of metals of variable valence. Results. SCs located diffusely between the renal bodies of the juxtamedullary and subcapsular nephrons of the kidney were identified. An increase in the level of interleukin-6, catalase and aldehyde dinitrophenylhydrazones was recorded. Conclusions. The applied experimental approach using Na2S as a donor promotes the formation of a senescent morphotype in a functioning kidney in old rats. The functional features of the kidneys determine the predominant toxic load on the renal corpuscles of the nephrons. Accumulation of lipofuscin by cells and an increase in the level of pro-inflammatory interleukin-6 are promoted by active processes of prooxidation of the protein components of cells. Distribution of the secretion of SA contributes to increased metabolic inconsistency and forms a vicious circle that increases the activity of the antioxidant catalase.

ABSTRACT Methanethiol (MT) is a sulfur-containing compound produced during dimethylsulfoniopropionate (DMSP) degradation by marine bacteria. The C–S bond of MT can be cleaved by methanethiol oxidases (MTOs) to release a sulfur atom. However, the cleaving process remains unclear, and the species of sulfur product is uncertain. It has long been assumed that MTOs produce hydrogen sulfide (H2S) from MT. Herein, we studied the MTOs in the Rhodobacteraceae family—whose members are important DMSP degraders ubiquitous in marine environments. We identified 57 MTOs from 1,904 Rhodobacteraceae genomes. These MTOs were grouped into two major clusters. Cluster 1 members share three conserved cysteine residues, while cluster 2 members contain one conserved cysteine residue. We examined the products of three representative MTOs both in vitro and in vivo. All of them produced sulfane sulfur other than H2S from MT. Their conserved cysteines are substrate-binding sites in which the MTO–S–S–CH3 complex is formed. This finding clarified the sulfur product of MTOs and enlightened the MTO-catalyzing process. Moreover, this study connected DMSP degradation with sulfane sulfur metabolism, filling a critical gap in the DMSP degradation pathway and representing new knowledge in the marine sulfur cycle field.IMPORTANCEThis study overthrows a long-time assumption that methanethiol oxidases (MTOs) cleave the C–S bond of methanethiol to produce both H2S and H2O2—the former is a strong reductant and the latter is a strong oxidant. From a chemistry viewpoint, this reaction is difficult to happen. Investigations on three representative MTOs indicated that sulfane sulfur (S0) was the direct product, and no H2O2 was produced. Finally, the products of MTOs were corrected to be S0 and H2O. This finding connected dimethylsulfoniopropionate (DMSP) degradation with sulfane sulfur metabolism, filling a critical gap in the DMSP degradation pathway and representing new knowledge in the marine sulfur cycle field.

Immunoregulation is one of the important factors in wound healing. Currently, wound dressings with immunoregulation is necessary to overcome the complicated interventions, high-cost treatments and uncontrolled release behaviors. In this study, a novel Cu and Zn loaded nanofiber dressing (FM-Cu-Zn) with immunoregulation and controllable release without external intervention was prepared by electrospinning. The dressing is composed of ZnCl2, CuS nano particles, poly-3-hydroxybutyrate-co-4-hydroxybutyrate (P34HB). Where Zn2+ is the “promoter” of immunotherapeutic activity by reducing the environmental pH to trigger H2S and Cu2+ releasing from CuS. Then, H2S and Cu2+ can regulate the inflammatory response and accelerate wound healing. The results in vivo indicated the FM-Cu-Zn nanofiber dressing showed better anti-inflammatory and wound healing ability, the wound healing rate was upto 95 % after 11 days treatment by the obtianed dressing, which was much higher compared to control groups. Notably, the dressing can promote macrophage polarization toward a pro-regenerative M2 phenotype without any external intervention. Therefore, the FM-Cu-Zn nanofiber with the immunomodulatory property can serve as a promising dressing in wound healing field.

The construction of fast response, low detection limit and high stability gas sensors by means of bionics is of great significance, for the sake of fabricating more efficient and compatible materials and exploring their functional principles. The high olfactory sensitivity of dogs and mice in nature is closely related to the wrinkled structure of their turbinates, which provides inspiration for us to design the structure of gas-sensing sensing materials. In our study, various scales and concentrations Au nanoparticles were deposited on spindle-shaped wrinkled ZnO nanoparticles via a facile hydrothermal method and subsequent a series of reduction process, resulting in different sensing performances toward H 2 S: when the loading amount of small-sized gold nanoparticles was 0.5 wt% (0.5 wt% Au/ZnO), sample showed the highest response value of 39.23 at the optimal working temperature of 215 °C, which was 6.4 times that of pure wrinkled ZnO. The superior sensing performance can be attributed to the control of two mechanisms: adsorption-desorption mechanism and sulfurization-desulfurization mechanism. Moreover, 0.5 wt% Au/ZnO constructed in a sample and low-cost way provides a strategy to design bio-inspired materials for evaluate trace concentrations of H 2 S. [ABSTRACT FROM AUTHOR]

The existence level and metabolic mechanism of hydrogen sulfide (H 2 S) have been proved to have an important impact on organisms, even affecting the generation and development of many neurological diseases. Therefore, it is essential to develop sensitive and accurate H 2 S sensors to detect H 2 S concentration at trace level and provide effective research tools for studying the mechanism of action of H 2 S on organisms. MXene is a class of two-dimensional transition metal carbonitrides with a graphene-like structure, which indicating great application prospects as a biosensor due to its large specific surface area and good conductivity. In this work, the properties of multilayer Ti 3 C 2 T x MXene materials are optimized concerning their physical structure and functional groups. Based on the Li + intercalation method, SL-Ti 3 C 2 T x MXene is prepared by a mild route, and its electrochemical performance is optimized by high temperature calcination under high purity argon conditions. The change in material properties at high temperature is discussed through structural and chemical analysis, and the optimal calcination temperature is determined to be 700 °C. The constructed H 2 S electrochemical sensor exhibits high stability and reproducibility in applications, with a detection range of 0.1–500 μM, and the detection limit is reduced to 5.77 nM. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) and sulfur dioxide (SO2), recognized as endogenous sulfur-containing gas signaling molecules, were the third and fourth molecules to be identified subsequent to nitric oxide and carbon monoxide (CO), and exerted diverse biological effects on the cardiovascular system. However, the exact mechanisms underlying the actions of H2S and SO2 have remained elusive until now. Recently, novel post-translational modifications known as S-sulfhydration and S-sulfenylation, induced by H2S and SO2 respectively, have been proposed. These modifications involve the chemical alteration of specific cysteine residues in target proteins through S-sulfhydration and S-sulfenylation, respectively. H2S induced S-sulfhydrylation can have a significant impact on various cellular processes such as cell survival, apoptosis, cell proliferation, metabolism, mitochondrial function, endoplasmic reticulum stress, vasodilation, anti-inflammatory response and oxidative stress in the cardiovascular system. Alternatively, S-sulfenylation caused by SO2 serves primarily to maintain vascular homeostasis. Additional research is warranted to explore the physiological function of proteins with specific cysteine sites, despite the considerable advancements in comprehending the role of H2S-induced S-sulfhydration and SO2-induced S-sulfenylation in the cardiovascular system. The primary objective of this review is to present a comprehensive examination of the function and potential mechanism of S-sulfhydration and S-sulfenylation in the cardiovascular system. Proteins that undergo S-sulfhydration and S-sulfenylation may serve as promising targets for therapeutic intervention and drug development in the cardiovascular system. This could potentially expedite the future development and utilization of drugs related to H2S and SO2. [ABSTRACT FROM AUTHOR]

A discharge-flow reactor combined with modulated molecular beam mass spectrometry technique was employed to determine the rate constants of H-atom reactions with hydrogen sulfide and thiirane. The rate constants for both reactions were determined at a total pressure of 2 Torr from 220 to 950 K under pseudo-first-order conditions by monitoring either consumption of H atoms in excess of H2S (C4H4S) or the molecular species in excess of atomic hydrogen. For H + H2S reaction, a suggested previously strong curvature of the Arrhenius plot was confirmed: kl = 8.7 × 10−13 × (T/298)2.87 × exp(−125/T) cm3 molecule−1 s−1 with a conservative uncertainty of 15% at all temperatures. Non-Arrhenius behavior was also observed for the reaction of H-atom with C2H4S, with the experimental rate constant data being best fitted to a sum of two exponential functions: k2 = 1.85 × 10−10 exp(−1410/T) + 4.17 × 10−12 exp(−242/T) cm3 molecule−1 s−1 with an independent of temperature uncertainty of 15%. [ABSTRACT FROM AUTHOR]

Abstract—Ischemia–reperfusion is a cascade of complex and interrelated pathological processes underlying many human diseases, including such socially significant diseases as stroke, myocardial infarction, acute renal failure, etc. The present review considers modern ideas about the main biochemical and signal-regulatory processes in the cell under conditions of ischemia–reperfusion. Both generally accepted and newly developed ways of ischemia–reperfusion lesion correction aimed at different chains of this pathological process are considered. [ABSTRACT FROM AUTHOR]

Abstract—Cancer cells are characterized by an increased level of metabolism and are highly dependent on the correct functioning of the processes that ensure homeostasis. Reactive sulfur species (RSS) are important molecular modulators of metabolic processes in both healthy and tumor cells. The effect of RSS and, in particular, H2S, on key cellular systems, including the ubiquitin–proteasome system (UPS), which provides the destruction of most intracellular proteins, has been shown. The main components of the UPS are proteasomes, multisubunit protein complexes, within which proteolysis occurs. At the same time, data on the effect of H2S directly on the pool of proteasomes in tumor cells are insufficient. Here, we studied the effect of incubation of SW620B8-mCherry colorectal adenocarcinoma cells expressing a fluorescently labeled proteasome subunit with 50, 100, and 200 µM of the hydrogen sulfide donor GYY4137. The effect of the substance on the proteasome pool was assessed 6, 24, 48, and 72 h after administration. It was shown that the chymotrypsin-like and caspase-like proteasome activity decreases in cells incubated with 200 µM of the GYY4137 for 24 h. This coincided with an increase in the expression of proteasome subunit genes. In lysates of cells incubated with 200 µM GYY4137 for 48 h an increase in the content of the constitutive β5 subunit was observed and the activity of proteasomes leveled off. Following prolonged incubation with GYY4137 (72h), an increase in the expression levels of some proteasome genes was also observed, although this did not have a significant effect on the activity and subunit composition of proteasomes. Thus, the obtained data indicate the modulation of proteasome activity by the hydrogen sulfide donor and the effect of GYY4137 on transcription and translation of proteasome genes. [ABSTRACT FROM AUTHOR]

We aimed to investigate the mechanism underlying the roles of miRNA-377, Cystathionine-β-synthase (CBS), and hydrogen sulfide (H2S) in the development of hypoxic-ischemic encephalopathy (HIE). We investigated the relationship between CBS, H2S, and miR-377 in both humans with HIE and animals with hypoxic-ischemic insult. An animal model of fetal rats with hypoxic-ischemic brain injury was established, and the fetal rats were randomly assigned to control and hypoxic-ischemic groups for 15 min (mild) and 30 min (moderate) groups. Human samples were collected from children diagnosed with HIE. Healthy or non-neurological disease children were selected as the control group. Hematoxylin–eosin (HE) staining, quantitative real-time polymerase chain reaction (qRT-PCR), enzyme-linked immunosorbent assay (ELISA), and western blot were used to conduct this study. Hypoxia–ischemia induced pathological alterations in brain tissue changes were more severe in groups with severe hypoxic insult. miRNA-377 expression levels were upregulated in brain tissue and serum of fetal rats and human samples with HIE compared to controls. Conversely, CBS and H2S expression levels were significantly decreased in both human and animal samples compared to controls. Our findings suggest that CBS is a target gene of miR-377 which may contribute to the development of HIE by regulating CBS/H2S. H2S has a protective effect against hypoxic damage in brain tissue. The study provides new insights into the potential mechanisms underlying the protective role of H2S in hypoxic brain damage and may contribute to the development of novel therapies for HIE. [ABSTRACT FROM AUTHOR]

A hybrid desulfurization process combining a physical filtration stage on cellular concrete (CC abiotic filter, called CCAF) and a biotrickling filter (called BTF) filled with expanded schist as packing material was used to remove high H2S concentrations from a synthetic gas containing dinitrogen (N2), dioxygen (O2) and H2S without the addition of a nutritive solution. Provided that small amounts of oxygen are present in the gas (1.2 ± 0.1% in volume), the global removal efficiency was 100%, and the global removal capacity reached 35 ± 2 gH2S m−3 h−1 for a total empty bed residence time (EBRT) of 120 s (CCAF + BTF). The resilience of the desulfurization process was demonstrated by applying severe changes in the H2S concentrations, from 160 to 1150 ± 20 mg m−3 for an EBRT = 120 s. According to the performances of the abiotic filter, which can decline over time due to the lifetime of the cellular concrete (137 days), the biotrickling filter reacted either as a refining system or as an efficient system able to treat significant H2S loading rates (up to 45 ± 3 gH2S m−3 h−1). Depending on the operating conditions, the increase in the pressure drops of the biotrickling filter (from 45 ± 3 to 234 ± 8 Pa m−1) highlighted biomass accumulation, especially extremophilic Acidithiobacillus sp. Considering the cellular concrete abiotic filter alone, removal capacities of up to 56 ± 3 gH2S m−3 h−1 were recorded for an EBRT of 60 s, demonstrating that gases such as landfill biogas or household biogas could be efficiently treated using this simple technique. [ABSTRACT FROM AUTHOR]

Modulation of mitochondrial K channels represents a pharmacological strategy to promote cardioprotective effects. Isothiocyanates emerge as molecules capable of releasing hydrogen sulfide (H2S), an endogenous pleiotropic gasotransmitter responsible for anti-ischemic cardioprotective effects also through the involvement of mitoK channels. Erucin (ERU) is a natural isothiocyanate resulting from the enzymatic hydrolysis of glucosinolates (GSLs) present in Eruca sativa Mill. seeds, an edible plant of the Brassicaceae family. In this experimental work, the specific involvement of mitoKATP channels in the cardioprotective effect induced by ERU was evaluated in detail. An in vivo preclinical model of acute myocardial infarction was reproduced in rats to evaluate the cardioprotective effect of ERU. Diazoxide was used as a reference compound for the modulation of potassium fluxes and 5-hydroxydecanoic acid (5HD) as a selective blocker of KATP channels. Specific investigations on isolated cardiac mitochondria were carried out to evaluate the involvement of mitoKATP channels. The results obtained showed ERU cardioprotective effects against ischemia/reperfusion (I/R) damage through the involvement of mitoKATP channels and the consequent depolarizing effect, which in turn reduced calcium entry and preserved mitochondrial integrity. [ABSTRACT FROM AUTHOR]

To prevent corrosion or abrasion damage of equipment used in hydrogen sulfide (H2S) and sand conditions, high wear and corrosion-resistant coatings are needed. In this study, a cemented carbide Cr3C2–25NiCr coating was applied to 304 stainless steel substrate via high-velocity oxygen fuel thermal spraying to investigate its wear and corrosion resistance in an oil and gas field model environment. The coating exhibits high hardness (1062.4HV0.1) that is five times greater than the substrate and a 50% reduction in wear pit depth. The corrosion rate of the coating is 72% less than that of stainless steel (0.17 mm/y). These results suggest that Cr3C2–25NiCr coating has great potential for use in the oil and gas industry. [ABSTRACT FROM AUTHOR]

Sulfur metabolism is an important life metabolism in microbes. Sulfur transportation, assimilation, metabolic regulation and biosynthesis of important sulfur-containing compounds by microorganisms not only affect the growth and metabolism of microorganisms, but also influence the stress resistance and robustness of microorganisms in inhibitory environments. Most of current researches are focusing on the microbial sulfate assimilatory reduction process and H2S production with few studies on microbial sulfur metabolism and stress resistance. This review summarized sulfate transport, assimilatory reduction pathway, and regulatory networks in the process of sulfur metabolism. Combined with the oxidative stress responses of microorganisms under different stress conditions, the review discussed mechanism by which sulfur-containing compounds such as hydrogen sulfide, glutathione and cysteine improve the stress resistance of microorganisms. The revelation of molecular mechanism between sulfur metabolism and microbial stress resistance will not only help understand microbial sulfur metabolism further, but also provide candidate molecular targets for the design and construction of efficient and robust industrial strains. [ABSTRACT FROM AUTHOR]

Biomass exploitation is a global trend due to the circular economy and the environmentally friendly spirit. Numerous applications are now based on the use of biomass-derived products. Hydrogen sulfide (H2S) is a highly toxic and environmentally hazardous gas which is emitted from various processes. Thus, the efficient removal of this toxic hazardous gas following cost-effective processes is an essential requirement. In this study, we present the synthesis and characterization of biomass-derived activated carbon/zinc oxide (ZnO@AC) composites from different biomass sources as potential candidates for H2S sorption. The synthesis involved a facile method for activated carbon production via pyrolysis and chemical activation of biomass precursors (spent coffee, Aloe-Vera waste leaves, and corncob). Activated carbon production was followed by the incorporation of zinc oxide nanoparticles into the porous carbon matrix using a simple melt impregnation method. The synthesized ZnO@AC composites were characterized using X-ray diffraction (XRD), infrared spectroscopy (IR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and nitrogen porosimetry. The H2S removal performance of the ZnO@AC composites was evaluated through sorption experiments using a handmade apparatus. Our findings demonstrate that the Aloe-Vera-, spent coffee-, and corncob-derived composites exhibit superior H2S sorption capacity up to 106 mgH2S/gads., 66 mgH2S/gads., and 47 mgH2S/gads., respectively. [ABSTRACT FROM AUTHOR]

Significance: Reactive sulfur species (RSS) have been recently recognized as redox molecules no less important than reactive oxygen species or reactive nitrogen species. They possess regulatory and protective properties and are involved in various metabolic processes, thereby contributing to the maintenance of human health. It has been documented that many disorders, including neurological, cardiovascular, and respiratory diseases, diabetes mellitus (DM), and cancer, are related to the disruption of RSS homeostasis. Recent Advances: There is still a growing interest in the role of RSS in human diseases. Since a decrease in hydrogen sulfide or other RSS has been reported in many disorders, safe and efficient RSS donors have been developed and tested under in vitro conditions or on animal models. Critical Issues: Cardiovascular diseases and DM are currently the most common chronic diseases worldwide due to stressful and unhealthy lifestyles. In addition, because of high prevalence and aging of the population, neurological disorders including Parkinson's disease and Alzheimer's disease as well as respiratory diseases are a formidable challenge for health care systems. From this point of view, the knowledge of the role of RSS in these disorders and RSS modulation options are important and could be useful in therapeutic strategies. Future Directions: Improvement and standardization of analytical methods used for RSS estimation are crucial for the use of RSS as diagnostic biomarkers. Finding good, safe RSS donors applicable for therapeutic purposes could be useful as primary or adjunctive therapy in many common diseases. Antioxid. Redox Signal. 39, 1000–1023. [ABSTRACT FROM AUTHOR]

Significance: Hydrogen sulfide (H2S) is considered to be a gasotransmitter along with carbon monoxide (CO) and nitric oxide (NO), and is known as a key regulator of physiological and pathological activities. S-sulfhydration (also known as persulfidation), a mechanism involving the formation of protein persulfides by modification of cysteine residues, is proposed here to explain the multiple biological functions of H2S. Investigating the properties of protein persulfides can provide a foundation for further understanding of the potential functions of H2S. Recent Advances: Multiple methods have been developed to determine the level of protein persulfides. It has been demonstrated that protein persulfidation is involved in many biological processes through various mechanisms including the regulation of ion channels, enzymes, and transcription factors, as well as influencing protein–protein interactions. Critical Issues: Some technical and theoretical questions remain to be solved. These include how to improve the specificity of the detection methods for protein persulfidation, why persulfidation typically occurs on one or a few thiols within a protein, how this modification alters protein functions, and whether protein persulfidation has organ-specific patterns. Future Directions: Optimizing the detection methods and elucidating the properties and molecular functions of protein persulfidation would be beneficial for current therapeutics. In this review, we introduce the detailed mechanism of the persulfidation process and discuss persulfidation detection methods. In addition, this review summarizes recent discoveries of the selectivity of protein persulfidation and the regulation of protein functions and cell signaling pathways by persulfidation. Antioxid. Redox Signal. 39, 829–852. [ABSTRACT FROM AUTHOR]

Background: Ethylmalonic encephalopathy (EE) is a rare intoxication-type metabolic disorder with multisystem involvement. It is caused by mutations in ETHE1, which encodes the ETHE1 enzyme in the mitochondrial matrix that plays a key role in hydrogen sulfide (H2S) detoxification acting as a sulphur dioxygenase. Results: This review focuses on the clinical, metabolic, genetic and neuroradiological features of 70 reported cases, including two new cases. The common manifestations of EE are psychomotor regression, hypotonia, developmental delay, petechia, pyramidal signs, chronic diarrhoea, orthostatic acrocyanosis and failure to thrive, respectively. A significant difference was found in EMA and C4 levels (p=0.003, p=0.0236) between classical and mild phenotypes. Urinary EMA, C4 and C5 levels were found to exhibit normal values in milder cases during attack-free periods. The most common ETHE1 gene homozygous state mutations were (p.R163Q) (c.488G>A), exon 4 deletion, (p.R163W)(c.487C>T), (p.Glu44ValfsTer62)(c.131_132delAG) and (p.M1I)(c.3G>T) mutations, respectively. Fifty-two patients underwent cranial MRI. Basal ganglia signal alterations were detected in 42 cases. Of the 70 cases, eight had a mild phenotype and slow neurological progression with low levels of ethylmalonic acid (EMA) and C4 acylcarnitine. The current age of alive patients in the published articles with mild phenotype was significantly higher than the classical phenotype. (p=0.002). Reducing the accumulation and inducing detoxification of sulfide is the main long-term treatment strategy for EE, including metronidazole, N-acetylcysteine (NAC), dietary modification, liver transplantation and continuous renal replacement therapy (CRRT). Conclusion: Measuring EMA and C4 acylcarnitine during metabolic attacks is critical to diagnosing EE, allowing for early treatment initiation to prevent further encephalopathic crises. Experience with liver transplantation, diet and CRRT, is currently limited. An early multidisciplinary approach with combination therapies is vital to prevent irreversible neurological damage. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to evaluate the protection performance of zinc as sacrificial anode for ABS A steel in the presence of H2S under different temperatures, pH and salinities. Design/methodology/approach: In this paper, weight loss measurements and electrochemical measurements are used to evaluate the corrosion degree of zinc and ABS A steel. Findings: Under the conditions involved in this work, it is shown that zinc is a nice sacrificial anode with the reason of its stable potential and excellent anode current efficiency according to the relevant standard. And it is also found that the hydrogen evolution does not occur on ABS A steel specimens. The potential difference between cathode and anode is suitable; thus, it can be concluded that each steel is well protected. Originality/value: To the best of the authors' knowledge, no other study has analyzed the protection mechanism and effect of zinc as sacrificial anode in H2S-containing environments under high temperature at present. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) promotes microangiogenesis and revascularization after ischemia. Neovascularization starts with the destruction of intercellular junctions and is accompanied by various endothelial cell angiogenic behaviors. Follistatin-like 1 (FSTL1) is a cardiovascular-protective myokine that works against ischemic injury. The present study examined whether FSTL1 was involved in H2S-induced angiogenesis and explored the underlying molecular mechanism. We observed that H2S accelerated blood perfusion after ischemia in the mouse hindlimb ischemia model. Western blot analysis showed that H2S stabilized FSTL1 transcript and increased FSTL1 and Human antigen R (HuR) levels in skeletal muscle. RNA-interference HuR significantly inhibited the H2S-promoted increase in FSTL1 levels. Exogenous FSTL1 promoted the wound-healing migration of human umbilical vein endothelial cells (HUVECs) and increased monolayer endothelial barrier permeability. Immunostaining showed that FSTL1 increased interendothelial gap formation and decreased VE-Cadherin, Occludin, Connexin-43, and Claudin-5 expression. In addition, FSTL1 significantly increased the phosphorylation of Src and VEGFR2. However, the Src inhibitor, not the VEGFR2 inhibitor, could block FSTL1-induced effects in angiogenesis. In conclusion, we demonstrated that H2S could upregulate the expression of FSTL1 by increasing the HuR levels in skeletal muscle, and paracrine FSTL1 could initiate angiogenesis by opening intercellular junctions via the Src signaling pathway. [ABSTRACT FROM AUTHOR]

Reduced volatile sulfur compounds emitted from e.g. livestock production and biogas production facilities contribute to general air pollution and local odour nuisance. Improved technologies are required to mitigate the emissions of both hydrogen sulfide and organic sulfur compounds. The present study examines the oxidative absorption of reduced sulfur compounds, i.e. hydrogen sulfide, methanethiol and dimethyl sulfide in a wet oxidation process with cupric chloride. It was found that this process efficiently removes both hydrogen sulfide and methanethiol with removal efficiencies >94% under all process conditions tested, while the removal of dimethyl sulfide was in the range 20–40%. The main products determined were dimethyl disulfide, dimethyl trisulfide and elemental sulfur. It was shown that the process was more efficient than the similar process with ferric ions and higher removal could be obtained with lower residence times. Furthermore, though employing cupric ion as metal catalysts results in the production of gaseous sulfur compounds, it is estimated that this process is efficient for deodorization due to the higher odour threshold values of the product compounds and the pH range is optimal for gas streams containing CO2. [ABSTRACT FROM AUTHOR]

Compared to extensive studies on affecting parameters in sulfur removal with ZnO adsorbents from coal gasification syngas, similar studies conducted for biomass gasification syngas (BGS) are quite rare. Thus, considering the BGSs with high water content, this study was performed to investigate the effect of H2O presence in syngas on sulfur removal capacity (SRC) of ZnO adsorbents. Initially, the effect of gas composition and temperature on SRC in binary gas mixture was investigated. While H2O decreased the SRC, as expected, the highest reduction in the capacity occurred in the CO–H2S gas mixture due to observed COS formation. Second, the SRCs and resulting COS formation were compared for synthetic syngas mixtures having different water contents and for different amounts of adsorbents. Finally, the separate and combined effects of temperature and H2O on SRC and COS formation in synthetic syngas were investigated by comparing SRCs of typical syngas under wet and dry conditions. The results showed that increasing the amount of adsorbent and temperature results in higher SRC due to a reduction in COS formation through the reactions of COS with H2 and H2O. This indicates that it is critical to control the residence time of syngas and temperature to reduce COS formation during ZnO adsorption. [ABSTRACT FROM AUTHOR]

Summary: Glucose‐6‐phosphate dehydrogenases (G6PDs) are essential regulators of cellular redox. Hydrogen sulfide (H2S) is a small gasotransmitter that improves plant adaptation to stress; however, its role in regulating G6PD oligomerization to resist oxidative stress remains unknown in plants.Persulfidation of cytosolic G6PDs was analyzed by mass spectrometry (MS). The structural change model of AtG6PD6 homooligomer was built by chemical cross‐linking coupled with mass spectrometry (CXMS). We isolated AtG6PD6C159A and SlG6PDCC155A transgenic lines to confirm the in vivo function of persulfidated sites with the g6pd5,6 background.Persulfidation occurs at Arabidopsis G6PD6 Cystine (Cys)159 and tomato G6PDC Cys155, leading to alterations of spatial distance between lysine (K)491‐K475 from 42.0 Å to 10.3 Å within the G6PD tetramer. The structural alteration occurs in the structural NADP+ binding domain, which governs the stability of G6PD homooligomer. Persulfidation enhances G6PD oligomerization, thereby increasing substrate affinity. Under high salt stress, cytosolic G6PDs activity was inhibited due to oxidative modifications. Persulfidation protects these specific sites and prevents oxidative damage.In summary, H2S‐mediated persulfidation promotes cytosolic G6PD activity by altering homotetrameric structure. The cytosolic G6PD adaptive regulation with two kinds of protein modifications at the atomic and molecular levels is critical for the cellular stress response. [ABSTRACT FROM AUTHOR]

In order to alleviate the pollution caused by the odor gas generated by the degradation or decay of kitchen waste, eight strains with deodorizing effect on NH3 and H2S were isolated and screened from sludge and kitchen waste compost, and mixed them to prepare a composite microbial deodorant. The deodorization effect, physicochemical properties and microbial community changes during composting were studied. The results from response surface analysis showed that the degradation rate of NH4 + ‑N was 92.55% under optimal temperature, pH and inoculum for NH4 + ‑N degradation rate were 27℃, 6.21 and 14%, respectively. The maximum yield of SO4 2- was 173.57 mg/L when the optimal temperature, pH and inoculum for SO4 2- production were 29℃, 6.61 and 5%, respectively. The removal rates of H2S and NH3 reached 61.72% and 55.32%, respectively after adding microbial agents in kitchen waste composting. Meanwhile, it reduced the water content, C/N and pH. Besides, it promoted the composting temperature rising, and extended the time of high temperature. In addition, the addition of bacterial agent is beneficial to the change of microbial community structure, increases the number of bacteria that remove ammonia and hydrogen sulfide, accelerates the metabolic transformation process of hydrogen sulfide and ammonia, and suppresses the amount of ammonia and hydrogen sulfide released, which has promising application potential for the control of kitchen waste odor gases. [ABSTRACT FROM AUTHOR]

Traditional treatment methods for tumors are inefficient and have severe side effects. At present, new therapeutic methods such as phototherapy, chemodynamic therapy, and gasodynamic therapy have been innovatively developed. High concentrations of hydrogen sulfide (H2S) gas exhibit cancer-suppressive effects. Herein, a Prussian blue-loaded tetra-sulfide modified dendritic mesoporous organosilica (PB@DMOS) was rationally constructed with glutathione (GSH)-triggered/photothermal-enhanced H2S signaling molecule release properties for gas therapy. The as-synthesized nanoplatform confined PB nanoparticles in the mesoporous structure of organosilica silica due to electrostatic adsorption. In the case of a GSH overexpressed tumor microenvironment, H2S gas was controllably released. And the temperature increases due to the photothermal effects of PB nanoparticles, further enhancing H2S release. At the same time, PB nanoparticles with excellent hydrogen peroxide catalytic performance also amplified the efficiency of tumor therapy. Thus, a collective nanoplatform with gas therapy/photothermal therapy/catalytic therapy functionalities shows potential promise in terms of efficient tumor therapy. [ABSTRACT FROM AUTHOR]

A ratiometric dual-mode probe NI-SH based on 1,8-Naphthalimide was prepared for H2S detection. When treated with H2S, the fluorescence of NI-SH changes from blue (456 nm) to green (540 nm), and displays significant color variation (colorless to yellow) that can visible to the naked eye. Further investigation shows that the NI-SH has high sensitivity, selectivity, and low detection limit at about 0.2 μM, and with large Stokes shift (84 nm). The intermolecular charge transfer (ICT) response mechanism of NI-SH was further studied by analyzing the distributions of the molecular orbital. Besides, NI-SH exhibits a ratiometric fluorescence response in living Hela cells. [ABSTRACT FROM AUTHOR]

A two-dimensional (2D) van der Waals material composed only of tellurium (Te) atoms—tellurene—is drawing attention because of its high intrinsic electrical conductivity and strong interaction with gas molecules, which could allow the development of high-performance chemiresistive sensors. However, the correlation between the morphologies and gas detection properties of tellurene has not yet been studied in depth, and few reports exist on tellurene-based hydrogen sulfide (H2S) chemiresistive sensors in spite of their strong interaction with H2S molecules. Here, we investigate the morphology-dependent H2S gas detection properties of tellurene synthesized using a hydrothermal method. To tailor the morphologies of tellurene, the molecular weight of the surfactant was controlled, revealing that a 1D or 2D form was synthesized and also accompanied with the high crystallinity. The 1D tellurene-based chemiresistive sensor presented superior H2S detection properties compared to the 2D form, achieving a gas response (Rg/Ra) of ~38, even at room temperature. This outstanding performance was attributed to the high intrinsic electrical conductivity and high specific surface area of the resultant 1D tellurene. [ABSTRACT FROM AUTHOR]

Understanding the reduction of CO2 and the origin and evolution of early life on Earth is an important research endeavor. Pyrite, due to its semiconductor properties, is believed to play a pivotal role as a reactant or catalyst in converting reducing gases, such as CO2, into organic matter. In this study, we employed density functional theory (DFT) to investigate the reduction of CO2 in the presence of H2S on the surface of pyrite. Our findings reveal that the presence of sulfur vacancies enhances the adsorption of H2S and CO2 molecules onto the pyrite surface. Interestingly, we observed the generation of the HCOOH molecule on the defective pyrite surface. Additionally, the transition state analysis indicates that H2S and CO2 molecules require the overcoming of an energy barrier (Ea) of 36.93 kJ/mol to form the HCOOH molecule. This study sheds light on the role of pyrite in the early creation of life on Earth by elucidating its impact on the reduction of carbon dioxide. [ABSTRACT FROM AUTHOR]

In the developed assay, multiorbital 3D DNA walker (MO DNA walker) was applied as signal amplified protocol for enhancing the detection signal of the photothermal biosensor, which was designed for sensitive detection of miRNA based on the H2S triggered conversation of photothermal reagent. When the target molecule is present, the DNA walking strand was released and then hybridize with track strands. The landing of walking particles (WPT) on the tracking particles (TPT) promotes the relative movement of the WPT around TPT, thus releasing large amount of horseradish peroxidase (HRP) with the aid of DNAzyme. After reacting with Na2S2O3 and H2O2, multiple H2S can be generated in situ based on the catalytic ability of HRP. Meanwhile, cubic Prussian blue (CPB) was synthesized and exhibited superior photothermal response, which can be served as efficient photothermal reagent and H2S responsive acceptor. Significantly, the photothermal signal of CPB could be obviously reduced after challenged with H2S ascribed to synchronous reaction between the ferric ion (Fe3+) and H2S. The improved walking area and freedom enable significant signal amplification, enhancing the biosensor's performance. Under ideal circumstances, the proposed photothermal assay demonstrated excellent performance for determination of miRNA-21. [ABSTRACT FROM AUTHOR]

Blue holes are submarine karst cavities with chemical and physical characteristics of the water column completely different from those in the surrounding environment. In this study a multi-parameter probe was used, for the first time, to characterise the water column of the Blue Hole of Faanu Madugau (Ari Atoll, Maldives, 3°55.799′ E 72°56.469′ N), the only blue hole described in the Indian Ocean up to date. Measurements of the temperature, salinity, dissolved oxygen, turbidity, chlorophyll-α, photosynthetically active radiation, potential density, pH, and H2S were obtained with a high detail. Three distinct physical–chemical layers were identified from the surface up to 70 m depth. An intermediate and turbid layer, located between 40 m and 46 m depth, sharply separates the upper layer displaying water characteristics equal to those of the outside environment from the deep and more characteristic layer of the blue hole, where a unique environment can be observed. Waters are oxygenated, warm, and rich in chlorophyll-α in the upper layer, whilst waters are anoxic, colder, denser, and completely dark, with low pH values and high H2S content in the deep layer. The Blue Hole of the Maldives represents an extreme environment from a geological, oceanographic, biological, and ecological point of view. Further investigations will be thus required to understand the origin of the Blue Hole waters, the mechanisms that keep it isolated from the external environment, the influence of weather and marine forcing on it, and how climate change may impact it. [ABSTRACT FROM AUTHOR]