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Nature Chemical Biology Jan 2023Ferroptosis is a type of cell death caused by radical-driven lipid peroxidation, leading to membrane damage and rupture. Here we show that enzymatically produced sulfane...
Ferroptosis is a type of cell death caused by radical-driven lipid peroxidation, leading to membrane damage and rupture. Here we show that enzymatically produced sulfane sulfur (S) species, specifically hydropersulfides, scavenge endogenously generated free radicals and, thereby, suppress lipid peroxidation and ferroptosis. By providing sulfur for S biosynthesis, cysteine can support ferroptosis resistance independently of the canonical GPX4 pathway. Our results further suggest that hydropersulfides terminate radical chain reactions through the formation and self-recombination of perthiyl radicals. The autocatalytic regeneration of hydropersulfides may explain why low micromolar concentrations of persulfides suffice to produce potent cytoprotective effects on a background of millimolar concentrations of glutathione. We propose that increased S biosynthesis is an adaptive cellular response to radical-driven lipid peroxidation, potentially representing a primordial radical protection system.
Topics: Lipid Peroxidation; Ferroptosis; Cell Death; Free Radicals; Sulfur
PubMed: 36109647
DOI: 10.1038/s41589-022-01145-w -
Amino Acids Jun 2011
Topics: Amino Acids; Humans; Selenium; Sulfur
PubMed: 21547360
DOI: 10.1007/s00726-011-0930-2 -
Molecules (Basel, Switzerland) Apr 2023In recent years, researchers have been exploring the potential of incorporating selenium into peptides, as this element possesses unique properties that can enhance the... (Review)
Review
In recent years, researchers have been exploring the potential of incorporating selenium into peptides, as this element possesses unique properties that can enhance the reactivity of these compounds. Selenium is a non-metallic element that has a similar electronic configuration to sulfur. However, due to its larger atomic size and lower electronegativity, it is more nucleophilic than sulfur. This property makes selenium more reactive toward electrophiles. One of the most significant differences between selenium and sulfur is the dissociation of the Se-H bond. The Se-H bond is more easily dissociated than the S-H bond, leading to higher acidity of selenocysteine (Sec) compared to cysteine (Cys). This difference in acidity can be exploited to selectively modify the reactivity of peptides containing Sec. Furthermore, Se-H bonds in selenium-containing peptides are more susceptible to oxidation than their sulfur analogs. This property can be used to selectively modify the peptides by introducing new functional groups, such as disulfide bonds, which are important for protein folding and stability. These unique properties of selenium-containing peptides have found numerous applications in the field of chemical biology. For instance, selenium-containing peptides have been used in native chemical ligation (NCL). In addition, the reactivity of Sec can be harnessed to create cyclic and stapled peptides. Other chemical modifications, such as oxidation, reduction, and photochemical reactions, have also been applied to selenium-containing peptides to create novel molecules with unique biological properties.
Topics: Selenium; Peptides; Sulfur; Selenocysteine; Cysteine
PubMed: 37049961
DOI: 10.3390/molecules28073198 -
Plant Science : An International... Dec 2015Sulfur is an essential mineral nutrient for plants, therefore, the pathways of its uptake and assimilation have been extensively studied. Great progress has been made in... (Review)
Review
Sulfur is an essential mineral nutrient for plants, therefore, the pathways of its uptake and assimilation have been extensively studied. Great progress has been made in elucidation of the individual genes and enzymes and their regulation. Sulfur assimilation has been intensively investigated by -omics technologies and has been target of several genome wide genetic approaches. This brought a significant step in our understanding of the regulation of the pathway and its integration in cellular metabolism. However, the large amount of information derived from other experiments not directly targeting sulfur has also brought new and exciting insights into processes affecting sulfur homeostasis. In this review we will integrate the findings of the targeted experiments with those that brought unintentional progress in sulfur research, and will discuss how to synthesize the large amount of information available in various repositories into a meaningful dissection of the regulation of a specific metabolic pathway. We then speculate how this might be used to further advance knowledge on control of sulfur metabolism and what are the main questions to be answered.
Topics: Plants; Sulfur
PubMed: 26706053
DOI: 10.1016/j.plantsci.2015.09.014 -
Bioscience Reports Sep 2022Reactive sulfur species (RSS) have been recognized in the last two decades as very important molecules in redox regulation. They are involved in metabolic processes and,... (Review)
Review
Reactive sulfur species (RSS) have been recognized in the last two decades as very important molecules in redox regulation. They are involved in metabolic processes and, in this way, they are responsible for maintenance of health. This review summarizes current information about the essential biological RSS, including H2S, low molecular weight persulfides, protein persulfides as well as organic and inorganic polysulfides, their synthesis, catabolism and chemical reactivity. Moreover, the role of RSS disturbances in various pathologies including vascular diseases, chronic kidney diseases, diabetes mellitus Type 2, neurological diseases, obesity, chronic obstructive pulmonary disease and in the most current problem of COVID-19 is presented. The significance of RSS in aging is also mentioned. Finally, the possibilities of using the precursors of various forms of RSS for therapeutic purposes are discussed.
Topics: COVID-19; Humans; Hydrogen Sulfide; Sulfides; Sulfur
PubMed: 36039860
DOI: 10.1042/BSR20221006 -
Metal Ions in Life Sciences Mar 2020The non-metallic chemical element sulfur, 3216S , referred to in Genesis as brimstone and identified as element by Lavoisier, is the tenth most abundant element in the...
The non-metallic chemical element sulfur, 3216S , referred to in Genesis as brimstone and identified as element by Lavoisier, is the tenth most abundant element in the universe and the fifth most common element on Earth. Important inorganic forms of sulfur in the biosphere are elemental sulfur (S8), sulfate (SO2-4), and sulfide (S2-), sulfite (SO2-3), thiosulfate, (S2O23), and polythionates (S3O62-; S4O62-). Because of its wide range of stable oxidation states, from +6to -2, sulfur plays important roles in central biochemistry as a structural and redoxactive element and is intimately related to life on Earth. Unusual reaction pathways involving sulfur compounds become possible by the specific properties of this element. Sulfur occurs in all the major classes of biomolecules, including enzymes, proteins, sugars, nucleic acids, vitamin cofactors, and metabolites. The flexibility of these biomolecules follows from its versatile chemistry. The best known sulfur mineral is perhaps pyrite (Fool's gold), with the chemical formula, FeS2. Sulfur radical anions, such as [S3].-, are responsible for the intense blue color of lapis lazuli, one of the most desired and expensive artists' materials. In the microbial world, inorganic sulfur compounds, e.g., elemental sulfur and sulfate, belong to the most important electron acceptors. Studies on microbial sulfur metabolism revealed many novel enzymes and pathways and advanced the understanding on metabolic processes used for energy conservation, not only of the microbes, but of biology in general. Transition metal sulfur complexes display intriguing catalytic activities, they provide surfaces and complex cavities in metalloenzymes that activate inert molecules such as H2, CO, N2 or N2O, and they catalyze the transformations of numerous organic molecules. Both thiamine diphosphate- (ThDP) and S-adenosyl- L-methionine- (SAM) dependent enzymes belong to Nature's most powerful catalysts with a remarkable spectrum of catalytic activities. In conclusion, given sulfur's diverse properties, evolution made an excellent choice in selecting sulfur as one the basic elements of life.
Topics: Oxidation-Reduction; Sulfates; Sulfur
PubMed: 32851823
DOI: 10.1515/9783110589757-008 -
IUBMB Life Apr 2015Persulfide groups are chemically versatile and participate in a wide array of biochemical pathways. Although it is well documented that persulfurated proteins supply a... (Review)
Review
Persulfide groups are chemically versatile and participate in a wide array of biochemical pathways. Although it is well documented that persulfurated proteins supply a number of important and elaborate biosynthetic pathways with sulfane sulfur, it is far less acknowledged that the enzymatic generation of persulfidic sulfur, the successive transfer of sulfur as a persulfide between multiple proteins, and the oxidation of sulfane sulfur in protein-bound form are also essential steps during dissimilatory sulfur oxidation in bacteria and archaea. Here, the currently available information on sulfur trafficking in sulfur oxidizing prokaryotes is reviewed, and the idea is discussed that sulfur is always presented to cytoplasmic oxidizing enzymes in a protein-bound form, thus preventing the occurrence of free sulfide inside of the prokaryotic cell. Thus, sulfur trafficking emerges as a central element in sulfur-oxidizing pathways, and TusA homologous proteins appear to be central and common elements in these processes.
Topics: Cytoplasm; Oxidation-Reduction; Prokaryotic Cells; Sulfur
PubMed: 25913822
DOI: 10.1002/iub.1371 -
Essays in Biochemistry Aug 2023Bioleaching offers a low-input method of extracting valuable metals from sulfide minerals, which works by exploiting the sulfur and iron metabolisms of microorganisms to... (Review)
Review
Bioleaching offers a low-input method of extracting valuable metals from sulfide minerals, which works by exploiting the sulfur and iron metabolisms of microorganisms to break down the ore. Bioleaching microbes generate energy by oxidising iron and/or sulfur, consequently generating oxidants that attack sulfide mineral surfaces, releasing target metals. As sulfuric acid is generated during the process, bioleaching organisms are typically acidophiles, and indeed the technique is based on natural processes that occur at acid mine drainage sites. While the overall concept of bioleaching appears straightforward, a series of enzymes is required to mediate the complex sulfur oxidation process. This review explores the mechanisms underlying bioleaching, summarising current knowledge on the enzymes driving microbial sulfur and iron oxidation in acidophiles. Up-to-date models are provided of the two mineral-defined pathways of sulfide mineral bioleaching: the thiosulfate and the polysulfide pathway.
Topics: Iron; Metals; Minerals; Sulfur; Sulfides
PubMed: 37449416
DOI: 10.1042/EBC20220257 -
FEMS Yeast Research Jul 2021Sulfur is an essential component of various biologically important molecules, including methionine, cysteine and glutathione, and it is also involved in coping with...
Sulfur is an essential component of various biologically important molecules, including methionine, cysteine and glutathione, and it is also involved in coping with oxidative and heavy metal stress. Studies using model organisms, including budding yeast (Saccharomyces cerevisiae) and fission yeast (Schizosaccharomyces pombe), have contributed not only to understanding various cellular processes but also to understanding the utilization and response mechanisms of each nutrient, including sulfur. Although fission yeast can use sulfate as a sulfur source, its sulfur metabolism pathway is slightly different from that of budding yeast because it does not have a trans-sulfuration pathway. In recent years, it has been found that sulfur starvation causes various cellular responses in S. pombe, including sporulation, cell cycle arrest at G2, chronological lifespan extension, autophagy induction and reduced translation. This MiniReview identifies two sulfate transporters in S. pombe, Sul1 (encoded by SPBC3H7.02) and Sul2 (encoded by SPAC869.05c), and summarizes the metabolic pathways of sulfur assimilation and cellular response to sulfur starvation. Understanding these responses, including metabolism and adaptation, will contribute to a better understanding of the various stress and nutrient starvation responses and chronological lifespan regulation caused by sulfur starvation.
Topics: Anion Transport Proteins; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins; Saccharomycetales; Schizosaccharomyces; Schizosaccharomyces pombe Proteins; Sulfate Transporters; Sulfur
PubMed: 34279603
DOI: 10.1093/femsyr/foab041 -
Chemphyschem : a European Journal of... Dec 2022The energetics of sulfur-carbon interaction are studied using thermo-desorption and immersion microcalorimetry experiments. Sulfur is incorporated in meso- and...
The energetics of sulfur-carbon interaction are studied using thermo-desorption and immersion microcalorimetry experiments. Sulfur is incorporated in meso- and microporous carbons by impregnation either from the liquid phase or the vapor phase. Varying the temperature of impregnation enables to fill preferentially microporous domains (vapor impregnation) or both micro-meso-macro domains (liquid impregnation). The three carbons lead to similar immersion enthalpies per unit area for liquid sulfur. This suggests that they possess similar surface-liquid interactions and that liquid sulfur, below the polymerization temperature, wets the whole surface accessible to nitrogen.
Topics: Carbon; Adsorption; Sulfur; Nitrogen; Thermodynamics
PubMed: 36008355
DOI: 10.1002/cphc.202200416