Reactions of Seleno- and Sulfoamino Acids with Hydroperoxides<sup>*</sup>

Caldwell, Kenneth A.; Tappel, Al L.

doi:10.1021/bi00899a007

Cited by 76 publications

(24 citation statements)

References 19 publications

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“…E). In fact, higher concentrations of Met could even suppress the defects of cells lacking Pap1 (0.84 mM; data not shown), suggesting that Met can block H 2 O 2 toxicity by directly reacting with it in the S. pombe acidic media, something that has previously been reported (Caldwell and Tappel, ; Savige and Fontana, ; Brot and Weissbach, ; Vogt, ). This protective effect can also be observed by adding Cys to the growth media, even though the concentrations have to be higher to accomplish full suppression (Fig.…”

Section: Resultssupporting

confidence: 64%

Methionine sulphoxide reductases revisited: free methionine as a primary target of H₂O₂ stress in auxotrophic fission yeast

García-Santamarina

Boronat

Ayté

et al. 2013

Molecular Microbiology

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SummaryAmino acid methionine can suffer reversible oxidation to sulphoxide and further irreversible over-oxidation to methionine sulphone. As part of the cellular antioxidant scavenging activities are the methionine sulphoxide reductases (Msrs), with a reported role in methionine sulphoxide reduction, both free and in proteins. Three families of Msrs have been described, but the fission yeast genome only includes one representative for two of these families: MsrA/ Mxr1 and MsrB/Mxr2. We have investigated their role in methionine reduction and H 2O2 sensitivity. We show here that MsrA/Mxr1 is able to reduce free oxidized methionine. Cells lacking each one of the genes are not significantly sensitive to different types of oxidative stresses, neither display altered life span. However, only when deletion of msrA/mxr1 is combined with deletion of met6, which confers methionine auxotrophy, the survival upon H2O2 stress decreases by 100-fold. In fact, cells lacking only Met6, and which therefore require addition of methionine to the growth media, are extremely sensitive to H2O2 stress. These and other evidences suggest that oxidation of free methionine is a primary target of peroxide toxicity in cells devoid of methionine biosynthetic capacity, and that an important role of Msrs is to recycle this oxidized free amino acid.

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Section: Resultssupporting

confidence: 64%

Methionine sulphoxide reductases revisited: free methionine as a primary target of H₂O₂ stress in auxotrophic fission yeast

García-Santamarina

Boronat

Ayté

et al. 2013

Molecular Microbiology

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“…Selenium is present in foods mainly as the amino acids selenomethionine and selenocysteine. Selenium compounds are anti-oxidants that delete free radicals in vitro and improve the activity of the seleno-enzyme, glutathione peroxidase, which can prevent free radicals from damaging cells and tissues in vivo [17–19]. Recently, selenium nanoparticles have been used as additives in growth of corn and cereals as well as in vitamins replacing organic selenium compound to replenish the essential trace selenium in human’s body.…”

Section: Introductionmentioning

confidence: 99%

Facile Synthesis and Optical Properties of Small Selenium Nanocrystals and Nanorods

Jiang¹,

Cai

Tan³

2017

Nanoscale Res Lett

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Selenium is an important element for human’s health, small size is very helpful for Se nanoparticles to be absorbed by human's body. Here, we present a facile approach to fabrication of small selenium nanoparticles (Nano-Se) as well as nanorods by dissolving sodium selenite (Na2SeO3) in glycerin and using glucose as the reduction agent. The as-prepared selenium nanoparticles have been characterized by X-ray diffraction (XRD), UV-Vis absorption spectroscopy and high resolution transmission electron microscope (HRTEM). The morphology of small Se nanoparticles and nanorods have been demonstrated in the TEM images. A small amount of 3-mercaptoproprionic acid (MPA) and glycerin play a key role on controlling the particle size and stabilize the dispersion of Nano-Se in the glycerin solution. In this way, we obtained very small and uniform Se nanoparticles; whose size ranges from 2 to 6 nm. This dimension is much smaller than the best value (>20 nm) ever reported in the literatures. Strong quantum confinement effect has been observed upon the size-dependent optical spectrum of these Se nanoparticles.

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“…However, a number of these reagents require elevated temperatures, extended reaction times, or both. Similarly, a number of reagents, including hydrogen peroxide, DMSO, periodate, chloramine-T, N-chlorosuccinimide, and mild brominating agents have previously been employed for the deliberate oxidation of methionine residues within peptides and proteins [40][41][42][43][44][45][46][47][48][49]. Many of these reagents have also been shown to result in the oxidation of other amino acid residues, including tryptophan, cysteine, or histidine [41,[45][46][47][48][49][50][51][52][53].…”

Section: Introductionmentioning

confidence: 99%

The origin and control of ex vivo oxidative peptide modifications prior to mass spectrometry analysis

Froelich

Reid

2008

Proteomics

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The origin and control of ex vivo sample handling related oxidative modifications of methionine-, S-alkyl cysteine-, and tryptophan-containing peptides obtained from typical "in-solution" or "in-gel" proteolytic digestion strategies, have been examined by capillary HPLC and MS/MS. The origin of increased oxidation levels were found to be predominantly associated with the extensive ex vivo sample handling steps required for gel electrophoresis and/or in-gel proteolytic digestion of proteins prior to analysis by MS. Conditions for deliberately controlling the oxidation state (both oxidation and reduction) of these peptides, as well as for those containing cysteine, have been evaluated using a series of model synthetic peptides and standard tryptic protein digests. Essentially complete oxidation of methionine- and S-alkyl cysteine-containing peptides was achieved by reaction with 30% hydrogen peroxide/5% acetic acid at room temperature for 30 min. Under these conditions, cysteine was also converted to cysteic acid, while only limited oxidation of tryptophan to oxindolylalanine, and methionine and S-alkyl cysteine sulfoxides to their respective sulfones, were observed. Efficient reduction of methionine- and S-alkyl cysteine sulfoxide-containing peptides was achieved by reaction in 1 M dimethylsulfide/10 M hydrochloric acid at room temperature for 10 and 45 min, respectively. None of the reduction conditions evaluated were found to result in the reduction of oxindolylalanine, cysteic acid, or methionine sulfone.

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Reactions of Seleno- and Sulfoamino Acids with Hydroperoxides^*

Cited by 76 publications

References 19 publications

Methionine sulphoxide reductases revisited: free methionine as a primary target of H₂O₂ stress in auxotrophic fission yeast

Methionine sulphoxide reductases revisited: free methionine as a primary target of H₂O₂ stress in auxotrophic fission yeast

Facile Synthesis and Optical Properties of Small Selenium Nanocrystals and Nanorods

The origin and control of ex vivo oxidative peptide modifications prior to mass spectrometry analysis

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Reactions of Seleno- and Sulfoamino Acids with Hydroperoxides*

Cited by 76 publications

References 19 publications

Methionine sulphoxide reductases revisited: free methionine as a primary target of H2O2 stress in auxotrophic fission yeast

Methionine sulphoxide reductases revisited: free methionine as a primary target of H2O2 stress in auxotrophic fission yeast

Facile Synthesis and Optical Properties of Small Selenium Nanocrystals and Nanorods

The origin and control of ex vivo oxidative peptide modifications prior to mass spectrometry analysis

Contact Info

Product

Resources

About

Reactions of Seleno- and Sulfoamino Acids with Hydroperoxides^*

Methionine sulphoxide reductases revisited: free methionine as a primary target of H₂O₂ stress in auxotrophic fission yeast

Methionine sulphoxide reductases revisited: free methionine as a primary target of H₂O₂ stress in auxotrophic fission yeast