349-46-2Relevant articles and documents
The L-cysteine/L-cystine shuttle system provides reducing equivalents to the periplasm in Escherichia coli
Ohtsu, Iwao,Wiriyathanawudhiwong, Natthawut,Morigasaki, Susumu,Nakatani, Takeshi,Kadokura, Hiroshi,Takagi, Hiroshi
, p. 17479 - 17487 (2010)
Intracellular thiols like L-cysteine and glutathione play a critical role in the regulation of cellular processes. Escherichia coli has multiple L-cysteine transporters, which export L-cysteine from the cytoplasm into the periplasm. However, the role of L-cysteine in the periplasm remains unknown. Here we show that an L-cysteine transporter, YdeD, is required for the tolerance of E. coli cells to hydrogen peroxide. We also present evidence that L-cystine, a product from the oxidation of L-cysteine by hydrogen peroxide, is imported back into the cytoplasm in a manner dependent on FliY, the periplasmic L-cystine-binding protein. Remarkably, this protein, which is involved in the recycling of the oxidized L-cysteine, is also found to be important for the hydrogen peroxide resistance of this organism. Furthermore, our analysis of the transcription of relevant genes revealed that the transcription of genes encoding FliY and YdeD is highly induced by hydrogen peroxide rather than by L-cysteine. These findings led us to propose that the inducible L-cysteine/L-cystine shuttle system plays an important role in oxidative stress tolerance through providing a reducing equivalent to the periplasm in E. coli.
Peroxidase-mimicking DNAzyme modulated growth of CdS nanocrystalline structures in situ through redox reaction: Application to development of genosensors and aptasensors
Garai-Ibabe, Gaizka,M?ller, Marco,Saa, Laura,Grinyte, Ruta,Pavlov, Valeri
, p. 10059 - 10064 (2014)
This work demonstrates the use of the peroxidase-mimicking DNAzyme (peroxidase-DNAzyme) as general and inexpensive platform for development of fluorogenic assays that do not require organic fluorophores. The system is based on the affinity interaction between the peroxidase-DNAzyme bearing hairpin sequence and the analyte (DNA or low molecular weight molecule), which changes the folding of the hairpin structure and consequently the activity of peroxidase-DNAzyme. Hence, in the presence of the analyte the peroxidase-DNAzyme structure is disrupted and does not catalyze the aerobic oxidation of l-cysteine to cystine. Thus, l-cysteine is not removed from the system and the fluorescence of the assay increases due to the in situ formation of fluorescent CdS nanocrystals. The capability of the system as a platform for fluorogenic assays was demonstrated through designing model geno- and aptasensor for the detection of a tumor marker DNA and a low molecular weight analyte, adenosine 5triphosphate (ATP), respectively.
Preparation method of high-purity D-cystine
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Paragraph 0017-0030, (2021/02/06)
The invention discloses a preparation method of high-purity D-cystine. The preparation method comprises the following steps: hydrolyzing D-2, 2-dimethyltetrahydrothiazole-4-carboxylic acid.L-tartrate,and converting the hydrolysate, specifically, converting L-tartaric acid in the hydrolysate into Lentinite, which is separated out as a precipitate; then, before the filtrate is oxidized, the pH value of the filtrate is firstly reduced so that introduction of more impurities in the oxidation process is reduced, and high-purity and high-yield D-cysteine is obtained; the whole preparation method issimple in production process, safe in used raw materials, easy to control, free of high-temperature and high-pressure reaction, low in equipment investment and easy to produce and operate.
S-aroylthiooximes: A facile route to hydrogen sulfide releasing compounds with structure-dependent release kinetics
Foster, Jeffrey C.,Powell, Chadwick R.,Radzinski, Scott C.,Matson, John B.
supporting information, p. 1558 - 1561 (2014/04/17)
We report the facile preparation of a family of S-aroylthiooxime (SATO) H2S donors, which are synthesized via a click reaction analogous to oxime formation between S-aroylthiohydroxylamines (SATHAs) and aldehydes or ketones. Analysis of cysteine-triggered H2S release revealed structure-dependent release kinetics with half-lives from 8-82 min by substitution of the SATHA ring. The pseudo-first-order rate constants of substituted SATOs fit standard linear free energy relationships (p = 1.05), demonstrating a significant sensitivity to electronic effects.
