• Microbiology and Biotechnology Letters
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• v.13 no.2
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• pp.137-144
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• 1985

Studies were conducted on the conditions for preparation of yeast protoplasts utilizing Hansenula anomala var. anomala FRI YO-32 as well as Saccharomyces cerevisiae KFCC 32356 and a lytic enzyme from the snail Helix pomatia. The cell wails of the strain FRI YO-32 and S cerevisiae were found to be resistant to activity of the snail lytic enzyme if they were not treated with thiol compounds. Dithiothreitol was found to be more effective than 2-mercaptoethanol, but the latter was considered to be practical. As factors influencing the formation of yeast protoplast, it was considered to be concentration and incubation time of 2-mercaptoethanol or the lytic enzyme, growth stages in yeast cultivation, initial number of yeast cells, and concentration of osmotic stabilizer (KCI). Optimum conditions for the preparation of yeast protoplasts were determined.

• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.555-561
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• 1990

Aromas of sulfur-containing volatiles from two vegetable varieties of Cruciferae Brassica oleracea and the suppression of undesirable sulfurous aromas of cruciferous vegetables by sulfhydryl oxidase of caraway seeds were examined. Aroma components were separated by gas chromatography equipped with a dual flame photometric detector The volatile sulfides produced from cabbage and broccoli varied. in the relative quantities and rates of production. according to the amount of caraway seeds added and incubation time. The amount of methanethiol and dimethyl disulfide in the cabbage and broccoli with caraway seeds was far less than those in the cabbage and broccoli. Removal of methanethiol and dimethyl disulfide was proportional to the amount of caraway seeds added, and was remarkable with 2.5% aqueous slurries of caraway seeds added.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.61-61
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• 2003

We have cloned the CGR1 gene encoding glutathione reductase (GR) which catalyzes the reduction of oxidized glutathione (GSSG) to reduced glutathione (GSH) from Candida albicans. The cgr1/cgr1 mutants were not viable when CaMAL2 promoter repressed the CGR1 expression. The growth of the mutants could be partially overcome by thiol compounds such as GSH, dithiothreitol, cysteine, N-acetylcysteine and GSSG. Interestingly, C. albicans with CGR1 overexpressed showed defective hyphal growth on solid medium and attenuated virulence. We have also cloned the GCS1 gene encoding ${\gamma}$-glutamylcysteine synthetase which catalyzes the first step of glutathione biosynthesis. The gcs1/gcs1 mutants were nonviable in minimal defined medium. The growth of the mutants could be resumed by supplementing with GSH, GSSG and ${\gamma}$-glutamylcysteine in the medium. The mutants had increased intracellular D-erythroascorbic acid level up to 2.25-fold when transferred to GSH-free medium. When the mutants were depleted of GSH, they showed typical markers of apoptosis. In conclusion, these results suggest that glutathione is an essential metabolite, and involved in hyphal growth, virulence and apoptosis in C. albicans.

• Archives of Pharmacal Research
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• v.28 no.2
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• pp.216-219
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• 2005

Wogonin (5,7-dihydroxy-8-methoxyflavone) has been reported to exhibit a variety of biological properties including anti-inflammatory and neuroprotective functions. In this study, biological activities of diverse synthetic wogonin derivatives have been evaluated in two experimental cell culture models. Inhibitory activities of wogonin derivatives on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in BV2 microglial cells and on hydrogen peroxide ($H_{2}O_2$)-induced neuronal cell death in SH-SY5Y human neuroblastoma were examined. Wogonin derivatives such as WS2 and WS3 showed more potent suppressive activities on LPS-induced NO production and $H_{2}O_2$-induced cytotoxicity than wogonin itself. In addition, thiol substitution played a minor role in enhancing the activities of the derivatives. These findings may contribute to the development of novel anti-inflammatory and neuroprotective agents derived from wogonin.

• Journal of the Korean Chemical Society
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• v.16 no.6
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• pp.334-340
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• 1972

CNDO/2 calculations have been carried out on methyl chloro-thiol-, methyl chloro-thiono-, and methyl chloro-dithio-formates. Results show that the trans is the stable configuration for these compounds. It was found that sulfur atom has much less tendency to use its lone pair electrons for ${\pi}$ bond formation compared with oxygen, and that thiolformates are stabilized by hyperconjugation of methyl hydrogens. The order of solvolytic reactivity was found to follow the order of cation stability, which is consistent with the $S_N1$ mechanism proposed for these compounds.

• Journal of Environmental Health Sciences
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• v.19 no.1
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• pp.66-70
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• 1993

Introduction : Methanethiol is a toxicant that is a byproduct in the industrial process (oil refinery), and it is produced in vivo from methionine via transamination in case of its overintake. And it also can be generated by the action of mucosal thiol Smethyltransferase on hydrogen sulfite which is formed by anaerobic bacteria in the intestinal tract. The toxicity of methanethiol has often been suggested as one of endogenous factors involved in the pathogenesis of hepatic encephalopathy. Furthermore, methanethiol could cause the membrane damage and inhibition of some membrane protective enzymes.

• Journal of Periodontal and Implant Science
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• v.23 no.3
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• pp.517-525
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• 1993

Glutathione(GSH),a tripeptide thiol, found in virtually all cells, functions in metabolism tranasport and cellular protection. It protects cells against the destructive effects of reactive oxygen intermediates and free radicals. Also ${\gamma}-Glutamyl$ transpeptidase(${\gamma}-GTT$), an enzyme of major importance in GSH metabolism, initiates GSH degradation. In order to explore the $GSH-{\gamma}-GTT$ system as periodontal disease activity indicator, we observed the ${\gamma}-GTT$ and arachidonic acid metabolits according to clinical groups(Control, Adult periodontitis, Rapidly progressive Periodontitis). From the experiments, the following results were obtained. 1. When compared with normal, ${\gamma}-GTT$ of A. P. and R. P. P. were increased, and only the change of ${\gamma}-GTT$ of R. P. P. was statistically significant(P<0. 05). 2. The amounts of arachidonic acid metabolites were not different with statistical significance among the clinical groups. 3. ${\gamma}-GTT$ may by useful adjuncts as new cytoprotective indicator and periodontal disease activity indicator in accordance with positive corelation pocket depth, attachment level and ${\gamma}-GTT$.

• BMB Reports
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• v.33 no.6
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• pp.514-518
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• 2000

Two open reading frames of Haemophilus influenzae, HI0572 and HI0751, showing homology to a yeast thioredoxin peroxidase II (TPx II) and an E. coli thiol peroxidase $P_{20}$, respectively, were cloned and expressed in E. coli, and then the proteins were subsequently purified and characterized. HI0751 protein showed the thioredoxin (Trx)-dependent peroxidase activity, whereas HI0572 protein showed glutathione-dependent peroxidase. The HI0572 is the first peroxiredoxin with glutathione peroxidase activity rather than thioredoxin peroxidase. Purified HI0572 and HI0751 proteins protected specifically the inactivation of glutamine synthetase by metal catalyzed oxidation (MCO) systems composed of $Fe^{3+}$, $O_2$ and mercaptans such as dithiothreitol, ${\beta}-mercaptoethanol$ and glutathione (GSH). Unlike the HI0751 protein, the HI0572 protein was more effective in protecting glutamine synthetase from inactivation by the $GSH/Fe^{3+}/O_2$ system. It seems that these unique properties of the HI0572 protein are due to the structure containing a glutaredoxin domain at it's C-terminal in addition to a peroxiredoxin domain.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3583-3587
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• 2010

Furoxanthiols PFT and BPFT possessing thiomethyl or thiobenzyl groups in the furoxan ring were designed and synthesized as potential light-sensitive alkyne precursors on a gold surface. The synthesis of thiofuroxans PFT and BPFT was performed from the corresponding halofuroxans 1b and 2c, respectively, by the substitution with potassium thioacetate in ethyl acetate/ethanol or DMF, followed by basic hydrolysis as the key reactions. Electron-beammediated fragmentation of furoxans 1c and 2d in a mass spectrometer afforded the corresponding aryl alkyne fragments, with the evolution of NO in high preference. In the cases of thiofuroxans PFT and BPFT, carbon-sulfur bond cleavage was observed as a representative fragmentation, producing M-SH and M-SAc peaks, which competed with the release of NO. In the fragmentation of mono-aryl furoxan 1c, the release of molecule of NO was predominately observed to produce an M-NO fragment as a base peak by the formation of trimembered thiiranium or azirine intermediate.

• Bulletin of the Korean Chemical Society
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• v.30 no.11
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• pp.2574-2576
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• 2009

In this work, we describe a new sensor that specifically responds to biothiols, i.e., glutathione (GSH), in solution. An electrochemical transducing strategy was utilized and cyclic voltammetry (CV) was employed to monitor the presence of GSH in real time. Our approach harnessed self-assembled monolayers (SAMs) on gold consisting of an alkanethiolate which was terminated by electroactive quininoid moiety. Prior to thiol molecule treatment, the characterisitc reversible redox peaks of the electroactive quininoid group was observed, while the reduction peak was dramatically shifted upon a treatment of GSH. This sensor showed the capability to detect the GSH in solution in the range of 1 mM $\sim$ 100 aM. We believe that this strategy will provide an important tool for accurate, sensitive, rapid, and low-cost determination of GSH.