• 한국초지학회:학술대회논문집
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• 한국초지조사료학회 2005년도 학술심포지엄, 제43회 학술발표회
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• pp.158-159
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• 2005

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2003년도 정기총회 및 학술발표회
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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.

• Journal of Microbiology
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• 제41권3호
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• pp.248-251
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• 2003

Glutathione (GSH) is an important factor in determining tolerance against oxidative stress in living organisms. It is synthesized in two sequential reactions catalyzed by ${\gamma}$-glutamylcysteine synthetase (GCS) and glutathione synthetase (GS) in the presence of ATP. In this work, the effects of three different oxidative stresses were examined on GSH content and GSH-related enzyme activities in the fission yeast Schizosaccharomyces pombe. GSH content in S. pombe was significantly enhanced by treatment with hydrogen peroxide, ${\beta}$-naphthoflavone (BNF) and tert-butylhydroquinone (BHQ). Simultaneously, they greatly induced GCS and GS activity. However, they did not have any effects on glutathione reductase activity. These results suggest that GCS and GS activities in S. pombe are up-regulated by oxidative stress.

• 한국초지학회:학술대회논문집
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• 한국초지조사료학회 2005년도 학술심포지엄, 제43회 학술발표회
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• pp.172-173
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• 2005

• 한국초지학회:학술대회논문집
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• 한국초지조사료학회 2003년도 제28회 정기총회, 제41회 학술발표회.심포지엄
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• pp.176-177
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• 2003

• Journal of Microbiology
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• 제42권3호
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• pp.233-238
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• 2004

Transcriptional regulation of the Schizosaccharomyces pombe y-glutamylcysteine synthetase (GCS) gene was examined using the two GCS-lacZ fusion plasmids pUGCS101 and pUGCS102, which harbor 607 bp and 447 bp upstream regions, respectively. The negatively-acting sequence was located in the -607 - -447 bp upstream region of the GCS gene. The upstream sequence responsible for induction by menadione(MD) and L-buthionine-(S, R)-sulfoximine (BSO) resides in the -607 - -447 bp region, whereas the sequence which codes for nitric oxide induction is located within the -447 bp region, measured from the translational initiation point. Carbon source-dependent regulation of the GCS gene appeared to be dependent on the nucleotide sequence within -447 bp region. The transcription factor Papl is involved in the induction of the GCS gene by MD and BSO, but not by nitric oxide. Induction of the GCS gene occurring due to low glucose concentration does not depend on the presence of Pap1. These data imply that induction by MD and BSO may be mediated by the Pap1 binding site, probably located in the -607 - -447 region, and also that the nitric oxide-mediated regulation of the S. pombe GCS gene may share a similar mechanism with its carbon-dependent induction.

• Journal of Plant Biotechnology
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• 제7권3호
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• pp.195-202
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• 2005

The effects of constituent amino acids of glutathione (GSH), glutamate (Glu), cysteine (Cys) and glycine (Gly), on GSH synthesis in lettuce seedlings were examined in this study. The GSH concentration of the seedlings was increased to 5.1-fold and 1.6-fold the concentration of the control in the first leaves and roots, respectively, by simultaneous application of these constituent amino acids (Glu+Cys+Gly) at 100 mg/l to the culture solution for two days. In the first leaves and roots of these seedlings, the concentration of GSH was 180.4 and 14.6 nmole/gFW, and non-essential amino acids including Glu, Cys and Gly occupied 93.2% and 84.0% of the total free amino acids, respectively. Application of Cys greatly increased the concentration of GSH in the roots, and application of 50 mg/l Cys increased it to 26.1-fold the concentration in the control. The activity of GSH synthetase was higher in the leaves than in the roots, whereas the activity of ${\gamma}$-glutamylcysteine synthetase was higher in the roots than in the leaves.

• 약학회지
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• 제53권6호
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• pp.314-320
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• 2009

We examined metabolic conversion of cysteine into glutathione (GSH) and taurine in rat liver under oxidative stress. Administration of tert-butylhydroperoxide (t-BHP) into the portal vein of male rats resulted in a rapid elevation of serum sorbitol dehydrogenase, alanine aminotransferase, and aspartate aminotransferase activities, which decreased gradually in 24 hr. Hepatic cysteine concentration was reduced in 3 hr, and recovered progressively, reaching a level greater than 200% of the normal value in 24 hr. GSH was increased both in liver and blood at 9 hr after t-BHP challenge, whereas hypotaurine or taurine was not altered. $\gamma$-Glutamylcysteine synthetase (GCS) activity was increased from 9 hr after t-BHP treatment, but protein expression of the GCS-heavy subunit was not changed in liver. Activity or expression of cysteine dioxygenase was not affected by t-BHP treatment. Taken together, these data show that an acute oxidant challenge to the rats may induce upregulation of cysteine availability and GCS activity, resulting in an enhancement of hepatic GSH synthesis, but the increased cysteine level does not stimulate taurine synthesis via cysteine sulfinate pathway. It is indicated that the regulation of GSH and taurine biosynthesis from cysteine is not solely dependent on the cysteine concentration in rat liver under oxidative stress.

• 생명과학회지
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• 제7권4호
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• pp.253-261
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• 1997

E. coli에서 글루타치온 생산 증가를 위해서 E. coli에서 분리한 gehI과 gshII유전자를 함유하고 있는 여러 재조합 플라스미드를 구성하여 도입하였다.pBR325 벡터에 gehI 유전자를 각각 1-3개를 포함한 재조합 플라스미드 및 gehI과 gehII 유전자를 동시에 갖는 재조합 플라스미드를 구성하였다. 계속적으로 반복된 gehI 유전자가 증폭된 E. colidml $\gamma $-gluramylcysteine synthetase의 효소활성은 삽입된 gehI 유전자의 부에 따라 증가하였다. 구성된 재조합 플라스미드를 함유한 E.coli의 글루타치온 생산능을 accetate kinase반응을 ATP재생계로 사용하여 조사한 결과 반복된 gehI 유전자를 함유한 E.coli의 글루타치온 생산능력은 삽입된 gehI 유전자의 수에 비례한여 증가하였으며, gehI 유전자의 추가적인 도입에 의해 글루타치온 생산능력은 2배 증가하였다. E.coli에서 글루타치온의 효소적 생산은 주로 \gamma $-gluramylcysteine synthetase의 효소활성에 의해 영향을 받았다. 가장 높은 글루타치온 생산능은 pGH501 (pUC8-gsh.I.II.III) 플라스미드를 갖는 균주에서 관찰되었다.

• Preventive Nutrition and Food Science
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• 제4권4호
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• pp.260-264
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• 1999

Korean traditional fermented soy paste (doenjang) prolonged the life span of Balb/c mice injected with the sarcoma-180 cells. The activities of liver enzymes, such as xanthine oxidase, aminopyrine N-demethylase, aniline hydroxylase, ${\gamma}$-glutamylcysteine synthetase, glutathione reductase and glutathione S-transferase (GST), and the contents of lipid peroxide and glutathione were determined from the sarcoma-180 cell injected mice that were treated with methanol extracts from doenjang, miso and soybean. The content of lipid peroxide and the activity of xanthine oxidase in the liver of Balb/c mice which were increased by the transplantation of the sarcoma-180 cells were decreased by treatment with the methanol extract from doenjang. But the activities of aminopyrine N-dementhylase and aniline hydroxylase were not affected by the treatment of methanol extracts from doenjang to the mice injected with the sarcoma-180 cells. The content of glutathione, the activities of glutamylcysteine synthetase, glutathione reductase and glutathione S-transferase decreased by the injection of the sarcoma-180 were recovered considerably by the treatment of the methanol extract from doenjang.