• Journal of Microbiology and Biotechnology
• /
• 제4권3호
• /
• pp.159-164
• /
• 1994

Myceliuml growth and spore formation of Streptomyces albidoflavus SMF301 in submerged culture were compared with the metabolism of cysteine. Cysteine added to the culture was metabolized by cysteine desulfhydrase (EC 4.4.1.1.) to produce ammonium ions, hydrogen sulfide, and pyruvate. The redox potential of the culture broth was lowered immediately as the result of the metabolism of cysteine, which caused a lag period of mycelium growth. However enhanced activities of pyruvate dehydrogenase and a-ketoglutarate dehydrogenase were confirmed in the culture containing cysteine, indicating that pyruvate was utilized to support further mycelium growth.

• 한국식품영양과학회지
• /
• 제24권6호
• /
• pp.978-983
• /
• 1995

The effect of sulfur-containing amino acids on lipid metabolism was studied in rats fed casein as a protein source. Plasma cholesterol, HDL-cholesterol and atherosclerotic index decreased in the cysteine group compared to the methionine group. Plasma triglyceride and phospholipid level were not affected by the supplementation of the sulfur-containing amino acids. The levels of cholesterol and triglyceride in liver decreased by both methionine and cysteine. Cysteine increased the fecal excretion of coprostanol, total neutral steroid and bile acid. The results suggest that plasma cholesterol level is affected by dietary ratio of cysteine/methionine and that the hypocholesterolemic effects of cysteine is, at least in part, through reducing cholesterol absorption from small intestine and through enhancing fecal excretion of bile acids.

• 약학회지
• /
• 제51권6호
• /
• pp.383-388
• /
• 2007

It has been reported that sulfur-containing intermediates or products in the transsulfuration pathway including S-adenosylmethionine, 5'-methylthioadenosine, glutathione and taurine can prevent liver injury mediated by inflammation response induced by lipopolysaccharide (LPS) treatment. The present study examines the modulation of hepatic metabolism of sulfur amino acid in a model of acute sepsis induced by LPS treatment (5 mg/kg, iv). Serum TNF-alpha and hepatotoxic parameters were significantly increased in rats treated with LPS, indicating that LPS results in sepsis at the doses used in this study. LPS also induced oxidative stress determined by increases in malondialdehyde levels and decreases in total oxy-radical scavenging capacities. Hepatic methionine and glutathione concentrations were decreased, but S-adenosylho-mocysteine, cystathionine, cysteine, hypotaurine and taurine concentrations were increased. Hepatic protein expression of methionine adenosyltransferase, cystathionine beta-synthase and cysteine dioxygenase were induced, but gamma-glutamylcysteine ligase catalytic subunit levels were decreased. The results show that sepsis activates transsulfuration pathway from methionine to cysteine, suggesting an increased requirement for methionine during sepsis.

• 약학회지
• /
• 제53권2호
• /
• pp.74-77
• /
• 2009

Food deprivation decreases hepatic glutathione (GSH) levels, which is ascribed to alterations in availability of hepatic cysteine, a rate limiting factor for the GSH synthesis. The present study examines the effects of food deprivation on hepatic metabolism of sulfur amino acid in male rats. In rats fasted for 24 or 48 hours, hepatic GSH levels were decreased from $6.70{\pm}0.16{\mu}mol/g$ liver to $4.02{\pm}0.20$ or $4.06{\pm}0.07{\mu}mol/g$ liver, respectively. Hepatic S-adenosylmethionine levels were also decreased in fasted rats, but S-adenosylhomocysteine levels were increased. Hepatic methionine levels were not changed by food deprivation for 48 hours. On the other hand, hepatic cysteine or taurine levels were increased from $106.2{\pm}4.1$ to $130.0{\pm}2.7$ nmol/g liver or from $2.45{\pm}0.43$ to $5.07{\pm}0.78{\mu}mol/g$ liver, respectively, in 48-hour fasted rats. Activity of cystathionine beta-synthase catalyzed homocysteine to cystathionine, was markedly decreased, but activity of betaine homocysteine methyltransferase was increased in fasted rats, indicating that methylation of homocysteine to methionine is activated. Also activity of cysteine dioxygenase, involved in taurine synthesis, was increased. These results suggested that hepatic methionine levels were maintained in rats fasted for 48 hours through increase in homocysteine methylation, and hepatic GSH may serve as a cysteine supplier reservoir in fasting state.

• 한국식품영양학회지
• /
• 제23권3호
• /
• pp.361-367
• /
• 2010

Streptozotocin(STZ)으로 유도된 당뇨 쥐에서 마늘, 양파 등 Allium 속(屬) 식물에 함유되어 있는 N-acetyl cysteine(NAC), S-allyl cysteine(SAC), S-ethyl cysteine(SEC) 및 S-methyl cysteine (SMC) 등 organocysteine 화합물이 혈당과 포도당 내성 및 혈장과 간 조직의 지질 농도에 미치는 영향을 살펴보았다. NAC, SAC, SEC 및 SMC 등 cysteine 화합물 투여는 STZ 당뇨로 인한 다음, 다식, 다뇨 및 체중 감소 증세를 일부 개선시키고, 내당능을 향상시키는 결과를 보였다. 당뇨 쥐에 있어서 cysteine 화합물의 투여는 혈장 총 콜레스테롤과 중성지질 농도에는 큰 영향을 미치지 않았으나, HDL-cholesterol의 농도의 증가와 LDL-cholesterol 농도의 감소를 통해 전반적으로 동맥경화 유발지수를 개선시키는 결과를 보였으며, 간 조직 중성지질 농도를 낮추어 당뇨군의 지방간 증세를 완화시킴과 아울러 혈장 GOT, GPT 활성을 감소시켜 간 보호 효과를 보였다. 이들 결과를 볼 때 NAC, SAC, SEC 및 SMC 등 cysteine 화합물은 STZ에 의해 유도된 당뇨 쥐에 있어 당대사 조절과 함께 지질대사 조절을 통해 지질대사 이상으로 인한 합병증 유발을 완화시킬 수 있는 가능성이 있다고 사료된다.

• 약학회지
• /
• 제53권2호
• /
• pp.69-73
• /
• 2009

Acute betaine treatment induces time-dependent changes in the hepatic glutathione (GSH), cysteine and S-adenosylmethionine (SAM) levels. Our previous study demonstrated that betaine administered $1{\sim}4$ hours prior to sacrifice decreased hepatic GSH levels, but these levels were increased when measured 24 hours following the treatment. The present study was aimed to determine dose-dependent effects of betaine on hepatic metabolism of sulfur amino acid in mice. Mice were sacrificed 2.5 or 24 hours after intraperitoneal treatment with betaine at different dose levels ranging from 50 to 1000 mg/kg. The concentrations of methionine and SAM were increased by a betaine dose of 100 mg/kg, and the concentrations of GSH and cysteine were decreased by a betaine dose of 200 mg/kg at 2.5 hours. These changes were augmented with increasing doses of betaine. At 24 hours following betaine treatment, increased GSH and decreased taurine levels were observed from dose levels of 400 mg/kg. Changes in hepatic activities of cystathionine beta-synthase, gammaglutamylcysteine ligase and cysteine dioxygenase were observed from dose levels of $200{\sim}400$ mg/kg of betaine administered 24 hours prior to sacrifice.

• Journal of Nutrition and Health
• /
• 제29권7호
• /
• pp.729-737
• /
• 1996

Activieties of hepatic cysteine desulfhydration was assessed in cats fed one of the following diets for 5 weeks : 20% protein, 0% taurine diet(LPOT) ; 20% protein, 0.15% taurine diet (LPNT) ; 60% protein, 0% taurine diet(HPOT) ; and 60% protein, 0.15% taurine diet(HPNT). Cats fed LPOT and HPOT had been maintained on a taurine-free diet for 6 weeks prior to the experiment in order to deplete body taurine. Activities of cysteine desulfhydration were determined by measuring the production of H235S from 35S-cysteine in the presence and absence of $\alpha$-ketoglutarate ($\alpha$-KG) in the incubation medium. The direct pathway via cysteine desulfhydrase appears to account for the major route of cysteine desulfhydration in the cat liver since the values obtained in the absence of $\alpha$-KG were between 81 and 88% of those obtained in the presence of $\alpha$-KG. Mean$\pm$SEM of the hepatic total desulfhydration activities(umol H2S.min-1.kg body wt-1)in cats fed LPOT, LPNT, HPOT and HPNT were 117$\pm$6, 135$\pm$10, 137$\pm$10, and 190$\pm$9, respectively. The capacity of hepatic cysteine desulfhydration (UA/kg body wt) was positively cerrelated not only with the dietary concentration of taurine but also with the concentration of protein.

• 한국미생물·생명공학회지
• /
• 제15권5호
• /
• pp.361-367
• /
• 1987

DL-seleno-methionine에 내성을 갖는 변이주, Cephalosporium acremonium MS-92는 무기황과 메치오닌의 Uptake rate가 모균보다 우수하였으며, 세포내에 과량의 메치오닌과 S-adenosylmethionine (SAM)을 축적하였다. 또 C. acremonium에서 무기황의 uptake rate는 시스테인에 의해 크게 저해되었다. Crude enzymes extracts에서 변이주 MS-92 는 cell내에 cysteine을 적게 형성하였다 즉, L.-serine sulfhydrylase 활성이 모균보다 낮았으며 세포내에 시스테인의 양을 간접적으로 알 수 있는 시스테인 분해효소인 cysteine desulfhydrylase 활성치 변이주에는 모균의 약 반이였다. 이상의 결과에서 C. acremonium에서 메치오닌을 만드는 효소들의 조절에는 A. nidulans와 비슷하게 시스테인이 관여한다는 것을 추측할 수 있었다.

• Biomolecules & Therapeutics
• /
• 제26권2호
• /
• pp.167-174
• /
• 2018

Alterations in sulfur amino acid metabolism are associated with an increased risk of a number of common late-life diseases, which raises the possibility that metabolism of sulfur amino acids may change with age. The present study was conducted to understand the age-related changes in hepatic metabolism of sulfur amino acids in 2-, 6-, 18- and 30-month-old male C57BL/6 mice. For this purpose, metabolite profiling of sulfur amino acids from methionine to taurine or glutathione (GSH) was performed. The levels of sulfur amino acids and their metabolites were not significantly different among 2-, 6- and 18-month-old mice, except for plasma GSH and hepatic homocysteine. Plasma total GSH and hepatic total homocysteine levels were significantly higher in 2-month-old mice than those in the other age groups. In contrast, 30-month-old mice exhibited increased hepatic methionine and cysteine, compared with all other groups, but decreased hepatic S-adenosylmethionine (SAM), S-adenosylhomocysteine and homocysteine, relative to 2-month-old mice. No differences in hepatic reduced GSH, GSH disulfide, or taurine were observed. The hepatic changes in homocysteine and cysteine may be attributed to upregulation of cystathionine ${\beta}-synthase$ and down-regulation of ${\gamma}-glutamylcysteine$ ligase in the aged mice. The elevation of hepatic cysteine levels may be involved in the maintenance of hepatic GSH levels. The opposite changes of methionine and SAM suggest that the regulatory role of SAM in hepatic sulfur amino acid metabolism may be impaired in 30-month-old mice.

• Parasites, Hosts and Diseases
• /
• 제56권1호
• /
• pp.1-9
• /
• 2018

Giardia lamblia, an anaerobic, amitochondriate protozoan parasite causes parasitic infection giardiasis in children and young adults. It produces pyruvate, a major metabolic product for its fermentative metabolism. The current study was undertaken to explore the effects of pyruvate as a physiological antioxidant during oxidative stress in Giardia by cysteine-ascorbate deprivation and further investigation upon the hypothesis that oxidative stress due to metabolism was the reason behind the cytotoxicity. We have estimated intracellular reactive oxygen species generation due to cysteine-ascorbate deprivation in Giardia. In the present study, we have examined the effects of extracellular addition of pyruvate, during oxidative stress generated from cysteine-ascorbate deprivation in culture media on DNA damage in Giardia. The intracellular pyruvate concentrations at several time points were measured in the trophozoites during stress. Trophozoites viability under cysteine-ascorbate deprived (CAD) medium in presence and absence of extracellular pyruvate has also been measured. The exogenous addition of a physiologically relevant concentration of pyruvate to trophozoites suspension was shown to attenuate the rate of ROS generation. We have demonstrated that Giardia protects itself from destructive consequences of ROS by maintaining the intracellular pyruvate concentration. Pyruvate recovers Giardia trophozoites from oxidative stress by decreasing the number of DNA breaks that might favor DNA repair.