• Biomolecules & Therapeutics
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• 제16권1호
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• pp.1-8
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• 2008

Mitochondria are important sensor of apoptosis. $H_2O_2-induced$ cell death rate was enhanced by serum deprivation. In this study, we investigated whether serum deprivation using 0.5 or 3 % FBS induces apoptotic cell death through mitochondrial enzyme activation as compared to 10 % FBS. Apoptotic cell death was observed by chromosome condensation and the increase of sub-G0/G1 population. Serum deprivation reduced cell growth rate, which was confirmed by the decrease of S-phase population in cell cycle. Serum deprivation significantly increased caspase-9 activity and cytochrome c release from mitochondria into cytosol. Serum deprivation-induced mitochondrial changes were also indicated by the increase of ROS production and the activation of mitochondrial enzyme, succinate dehydrogenase. Mitochondrial enzyme activity increased by serum deprivation was reduced by the treatment with rotenone, mitochondrial electron transport inhibitor. In conclusion, serum deprivation induced mitochondrial apoptotic cell death through the elevation of mitochondrial changes such as ROS production, cytochrome c release and caspase-9 activation. It suggests that drug sensitivity could be enhanced by the increase of mitochondrial enzyme activity in serum-deprived condition.

• BMB Reports
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• 제28권2호
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• pp.177-183
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• 1995

The activity of aldehyde dehydrogenase (ALDH) in the cerebrum, cerebellum, striatum, and medulla oblongata was examined and mitochondrial matrix ALDH was purified prior to immunohistochemical study on the localization of ALDH isozymes in pig brain. Relatively high enzyme activity was found in the striatum and medulla oblongata when using indole-3-acetaldehyde as substrate, and in the striatum when using 3,4-dihydroxyphenylacetaldehyde (DOPAL). The main part of mitochondrial ALDH activities with both acetaldehyde and DOPAL existed in the matrix fraction. The ratio of activity of the matrix to the membrane fraction in the cerebrum was higher than in the cerebellum, suggesting that the distribution pattern of ALDH isozymes was different according to the brain regions. The 276-fold purified mitochondrial matrix ALDH from pig brain was identified to be homologous tetramers with 53 KD subunits. The enzyme showed maximal activity at pH 9.0 and was stable in the temperature range from $25^{\circ}C$ to $37^{\circ}C$. The mitochondrial matrix ALDH activity was considerably inhibited by acetaldehyde in vitro. The $K_m$ values of the enzyme for acetaldehyde and propionaldehyde were 5.8 mM and 4.9 mM, respectively, whereas $K_m$ values for indole-3-acetaldehyde and DOPAL were 44 ${\mu}M$ and 1.6 ${\mu}M$, respectively. The $V_{max}/K_{m}$ ratio was the highest with DOPAL as compared with other substrates. These results suggested that mitochondrial matrix ALDH in the present work might be a low Km isozyme involved in biogenic aldehyde oxidation in pig brain.

• 한국균학회지
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• 제22권2호
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• pp.122-129
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• 1994

표고버섯의 mitochondria에 금속 chelating agent인 10 mM EDTA 및 10 mM o-Phe을 포함하는 10 mM Tris-HCl 완충용액(pH 7.5)으로 48시간 동안 각각 투석처리 하였을 때 mitochondria 내의 철 이온 함량이 투석처리를 하지 않은 대조구에 비하여 각각 74% 및 68% 감소되며, mitochondrial $F_1-ATPase$의 활성도는 대조구에 비하여 각각 56% 및 49%의 활성을 상실하였다. EDTA 투석에 의하여 활성을 상실한 metal-free mitochondrial $F_1-ATPase$는 $0.5\;mM\;Fe^{3+}$과 $0.05\;mM\;Mg^{2+}$에 의하여 각각 81% 및 70%의 활성이 회복되었으며, $Fe^{2+}$에 의해서는 활성이 회복되지 않았다. 또한 이 효소는 $0.5\;mM\;Fe^{3+}$와 $0.05\;mM\;Mg^{2+}$이 공존할 때 95%의 재활성화를 나타내었으며, $Fe^{2+}$와 $Mg^{2+}$의 공존 효과는 없었다. o-Phe으로 투석한 효소도 각 이온에 대하여 EDTA로 투석한 효소와 유사한 결과를 나타내었다. 그러므로, 표고버섯 내의 mitochondrial $F_1-ATPase$는 그 활성을 나타내는 데 있어서 $Fe^{3+}$ 및 $Mg^{2+}$을 필요로 함을 알았다. 기질 ATP에 대한 효소의 Km값은 1.67 mM이나, 효소를 가장 크게 활성화시키는 $0.5\;mM\;Fe^{3+}$와 $0.05\;mM\;Mg^{2+}$이 존재할 때의 Km값은 0.65 mM로서 기질 친화성이 증가되었다.

• 한국균학회지
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• 제21권3호
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• pp.165-171
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• 1993

표고버섯 중의 광감응성 mitochondrial ATP synthase는 0.1 mM $Fe^{2+}$ 단독 이온에 의하여 그 활성이 대조구에 비해 102%, 증가되었으며, 반면 $Fe^{3+}$ 및 $Mg^{2+}$ 이온은 효소의 활성을 억제시켰다. 0.5 mM $Mg^{2+}$ 존재하에서 0.1 mM $Fe^{2+}$ 이온에 의한 이 효소의 활성은 32% 증가되었으며 0.5 mM $Mg^{2+}$ 존재하에서 $Fe^{3+}$ 이온효과는 단독 $Fe^{3+}$ 이온의 효과와 유사한 경향으로 효소의 활성을 저해하였다. 0.5 mM $Mg^{2+}$과 0.1 mM, 0.5 mM 및 1.0 mM $Fe^{3+}$ 이온의 공존하에서$Fe^{2+}$ 이온에 의한 효소의 활성은 모두 억제되었으며, 특히 0.5 mM $Mg^{2+}$과 0.1 mM $Fe^{3+}$ 이온의 공존하에서 5.0 mM $Fe^{2+}$ 이온에 의하여 53%의 억제현상을 나타내었다. 따라서 표고버섯 중의 광감응성 mitochondrial ATP synthase의 활성은 $Fe^{2+}$ 이온에 의하여 특이적으로 크게 증가되며, 이 효소에 대한 $Fe^{2+}$ 이온의 활성화 효과가 $Mg^{2+}$ 이온에 의하여 크게 영항을 받지 않으나, $Fe^{3+}$ 이온의 공존하에서는 억제됨을 알았다. 활성화 금속이온인 $Fe^{2+}$ 존재하에서 이 효소의 최적 pH는 7.6이며, 최적 온도는 $63^{\circ}C$이었다. 또한 이 효소는 금속 chelating agent인 EDTA에 의하여 효소의 활성이 상실됨으로써 metalloenzyme의 가능성을 제시하였다.

• 한국균학회지
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• 제21권3호
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• pp.157-164
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• 1993

1. 표고버섯중 광감응성 mitochondrial $F_1-ATPase$는 $Fe^{3+},\;Fe^{2-}$ 및 $Mg^{2+}$ 이온에 의하여 각각 활성화 되었으나 5.0 mM $Fe^{3+}$ 이온에 의한 상대활성도는 대조구에 비하여 107% 증가시켰다. 2 $Mg^{2+}$ 존재하에서 $Fe^{3+}$ 및 $Fe^{2-}$ 각 이온 농도효과는 모두 효소의 활성을 증가시켰으나 0.1 mM $Mg^{2+}$과 5.0 mM $Fe^{3+}$ 이온의 공존하에서 170%를 증가시켜 $Mg^{2+}$ 이온에 의한 상승작용을 보였다. 3. 0.1 mM $Mg^{2+}$와 0.1 mM $Fe^{2+}$ 존재하에서 $Fe^{3+}$ 이온농도효과는 그 농도가 5.0 mM일 때 168%의 활성도 증가를 보여 $Fe^{2-}$ 이온공존효과는 없었다. 4. 이 효소는 $Mg^{2+}$ 및 $Fe^{3+}$ 이온에 의하여 활성화되는 특성을 가지고 있으며 활성금속이온 존재하에서 측정한 최적 pH 빛 온도는 각각 7.5 및 $66^{\circ}C$였다.

• 한국축산식품학회지
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• 제24권2호
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• pp.151-155
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• 2004

본 연구는 미토콘드리아 malate dehydrogenase활성을 이용하여 냉장계육과 냉동계육의 판별법을 개발하기 위하여 실시되었다. 단백질의 함량은 8.5mg/mL에서 12.7mg/mL 범위로 나타났으며, 동일 저장 기간 동안의 온도 별 차이점은 모든 부위에서 1일에서 15일 저장기간이 길어짐에 따라 단백질함량이 늘어나는 경향을 보인다. 냉장육의 보수력은 저장 기간 1일 60.5%에서 15일 33.9%로 감소하였으며 유의적 차이는 없었다(p＞0.05). 냉장계육과 냉동계육은 저장 기간이 길어짐에 따라 육즙손실량이 증가하였으며 유의적 차이는 없었다.(p＞0.05). 냉장계육의 육즙손실량이 냉동계육의 육즙손실량보다 낮게 나타났다. 냉장계육과 냉동계육 간의 mitochondrial malate dehydrogenase의 활성은 냉동계육이 냉장계육보다 효소활성이 높게 나타났다. 따라서 본 연구결과로부터 mitochondrial malate dehydrogenase의 활성 여부로 계육의 냉장, 냉동 유무를 판별하는데 유효한 지표로 사용 가능한 것으로 사료되었다.

• 한국환경성돌연변이발암원학회지
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• 제22권3호
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• pp.199-204
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• 2002

It has been known that Ganoderma lucidum and Lentinus edodes have anticancer activity and immune enhancing activity. These two mushrooms were grown in liquid culture and harvested. From these mycelia, DNA was isolated and EtBr-CsCl density gradient ultracentrifugation was performed to purify it further. Then mitochondrial DNA was isolated by bisbenzimide-CsCl density ultracentrifugaton. Mitochondrial DNA of Ganoderma lucidum was digested by restriction enzymes, EcoR I, Hind Ⅲ, and Pst I, then electrophoresed. It showed 12, 22, 4 fragments. Mitochondrial DNA of Lentinus edodes was digested by EcoR I. Electric pattern showed 6 fragments. 4 fragments had appeared by Pst 1 digested mitochondrial DNA. Hind ill couldn't digest mitochondrial DNA of Lentinus edodes. Mitochondrial DNA of fusants was isolated to compare to those of parents. The results showed that fusant P₂S₄has new, recombined mitochondrial DNA. But P₂S₄had the same DNA that Ganoderma lucidum had.

• 한국균학회지
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• 제17권4호
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• pp.177-183
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• 1989

1. 느타리버섯 중의 미토콘드리아는 설탕농도 44% 층에서 분리 정제되었다. 2. 파장 변화에 따른 mitochondrial ATP synthase의 활성도는 480nm의 빛이 조사될 때 가장 크게 증가되었다. 3. 최적 파장 480nm의 빛 조사 시간 변화에 따른 활성도는 15분 동안 조사하였을 때 가장 크게 증가하였다. 4. 위의 최적 빛 조사 조건에서 이 효소의 최적 pH는 7.5, 최적 온도는 $56^{\circ}C$였다. 5. 최적 광 조건에서 얻은 이 효소는 $Fe^{3+}$, $Fe^{2+}$ 그리고 $K^{+}$ 이온에 의하여 활성화 되었으나, $Na^{+}$ 이온에 의해서는 억제되었다.

• Archives of Pharmacal Research
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• 제26권11호
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• pp.951-959
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• 2003

A series of typical (chlorpromazine, haloperidol and thioridazine) and atypical (risperidone, quetiapine, clozapine and olanzapine) antipsychotics were tested for effects on integrated bioenergetic functions of isolated rat liver mitochondria. Polarographic measurement of oxygen consumption in freshly isolated mitochondria showed that electron transfer activity at respiratory complex I is inhibited by chlorpromazine, haloperidol, risperidone, and quetiapine, but not by clozapine, olanzapine, or thioridazine. Chlorpromazine and thioridazine act as modest uncouplers of oxidative phosphorylation. The typical neuroleptics inhibited NADH-coenzyme Q reductase in freeze-thawed mitochondria, which is a direct measure of complex I enzyme activity. The inhibition of NADH-coenzyme Q reductase activity by the atypicals risperidone and quetiapine was 2-4 fold less than that for the typical neuroleptics. Clozapine and olanzapine had only slight effects on NADH-coenzyme Q reductase activity, even at 200 $\mu$ M. The relative potencies of these neuroleptic drugs as inhibitors of mitochondrial bioenergetic function is similar to their relative potencies as risk factors in the reported incidence of extrapyramidal symptoms, including tardive dyskinesia (TD). This suggests that compromised bioenergetic function may be involved in the cellular pathology underlying TD.

• Parasites, Hosts and Diseases
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• 제21권1호
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• pp.41-48
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• 1983

The activity and distribution of aspartate aminotransferase (EC 2.6. 1. 1) and alanine aminotransferase (EC 2.6.1.2) in adult Fascicle hepatica have been studied. Fasciola hepatica was fractionated by differential centrifugation into nuclear, mitochondrial and cytosolic fractions. The activity of GOT and GPT was measured by the method of Reitman and Frankel. Isozyme patterns of those enzyme were also examined by DEAE-cellulose column chromatography. The results obtained were as follows; 1. The activity of aspartate and alanine aminotransferase was about 0.55 unit and 0.92 unit per 1g of Fascicle hepatica, respectively. 2. The activity of those enzymes was relatively low compared with those in mammalian tissues. 3. The distribution of aspartate aminotransferase in the subcellular organelles showed that 71% of the activity was in cytosolic, 24% in mitochondrial and 5% was in nuclear fraction. 4. About 22% of the total alanine aminotransferase activity was found in the mitochondrial fratstion, about 66% in the cytosolic fraction. 5. Aspartate aminotransferase from cytosolic fraction was separated into two types of isozymes, whereas alanine aminotransferase from cytosolic fraction gave only one active peak on DEAE-cellulose column chromatography.