• BMB Reports
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• 제30권2호
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• pp.138-143
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• 1997

In order to assess controversial' proposals concerning the fatty acid-induced uncoupling of mitochondrial oxidative phosphorylation, we investigated the interaction of stearic acid with key mitochondrial proteins and measured the effect of stearic acid on the respiration of cytochrome c oxidase vesicles. Electron paramagnetic resonance spectra of spin-labeled stearic acid clearly demonstrated that cytochrome c oxidase interacts strongly with stearic acid. However, the respiration of detergent-solubilized cytochrome c oxidase was not altered significantly by stearic acid. Surprisingly, adenine nucleotide carrier, which was assumed to bind and translocate fatty acid anions in the Skulachev model of uncoupling, did not bind stearic acid at all. The respiration rate of cytochrome c oxidase vesicles was increased by ~70% in the presence of $20{\mu}m$ stearic acid and this uncoupling was attributed to a simple protonophoric effect of stearic acid.

• BMB Reports
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• 제29권4호
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• pp.300-307
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• 1996

ATP and ADP are potential regulators of mitochondtial respiration and at physiological concentrations they affect the rate of electron transfer between cytochrome c and cytochrome c oxidase. The electron transfer, however, depends on the electrostatic interaction between the two proteins. In order to exclude any nonspecific ionic effects by these polyvalent nucleotides, we used 2'-O-(2,4,6)trinitro(TNP)-derivatives of ATP and ADP which have three orders of magnitude higher affinity for cytochrome c oxidase. A simple titration of the fluorescence intensity of TNP by cytochrome c oxidase showed a binding stoichiometry of 2:1 cytochrome c:cytochrome c oxidase. Higher ionic strength was required for TNP-ATP than for TNP-ADP to be dissociated from cytochrome c oxidase, indicating that the negative charges on the phosphate group are at least partially responsible for the binding. In both spectrophotometric and polarographic assays, addition of ATP (and ADP to a less extent) showed an enhanced cytochrome c oxidase activity. Both electron paramagnetic resonance and fluorescence spectra indicate that there is no Significant change in the cytochrome c-cytochrome c oxidase interaction. Instead, reduction levels of the cytochromes at steadystate suggest that the increased activity of nucleotide-bound cytochrome c oxidase is due to faster electron transfer from cytochrome ${\alpha}$ to cytochrome ${\alpha}_3$, which is known to be the fate limiting step in the oxygen reduction by cytochrome c oxidase.

• BMB Reports
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• 제33권3호
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• pp.285-288
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• 2000

Ferricytochrome c was artificially made to receive the aqueous electrons evolved through the influence of illuminated chloroplast. This ferricytochrome c, which was bombarded by electrons, was reduced to ferrocytochrome c by making sure that a certain cytochrome is reduced. This may require an electronic attack that is created by the chloroplast inside the plant cell. The possibility of reversing the oxidation of ferrocytochrome c by cytochrome oxidase was examined using a contrived redox system composed of cytochrome oxidase, ferricytochrome c and chloroplast with illumination. We recognized that the oxidase is unserviceable for the reversibleness in spite of the existence of chloroplast.

• Korean Journal of Acupuncture
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• 제36권4호
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• pp.200-209
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• 2019

Objectives : The liver is rich in mitochondria and it plays a key role in whole-body energy homeostasis. Mitochondria is double membrane-bound organelle that supplies energy for intracellular metabolism including Krebs cycle and beta-oxidation. Acupuncture is known to stimulate and regulate the flow of energy. To explore the effect of acupuncture on the mitochondrial respiratory chain activity in the rats' livers, the activity of mitochondrial respiratory chain complexes I to IV was observed. Methods : The rats were divided into 4 groups; Normal 1 (no acupuncture treatment and anesthesia for 5 min), Normal 2 (no acupuncture treatment and anesthesia for 10 min), MA1 (acupuncture treatment at bilateral LR3 under anesthesia for 5 min), and MA2 (acupuncture treatment at bilateral LR3 under anesthesia for 10 min). All rats were sacrificed and the livers were examined for respiratory chain change. Results : There was no difference in ubiquinon oxidoreductase, succinate dehydrogenase, and ubiquinol cytochrome C oxidoreductase after acupuncture at LR3. Acupuncture at LR3 for 10 min increased the activity of cytochrome C oxidase compared with no acupuncture groups. Conclusions : Acupuncture at LR3 mediated mitochondrial respiratory chain activity via the cytochrome C oxidase signaling pathway in the livers of rats.

• Korean Journal of Acupuncture
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• 제37권1호
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• pp.37-45
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• 2020

Objectives : Mitochondria are typically known as intracellular double membrane-bound structures that supply energy for intracellular metabolism including Krebs cycle and beta-oxidation. Also, acupuncture has been known to stimulate the flow of energy. To explore the effect of acupuncture on the mitochondrial respiratory chain activities in rat's heart and kidneys, the activities of mitochondrial respiratory chain complexes I to IV were observed. Methods : The rats were divided into 11 groups; Normal (no acupuncture treatment and under anesthesia for 10 min), heart meridian five-transport-points (acupuncture treatment at HT9, HT8, HT7, HT4 and HT3 under anesthesia for 10 min), and kidney meridian five-transport-points (acupuncture treatment at KI1, KI2, KI3, KI7 and KI10 under anesthesia for 10 min). All rats were sacrificed and the heart and kidneys were examined for the changes of respiratory chain activities. Results : Acupuncture at HT7 increased the activity of succinate dehydrogenase; acupuncture at KI2 increased the activity of ubiquinol cytochrome C oxidoreductase; and acupuncture at HT9, HT8, HT3 and KI1 increased activities of cytochrome C oxidase. Conclusions : Acupuncture assists mitochondrial repiratory chain activity via the Cytochrome C oxidase signaling pathway in heart and kidney of rats.

• Journal of the Korean Wood Science and Technology
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• 제38권2호
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• pp.135-139
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• 2010

Reticulitermes speratus is commonly found in Asia, including Korea and Japan. We recently analyzed the 5' region of mitochondrial cytochrome c oxidase subunit I to perform a phylogenetic analysis of R. speratus KMT1, isolated in Seoul, Korea. Our results, using COXI, suggest that the taxonomy of R. speratus should be reconsidered with regard to the subgenus group. A similar phylogenetic analysis by COXI and COXII demonstrated the reliability of COXI genetic information in a molecular phylogenetic analysis of termites.

• 한국수산과학회지
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• 제29권6호
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• pp.876-881
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• 1996

To determine the amount of genetic variation among populations of Penaeus chinensis (Osbeck) in the Yellow Sea, 342 bp region of the mitochondrial cytochrome c oxidase subunit I gene was amplified and sequenced. Six haplotypes, which differ by from one to four nucleotide sustitutions, were detected from 34 individuals of 4 populations examined. Mean sequence divergence between pairs of haplotypes was $0.68\%$. Most individuals from 4 populations were shared by the most common genotype. This genotype was distributed evenly in the Korean and Chinese populations. This result is in accordance with findings observed using RFLPs analysis of mtDNA (Hwang et al., 1997). Therefore, it is suggested that P. chinensis should be treated as one unit stock in the Yellow Sea.

• Applied Microscopy
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• 제38권2호
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• pp.125-133
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• 2008

Mitochondria 내막의 cytochrome-c-oxidase는 세포의 에너지 생합성에 중요한 요소이며, 세포자멸사와 각종세포의 병리학적 현상과 밀접한 연관성이 있는 전자전달계효소로 알려져 있다. Porin 단백은 mitochondria 내막과 외막에 분포하는 효소단백으로 전자전달계효소 형성과 ATP 운반에 관여하는 것으로 알려져 있다. 따라서 면역현미경법을 사용하여 cytochrome-c-oxidase의 분포와 porin 단백과의 연관성을 확인하여 mitochondria의 cristae에 분포하는 cytochrome-c-oxidase의 형성과 변화를 알아보고자 하였다. Cardiac muscle tissue의 sarcoplasm에는 많은 수의 mitochondria가 분포하며, cytochrome-c-oxidase가 풍부한 mitochondria와 porin 단백이 풍부한 mitochondria로 구별되었다. Cytochrome-c-oxidase가 풍부한 mitochondria는 porin 단백이 빈약하고 porin 단백이 풍부한 mitochondria는 cytochrome-c-oxidase가 소량 포함되어 있는 것으로 관찰되었다. 심근조직의 부위에 따라 근형질에 분포하는 mitochondria에 cytochrome-c-oxidase가 풍부한 mitochondria와 porin 단백이 풍부한 mitochondria가 각각 상이하게 분포하였다. 이상의 결과로 미성숙 mitochondria는 많은 양의 porin 단백을 함유하여 근형질로부터 단백질 소단위를 mitochondria 막내로 운반하여 cytochrome-c-oxidase를 형성시키고 mitochondria가 성숙하면서 ATP를 운반할 최소한 양의 porin 단백만을 남기고 소멸되는 것으로 추측된다.

• Parasites, Hosts and Diseases
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• 제45권3호
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• pp.181-190
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• 2007

The phylogenie relationships existing among 14 parasitic Platyhelminthes in the Republic of Korea were investigated via the use of the partial 28S ribosomal DNA (rDNA) D1 region and the partial mitochondrial cytochrome c oxidase subunit 1 (mCOI) DNA sequences. The nucleotide sequences were analyzed by length, G + C %, nucleotide differences and gaps in order to determine the analyzed phylogenie relationships. The phylogenie patterns of the 28S rDNA D1 and mCOI regions were closely related within the same class and order as analyzed by the PAUP 4.0 program, with the exception of a few species. These findings indicate that the 28S rDNA gene sequence is more highly conserved than are the mCOI gene sequences. The 28S rDNA gene may prove useful in studies of the systematics and population genetic structures of parasitic Platyhelminthes.

• BMB Reports
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• 제28권3호
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• pp.254-260
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• 1995

Cytochrome oxidase was purified from bovine-heart mitochondria and its enzymatic properties were examined. The purified cytochrome oxidase was identified by its absorption spectrum and chromatogram through gel filtration. The specific activity, purification degree and yield of purified cytochrome oxidase were 18 nmol/mg/ml/min, 24.83 fold and 0.93%, respectively. The activity of the enzyme assayed by a ferrocytochrome $c-O_2$ system was optimized at $25^{\circ}C$ and pH 6.5. Examining the effect of nonionic detergents established that cytochrome oxidase was deactivated by Triton X-100. The oxidase was activated by Tween 80 and deactivated by Tween 20. The Michaelis constant and maximum velocity of the oxidase for ferrocytochrome c were 0.032~0.044 mM and 0.019~0.021 mM/min, respectively. After adaption to basal diet for a week, experimental diets containing 6 mg Cu/kg, or zero mg Cu/kg, or 12 mg Cu/kg were fed to a control group, a copper-free group and a copper-rich group of Sprague-Dawley rats, respectively, for 4 weeks. The specific activities assayed for the ferrocytochrome $c-O_2$ system of isolated cytochrome oxidase from the rat liver of control, copper-free, and copper-rich group were 1.00, 1.19, and 0.878 nmol/mg/ml/min, respectively. Their degrees of purification were 11.38, 10.82 and 8.78 fold, respectively. The specific activities for liver and heart mitochondrial cytochrome oxidase of copper-free/copper-rich groups assayed using the ferrocytochrome $c-O_2$ system were 81.4% and 96.4%/64.1% and 61.1%, respectively, compared with those of the control.