• The Journal of Natural Sciences
• /
• v.5 no.2
• /
• pp.3-11
• /
• 1992

As concentration of ADP was increased, the rate of phosphocreatine formation by respiring heart mitochondria was increased. The value of apparent Km of the phosphocreatine-forming mitochondria for ADP was estimated to be 0.0185 mM. This value was much lower than that of Km for ATP (0.31 mM) which was determined from the reaction of the soluble form of mitochondrial creatine kinase. The concentration of ATP remained constant during the respiring in the presence of ADP. The rate of accumulation of oxidative-phosphorylated ATP in the mitochondrial respiration medium was continuously monitored as a function of ADP concentration with the firefly luciferase-coupled assay. In that case, exogenous creatine did not affect the rate of accumulation of ATP, indicating that phosphocreatine-forming (i.e.,respiring) mitochondria in the presence of ADP did not use the ATP in the medium as a substrate.These results suggest that the heart mitochondrial creatine kinase bound to the inner membrane functionally tight-coupled to the oxidative phosphorylating system with respect to the respired ATP.

• The Korean Journal of Mycology
• /
• v.22 no.2
• /
• pp.117-121
• /
• 1994

Five strains of Pleurotus sajor-caju were collected from some countries including India and Papua New Guinea. Four strains produced brown fruitbody but the other strain from Papua New Guinea produced white fruitbody. Monokaryons obtained from both strains producing brown fruitbody and white fruitbody were mated each other. They showed different mating types such as brown strain of $A_1A_2B_1B_2$ and white strain of $A_3A_4B_3B_4$. DNAs were isolated from mycelia of five strains of P. sajor-caju. Mitochondrial DNA was seperated from nuclear DNA by bisbenzimide-CsCl ultracentrifugation. Digestion of the fungal mitochondrial DNA with Eco RI restriction endonuclease yielded from ten to fourteen fragments. Two strains of the five strains showed different restriction pattern of mitochondrial DNA from the other three strains. Summation of the fragment sizes gave a mitochondrial DNA size of about 60 to 65kb.

• Korean journal of applied entomology
• /
• v.62 no.2
• /
• pp.83-87
• /
• 2023

Nysius plebeius is a major lygaeid pest of various cereal crops and ornamental plants in East Asian countries, including Korea. The complete mitochondrial genome of N. plebeius was characterized and found to comprise a total of 17,367 bp, which included 13 protein-coding genes, NADH dehydrogenase components (complex I, ND), cytochrome oxidase subunits (complex VI, COX), cytochrome oxidase b (CYPB), two ATP synthases, two ribosomal RNA genes, and 22 transfer RNAs. The GC content of 23%. It showed high sequence similarity to other Lygaeidae species, such as N. cymoides (94.5%), N. fuscovittatus (91.7%), and an unknown Nysius species (94.1%). This new N. plebeius mitochondrial genome can be widely used for evolutionary studies of Lygaeidae and to improve pest management practices.

• Journal of the Korean Child Neurology Society
• /
• v.26 no.4
• /
• pp.197-204
• /
• 2018

Purpose: West syndrome is a severe form of age-specific epilepsy that typically affects infants younger than 2 years of age with mitochondrial disease. We aimed to examine age-specific characteristics of the syndrome in these patients. Methods: We retrospectively analyzed 54 patients with West syndrome diagnosed with mitochondrial disease between March 2006 and March 2016. We compared treatment strategies and diagnostic and clinical variables between patients with early-onset (<6 months of age) and late-onset (${\geq}6$ months of age) seizures. Results: Seizure was the first symptom in 30 (90.9%) and 13 (65%) patients of the early-onset and late-onset groups, respectively (P=0.046). Delayed development was observed in 3 (9.1%) and 7 (35%) patients of the early-onset and late-onset groups, respectively (P=0.023). Lactate levels were normal in 17 patients (55%) of the early-onset group and 5 (25%) of the late-onset group (P=0.036), while initial brain magnetic resonance imaging (MRI) findings were normal in 23 (67.6%) and 8 (40%) patients of the early-onset and late-onset groups, respectively. Final MRI findings were abnormal in 32 patients (94.1%) of the early-onset group and 18 (90%) of the late-onset group (P=0.036). Although ketogenic diets reduced seizure frequency in both groups, the difference was not significant. Conclusion: There is no significant difference in epilepsy-related variables when patients are divided based on a cut-off age of 6 months. However, differences in the first symptom at onset and MRI findings were observed. Although lactate levels were not of significant diagnostic value in the early-onset group, they may be in the late-onset group.

• Development and Reproduction
• /
• v.3 no.1
• /
• pp.15-19
• /
• 1999

Preeclampsia is a common, pregnancy-induced hypertensive disease leading to severe morbidity in the mother and fetus. Although the etiology of preeclampsia remains unclear, many studies focus mutation of placental mitochondria as the cause of this disease. This review covers mutation of placental mitochondria as the possible etiology of preeclampsia, prevention and treatment strategies based on the hypothesis of mutation of placental mitochondria in the etiology of preeclampsia.

• Journal of Life Science
• /
• v.16 no.3 s.76
• /
• pp.365-368
• /
• 2006

Yeast mitochondrial transformation has been confirmed by cell death and CFP expression (CDF: cell death factor gene). Expression vector containing CDF and CFP driven by one TPI (Triose-phosphate isomerase) promoter (called artificial operon type) was bombarded to Yeast. Interestingly, yeast cells were progressively deformed into unusual shapes and lysed inner cytoplasm resulting in ell death after all after bombarding with expression vector (CDC and GFP). Since there is no report about more than one gene expression simultaneously in a single mitochondria, this report is very important to novel type of eukaryotic gene expression. Successful yeast cell transformation in this report implies possible eukaryotic mitochodrial transformation including plants and animals and moreover two or more gene expression which can be excellent applicable protocols to pharmaceutical field including antibody production.

• The Korean Journal of Zoology
• /
• v.13 no.3
• /
• pp.85-93
• /
• 1970

Measurements were made of the $Ca^++$ uptake, oxygen consumption and ATPase activity of mitochondria extracted from the rat liver in sucrose-tris chloride medium. $Ca^++$ binding of mitochondria was not affected by the incubation temperature in the range of $0^\\circ - 37^\\circ C$. Succinate did not increase the amount of $Ca^++$ bound while it increased oxygen consumption highly. The presence of ATP in the incubation medium did not enhance the $Ca^++$ uptake either. Therefore, it is concluded that the initial binding of $Ca^++$ is independent on metabolism.

• Journal of the Korean Chemical Society
• /
• v.44 no.5
• /
• pp.448-452
• /
• 2000

Phospholipase D(PLD) is the enzyme catalyzing the hydrolysis of the terminal phosphcester bond of phospholipid head group to produce phosphatidic acid and the corresponding base. The effect of spermine on the PLD activity of rat brain mitochondrial preparation was investigated. Spermine, in the presence of oleic acid, activates the rat brain mitochondrial PLD, whose effect was further enhanced by the presence of divalent cation, $Ca^{2+}$, $Mg^{2+}$, and $Ba^{2+}$. Among the various monoamines tested, only histamine at the high concentration was effective in activation the PLD. Polylysine increased the PLD activity, particularly, the longer chain of the molecule activated the PLD more effectively. There was no significant difference in the substrate specificity for the PLD activity between phosphatidylcholine(PC) and phoshpatidylethanolamine (PE). This substrate specifitiy is different from the PE specificity reported for the intestinal mitochondrial PLD.

• Korean Journal of Ichthyology
• /
• v.34 no.1
• /
• pp.1-7
• /
• 2022

A larva of the deep-sea angler fish, Himantolophus groenlandicus (2.2 mm BL), identified based on the complete mitochondrial DNA sequence, was collected at the surface of the western North Pacific. The postflexion stage larva had a round body, small teeth, incipient dorsal fin rays, eyes slightly recessed in the lower part, and melanophores on the gills and parietal and dorsal regions. These morphological features differ from a description of a larva reported as the same species with similar size (2.1 mm BL). The genetic and morphological information of our specimen should be useful for identifying larval H. groenlandicus.

• The Korean Journal of Pharmacology
• /
• v.21 no.1
• /
• pp.12-26
• /
• 1985

The generation of $O^{-}_{2}{\cdot}$ and its toxic effects were studied with rat brain mitochondria. The production of $O^{-}_{2}{\cdot}$ from mitochondria in the presence of succinate and antimycin was demonstrated by SOD-inhibitable reduction of NBT. Although succinate can support the $O^{-}_{2}{\cdot}$ formation, the highest rate needs antimycin indicating that blockade of electron flow in the respiratory chain augments the univalent reduction of molecular oxygen. Under this condition, $H_2O_2$ was also observed to be produced. But its formation appears to be derived from the dismutation of the primary product, $O^{-}_{2}{\cdot}$ since the rate of $H_2O_2$ production was markedly decreased by NBT and ferricytochrome c. The $O^{-}_{2}{\cdot}$ and $H_2O_2$ produced were able to cause toxic actions to mitochondrial and extra-mitochondrial components as shown by lipid peroxidation of mitochondrial membrane, and inactivation and lysis of isocitrate dehydrogenase and erythrocytes added to the medium, respectively. In all the toxic actions observed, $Fe^{++}$ was required. It appears that in the toxic actions $OH{\cdot}$ generated from the iron-catalyzed Haber-Weiss reaction acts as a mediator. This was supported by the finding that mitochondria in the presence of succinate and antimycin produced ethylene from methional, and $Fe^{++}$ added increased the ethylene production. The observed toxic actions of mitochondrial $O^{-}_{2}{\cdot}$ may provide evidence supporting a potential role of mitochondria as a source of oxygen radicals to cause tissue damage.