• The Korean Journal of Mycology
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• v.17 no.4
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• pp.177-183
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• 1989

Mitochondria in Pleurotus ostreatus was purified by stepped sucrose density gradient centrifugation. The mitochondrial ATP synthase was investigated by various waveof the illumination at dark room for 30 min. The mitochondrial ATP synthase activity was stimulated 2.3 fold by 480 nm illumination compared with the broad wavelength group. The mitochondrial ATP synthase activity according to various times of illumination was stimulated 4.2 fold for 15 min at 480 nm compared with the broad wavelength group. The optimum pH and optimum temperature of the mitochondrial ATP synthase were 7.5 and $56^{\circ}C$, respectively. The activity of this enzyme was stimulated by 0.5 mmol $Fe^{2+}$, 1.0 mmol $Fe^{3+}$ and 5.0 mmol $k^+$ ion, but inhibited by 0.1 mmol $Na^+$ ion.

• The Korean Journal of Mycology
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• v.17 no.2
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• pp.99-104
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• 1989

Effects of organic compounds, photosensitizers and influx of metal ions on the light-induced mitochondrial ATP synthase in Lentinus edodes purified by stepped sucrose density gradient centrifugation were studied. In our previous work, the activation wavelength and the illumination time of mitochondrial ATP synthase were 470 nm and 15 sec, respectively. This enzyme was activated 85% by 1 mmole 2,6-dichlorophenol indopheol and inhibited by 1 mmole 2,-4-dinitrophenol, $10\;{\mu}mole$ 2-heptyl-4-hydroxyquinoline-N-oxide and $100\;{\mu}g$ oligomycin per ml of ethanol. Particularly, the enzyme was activated 414% by 10 mmole phenazine methosulfate as photosensitizer at 470 nm light. In the influx effects of $Fe^{3+}$ and $Fe^{2+}$ ion, the activity of the above enzyme increased under the optimal light condition compared with nonillumination state.

• The Korean Journal of Mycology
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• v.19 no.1
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• pp.32-40
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• 1991

Mitochondria in Pleurotus ostreatus were isolated and purified by the stepped sucrose density gradient centrifugation, to investigate the effects of the light on the enzymatic activity of the mitochondrial ATP synthase. This enzyme, which was illuminated by the light ranging from 400 nm to 700 nm, showed that the specific activity was stimulated at 490 nm for 15 sec. Effects of organic compounds on the mitochondrial ATP synthase were also investigated at the optimum conditions; The activities of this enzyme were increased to 168 percent by the addition of 2,6-dichlo­rophenol indophenol(DCPIP), 224 percent by phenazine methosulfate(PMS), but inhibited 91 per­cent by oligomycin, 14 percent by 2-heptyl-4-hydroxyquinoline-N-oxide(HQNO) and 75 percent by 2,4-dinitrophenol (DNP), respectively. Effects of metal ions of the mitochondrial ATP synthase were investigated at the optimum conditions. The activities of the enzyme were inhibited 35 percent by $Ca^{2+}$, 14 percent by $Co^{2+}$ and 73 percent by $Mn^{2+}$. For effects of anions, the activities of this enzyme were inhibited 80 percent by $CN^{-}$, 52 percent by $SO_{4}\;^{2-}$, 28 percent by each of $CO_{3}\;^{2-}$­and $NO_{3}\;^{-}$, respectively.

• The Korean Journal of Mycology
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• v.17 no.3
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• pp.161-168
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• 1989

Mitochondria in L. edodes were separated and purified by stepped sucrose density gradient centrifugation. In our previous work, we have found that the activation wavelengths of the mitochondrial ATPase and ATP synthase were 680 nm and 470 nm within the range of 400-700 nm, respectively. The activities of the above enzymes with wavelengths of 300-400 nm region were investigated. The mitochondrial ATPase and ATP synthase were stimulated at 380 nm and 330 nm, respectively, for 30 min illumination compared with dark control group. They, however, were inhibited at 330 nm and 350 nm, respectively. The presence of FAD resulted in inhibition of the activity of the ATPase and stimulation of the activity of the ATP synthase by the activation and inhibition wavelengths. However, the activities of these enzymes were not changed by NADH for the above wavelengths. In the spectral properties, the oxidation of $FADH_2$ into FAD occurs in the presence of the enzymes for illumination of the activation and inhibition wavelengths. Therefore, we can predict that the mitochondrial ATPase and ATP synthase may function as oxidant in the redox reaction by the light illumination and that the light-induced pigment of the mitochondrial ATP synthase should be an oxidized form of a flavoprotein.

• The Korean Journal of Mycology
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• v.17 no.2
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• pp.91-98
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• 1989

Mitochondria in the L. edodes was separated and purified by stepped sucrose density gradient centrifugation. The activity of mitochondrial ATP synthase has been investigated during various illumination times at each wavelength within the range of 400 nm to 700 nm. The stimulation of above activity increased by two times compared with nonilluminated control group when the illumination was given for 15 seconds at 470 nm wavelength. The optimal pH and temperature of this light-induced mitochondrial ATP synthase were 7.5 and $54^{\circ}C$, respectively. The activity of this enzyme increased by 26%, 25% and 14%, respectively, when there were 1 mmole $Fe^{3+}$, 0.5 mmole $Fe^{2+}$, and 5 mmole ${SO_4}^{2-}$ ion, and was inhibited by 5 mmole $Co^{2+}$, 5 mmole $Mn^{2+}$, 1 mmole $Ca^{2+}$, 0.1 mmole $Na^+$, 5 mmole $CN^-$, and 0.1 mmole ${CO_3}^{2-}$ ion. But $Na^+$ and $K^+$ ion did not affect the activity of enzyme.

• The Korean Journal of Mycology
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• v.21 no.3
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• pp.165-171
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• 1993

The effects of the iron ions for the light-induced mitochondrial $F_0F_1-ATPase$ of Lentinus edodes was studied. The enzyme activity was stimulated up to 202% by 0.1 mM $Fe^{2-}$ ion, but was inhibited by $Fe^{3+}\;and\;Mg^{2+}$. In the presence of 0.5 mM $Mg^{2+}$, the activity also increased 32% by 0.1 mM $Fe^{2+}$ ion, and decreased to a similar extent by $Fe^{3+}$ ion than by only $Fe^{3+}$ ion. Also, the activity was inhibited 53% by 5.0 mM $Fe^{2-}$ ion in the presence of 0.5 mM $Mg^{2+}$ ion and various concentration of $Fe^{3+}$ ion(mM). These results showed that $Fe^{2+}$ strongly stimulated the enzyme activity and its role for the enzyme was independent of $Mg^{2+}$ ion, but was dependent of $Fe^{3+}$ ion. From inactivation of the enzyme by addition of metal chelating agent, EDTA, it is suggested that the enzyme is to be metalloenzyme. The optimal pH and temperature of the enzyme in the presence of 0.1 mM $Fe^{2+}$ was 7.6 and $63^{\circ}C$, respectively.

• The Plant Pathology Journal
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• v.30 no.1
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• pp.58-67
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• 2014

The multifunctional triple gene block protein 1 (TGB1) of the Potexvirus Alternanthera mosaic virus (AltMV) has been reported to have silencing suppressor, cell-to-cell movement, and helicase functions. Yeast two hybrid screening using an Arabidopsis thaliana cDNA library with TGB1 as bait, and co-purification with TGB1 inclusion bodies identified several host proteins which interact with AltMV TGB1. Host protein interactions with TGB1 were confirmed by biomolecular fluorescence complementation, which showed positive TGB1 interaction with mitochondrial ATP synthase delta' chain subunit (ATP synthase delta'), light harvesting chlorophyll-protein complex I subunit A4 (LHCA4), chlorophyll a/b binding protein 1 (LHB1B2), chloroplast-localized IscA-like protein (ATCPISCA), and chloroplast ${\beta}$-ATPase. However, chloroplast ${\beta}$-ATPase interacts only with $TGB1_{L88}$, and not with weak silencing suppressor $TGB1_{L88}$. This selective interaction indicates that chloroplast ${\beta}$-ATPase is not required for AltMV movement and replication; however, TRV silencing of chloroplast ${\beta}$-ATPase in Nicotiana benthamiana induced severe tissue necrosis when plants were infected by AltMV $TGB1_{L88}$ but not AltMV $TGB1_{L88}$, suggesting that ${\beta}$-ATPase selectively responded to $TGB1_{L88}$ to induce defense responses.