Greening 과정에 따른 광인산화 및 몇가지 전자전달물질의 활성 변화

표장근,이인철,이순희,Pyo, Jang-Geun,Lee, In-Cheol,Lee, Sun-Hi 생화학분자생물학회 1986 한국생화학회지 Vol.19 No.4

보리(Hordeum vulgare L. cv. Baecdong) 잎의 greening 과정에서 광인산화능, coupling factor($CF_1$), P700, ferredoxin-$NADP^+$ oxidoreductase, plastocyanin의 변화를 측정하였다. 광인산화능은 greening을 시작한 후 12시간 이후에 급격히 증가하였으며 특히 비순환석 광인산화에 비해 순환적 광안산화에 의한 ATP 생성이 200% 이상 높았다. $CF_1$의 함량은 greening 6시간 이후 9시간까지 급격히 증가하였으나, 그 활성은 점증적인 증가를 나타내고 있었다. P700의 함량에 있어서도 greening과 더불어 증가하였으며 특히 3시간 이후에 현저하였다. Ferredoxin-$NADP^+$ oxidoreductase의 경우에는 greening에 따라 그 활성이 증가하였으나 다른 전자 전달계 관련 물질의 변화 양상과는 달리 12시간 이후에 200% 이상 증가하여 광인산화능의 변화와 유사하였다. 그러나 P700에 전자를 공여하는 plastocyanin은 거의 모든 실험구에서 그 함량이 일정하여 greening에 따른 변화를 나타내지 않는 것으로 나타났다. 이러한 실험 결과들은 광인산화능이나 그 외의 엽록체 내막계에서 전자 전달에 관련된 물질들이 엽록체의 분화와 더불어 합성될 뿐만 아니라, 그 활성도 엽록체의 분화에 의해 영향을 받는다고 사료된다. Attempts were made to describe the changes of activities of photophosphorylation and ferredoxin-$NADP^+$ oxidoreductase, and amounts of P700, coupling factor ($CF_1$) and plastocyanin during chloroplast development in the etiolated barley leaves. Activities of both cyclic and noncyclic photophosphorylation were observed to increase rapidly after 12 h following exposure of etiolated seedlings to light. Activities of cyclic photophosphorylation showed approximately 2 fold increase over the noncyclic photophosphorylation activities. The amounts of $CF_1$ increased markedly to 9 h, however, $CF_1$ activities increased gradually with greening. Among those compounds involved in photosynthetic electron transport, the amounts of P700 increased rapidly after 3 h of greening. But the activities of ferredoxin-$NADP^+$ oxidoreductase were found to increase markedly (above 200%) which pattern was similar with that of photophosphorylation. On the contrary, the amount of plastocyanin, an electron donor to P700, was constant during greening.

Greening 과정에서 따른 광인산화 및 몇가지 전자전달물질의 활성 변화

표장근,이인철,이순희 ( Jang Geun Pyo,In Cheol Lee,Sun Hi Lee ) 생화학분자생물학회 1986 BMB Reports Vol.19 No.4

Attempts were made to describe the changes of activities of photophosphorylation and ferredoxin-NADP+ oxidoreductase, and amounts of P700, coupling factor (CFr) and plastocyanin during chloroplast development in the etiolated barley leaves. Activities of both cyclic and noncyclic photophosphorylation were observed to increase rapidly after 12 h following exposure of etiolated seedlings to light. Activities of cyclic photophosphorylation showed approximately 2 fold increase over the noncyclic photophosphorylation activities. The amounts of CF₁ increased markedly to 9 h, however, CF₁ activities increased gradually with greening. Among those compounds involved in photosynthetic electron transport, the amounts of P700 increased rapidly after 3 h of greening. But the activities of ferredoxin-NADP^+ oxidoreductase were found to increase markedly (above 200%) which pattern was similar with that of photophosphorylation. On the contrary, the amount of plastocyanin, an electron donor to P700, was constant during greening.

Generation of Superoxide Radical from Rat Brain Mitochondria and Mechanism of Its Toxic Action to Mitochondrial and Extra-mitochondrial Components

노재규,표장근,정명희,임정규,명호진,Roh, Jae-Kyu,Pyo, Jang-Geun,Chung, Myung-Hee,Lim, Jung-Kyoo,Myung, Ho-Jin The Korean Society of Pharmacology 1985 대한약리학잡지 Vol.21 No.1

흰쥐 뇌 미토콘드리아에 의한 $O^{-}_{2}{\cdot}$ 의 생성과 이 radical의 유해작용 및 그 작용기전을 알아보기 위하여 본실험을 수행하였다. Succinate와 antimycin존재하에서 미토콘드리아는 $O^{-}_{2}{\cdot}$을 생성하였으며 이는 SOD-inhibitable NBT환원으로 확인되었다. 동일 조건에서 $H_2O_2$는 일차생성물인 $O^{-}_{2}{\cdot}$의 dismutation으로 생성됨을 알수 있었다. 상기조건에서 미토콘드리아의 막지질이 파괴되었고 반응액에 첨가된 isocitrate dehydrogenase와 적혈구에 각각 불활성화와 용혈이 초래되었다. 이같은 작용은 $Fe^{++}$이 있을때만 관찰 되었다. 그리고 독작용은 superoxide dismutase 혹은 castalase에 의해서 억제되었다. 또한 methional을 첨가하였을 때 ethylene이 생성되었으며 그 생성은 $Fe^{++}$에 의하여 현저히 증가하였다. Ethylene 생성 역시 상기 효소에 의하여 억제되었다. 따라서 미토콘드리아에서 발생된 $O^{-}_{2}{\cdot}$은 거대분자 및 세포에 독성을 나타낼수 있으며 이같은 작용은 $Fe^{++}$의 촉매작용에 의한 $O^{-}_{2}{\cdot}$와 $H_2O_2$의 상호작용으로 발생되는 $OH{\cdot}$ 에 의한것으로 추측되었다. 이상의 결과는 미토콘드리아가 유독성 산소 radical을 발생하므로 조직손상을 시킬 수 있다는 가능성을 시사하는 증거라고 생각되었다. 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.

동이온이 촉매작용에 의한 과산화현상에 있어서 Hydroxyl Radical이 관여한다는 실험적 증거 ( Evidence for Hydroxyl Radical Involvement in Cu++ -Catalyzed Peroxidation )

이영석,정명희,표장근,김용식,김명석 한국환경성돌연변이발암원학회 1986 한국환경성돌연변이·발암원학회지 Vol.6 No.2

활성산소에 의한 조직손상에 미치는 인삼성분의 보호효과 ( Protective Effects of a Ginseng Component , Maltol ( 2-Methyl-3-Hydroxy-4-Pyrone ) against Tissue Damages Induced by Oxygen Radicals )

신재국,박종완,표장근,김명석,정명희 고려인삼학회 1990 Journal of Ginseng Research Vol.14 No.2

흰쥐 뇌 미토콘드리아에 의한 superoxide radical의 생성과 이 radical이 미토콘드리아 및 미토콘드리아 외 물질에 대한 독작용과 그 기전에 관한 연구

노재규(Jae-Kyu Roh),표장근(Jang-Geun Pyo),정명희(Myung-Hee Chung),임정규(Jung-Kyoo Lim),명호진(Ho-Jin Myung) 대한약리학회 1985 대한약리학잡지 Vol.21 No.1

흰쥐 뇌 미토콘드리아에 의한 O₂^-⋅ 의 생성과 이 radical의 유해작용 및 그 작용기전을 알아보기 위하여 본실험을 수행하였다. Succinate와 antimycin존재하에서 미토콘드리아는 O₂^-⋅을 생성하였으며 이는 SOD-inhibitable NBT환원으로 확인되었다. 동일 조건에서 H₂O₂는 일차생성물인 O₂^-⋅의 dismutation으로 생성됨을 알수 있었다. 상기조건에서 미토콘드리아의 막지질이 파괴되었고 반응액에 첨가된 isocitrate dehydrogenase와 적혈구에 각각 불활성화와 용혈이 초래되었다. 이같은 작용은 Fe⁺⁺이 있을때만 관찰 되었다. 그리고 독작용은 superoxide dismutase 혹은 castalase에 의해서 억제되었다. 또한 methional을 첨가하였을 때 ethylene이 생성되었으며 그 생성은 Fe⁺⁺에 의하여 현저히 증가하였다. Ethylene 생성 역시 상기 효소에 의하여 억제되었다. 따라서 미토콘드리아에서 발생된 O₂^-⋅은 거대분자 및 세포에 독성을 나타낼수 있으며 이같은 작용은 Fe⁺⁺의 촉매작용에 의한 O₂^-⋅와 H₂O₂의 상호작용으로 발생되는 OH⋅ 에 의한것으로 추측되었다. 이상의 결과는 미토콘드리아가 유독성 산소 radical을 발생하므로 조직손상을 시킬 수 있다는 가능성을 시사하는 증거라고 생각되었다. The generation of O₂^-⋅ and its toxic effects were studied with rat brain mitochondria. The production of O₂^-⋅ from mitochondria in the presence of succinate and antimycin was demonstrated by SOD-inhibitable reduction of NBT. Although succinate can support the O₂^-⋅ 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, H₂O₂ was also observed to be produced. But its formation appears to be derived from the dismutation of the primary product, O₂^-⋅ since the rate of H₂O₂ production was markedly decreased by NBT and ferricytochrome c. The O₂^-⋅ and H₂O₂ 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⋅ 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 O₂^-⋅ may provide evidence supporting a potential role of mitochondria as a source of oxygen radicals to cause tissue damage.