• Biotechnology and Bioprocess Engineering:BBE
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• 제8권2호
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• pp.94-100
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• 2003

We studied the effect of cadmium on chlorophylls and rubisco activation in Canavalia ensiformis L. leaves. Chlorophyll levels were reduced by 5.0 ${\mu}$M Cd. Rubisco activity at 5.0 ${\mu}$M Cd was significantly smaller than that at no treatment. Rubisco Content showed patterns of change similar to rubisco activity. These data suggest that rubisco activity was associated with an amount of rubisco protein, and that the activation and induction of rubisco is inhibited by Cd. The degree of intensity of 50 and 14.5 kD polypeptides identified as the large and small subunit of rubisco by SDS-PAGE analysis at 5.0 ${\mu}$M Cd was significantly lower than that at control, indicating Cd had a e f-fect on both subunits. Under the assumption that effects of Cd on rubisco may be r elated to rubisco activase, in addition to, its activity and content we re determined . The rubisco activase activity at 5.0 ${\mu}$M Cd was more decreased than the control. A similar change pattern was also observed in content of rubisco activase. Remarkable differences in the intensitiy of both the 45 kD and 41 kD band were found between at control and Cd-treatment. These results suggest that the change in the levels of rubisco activase leads to a subsequent alter action of rubisco levels.

• Journal of Photoscience
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• 제9권2호
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• pp.385-387
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• 2002

Direct EPR evidence of the photo-generation of superoxide radicals ( $O_2$$^{-.}$) was obtained by using spin trapping techniques in spinach photosystem II (PSII) membranes. $O_2$$^{-.}$ was detected by following the formation of 5-diethoxyphosphoryl-5-methyl-1 -pyrroline-N-oxide (DEPMPO) superoxide adducts, DEPMPO-OOH. The significant increase of the EPR signal amplitude of DEPMPO-OOH in N$H_2O$H-, CaC $l_2$- and NaCl-treated PSII membranes showed that the oxygen-evolving system has a close relation to the $O_2$$^{-.}$ production. PSII membranes with inactivated donor side could not prevent the $O_2$$^{-.}$ production efficiently. Treatments on PSII donor side also influence the maximum level and the kinetics of Chlorophyll (Chi) a fluorescence. Results suggested that manganese cluster and extrinsic proteins might affect Chi a fluorescence in ways different from that happens at the acceptor side of PSII.SII.SII.

• Plant Resources
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• 제2권2호
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• pp.127-132
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• 1999

This study was carried out to investigate the morphological characteristics of the plants and seeds of Ainsliaea acerifolia and to determine the optimum condition for producing sprouts from the seeds. Plant height, flower stalk length, and pod number were higher in natural habitat than in campus farm. Average 1.2 seeds per pod was set but only 0 to 2 seeds per plant was set in plants with the enveloped flower stalks, indicating that this is an outcrossing species. Most of seeds were 9-11mm long and 1.1-1.4mm wide. Fresh weight of seeds was ranged from 10mg to 17mg. Seeds germinated well at 15$^{\circ}C$ and 2$0^{\circ}C$. Mean germination period was 11.5 day at 15 to $25^{\circ}C$. Sprouts grown at 15$^{\circ}C$ was longest(5.4cm) and heaviest(738mg/10 sprouts). Chlorophyll content was 333mg per fresh weight 110g. Protein, Fe, vitamin Bl, vitamin B2, and vitamin C were respectively 23.7mg, 6.4mg, 1.82mg, 0.49mg, and 10..7mg.

• 한국연초학회지
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• 제19권2호
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• pp.77-82
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• 1997

In order to investigate biochemical activities of harvested tobacco leaves, photosynthetic rate, soluble protein contents, and peroxidale activities were analysed during different maturing period. Physiological activities of harvested leaves during maturing period were higher in topped than those of non-topped plants. Chlorophyll content and photosynthetic rate in both topped and non-topped plants decreased at 4 days and 3 days before harvest, respectively. The chloroplast numbers in topped and non-topped plants decreased at 3 days and 5 days before harvest, respectively. Changes of soluble protein and total RNA contents showed similar patterns during maturing period. Soluble protein contents were slightly decreased from 5 days before harvest in topped plants, but decreased drastically from 3 days before harvest in non-topped plants. Not much changes were found in total RNA contents in topped plants until 2 days before harvest, and it was largely decreased after 5 days before harvest in non-topped plants. The peroxidase activities drastically decreased in topped plants and increased in non-topped plants after 3 days before harvest during maturing period. The largest change of biochemical activities in tobacco leaves during maturing periods were observed at 3 days before harvest.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.189-189
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• 2022

Soil salinity negatively affects plant growth, productivity, and metabolism. Rice is known to have more sensitive phenotypes than other cereal crops, such as wheat, sorghum, and barley. We characterized the molecular function of rice C3HC4 as a really interesting new gene (RING). Oryza sativa RING finger protein H2-3 (OsRFPH2-3) was highly expressed in 100 mM NaCl. To identify the localization of OsRFPH2-3, we fused vectors that include C-terminal GFP protein (35S;;OsRFPH2-3-GFP). OsRFPH2-3 was expressed in the nucleus in rice protoplasts. An in vitro ubiquitin assay demonstrated that OsRFPH2-3 possessed E3-ubiquitin ligase activity. However, the mutated OsRFPH2-3 were not possessed any E3-ubiquitin ligase activity. Under normal conditions, there is no significant phenotypic difference between transgenic plants and WT plants. However, OsRFPH2-3-overexpressing plants exhibited higher fresh weight and length under saline conditions. Also, transgenic plants maintain higher chlorophyll, proline, and soluble sugar contents and lower H₂O₂ and MDA contents than the wild type; these results support transgenic plants with enhanced salinity tolerance phenotypes.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2023년도 춘계학술대회
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• pp.156-156
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• 2023

Salinity is a major abiotic stress that limits rice productivity in many regions of the world. In order to develop salt stress tolerant rice plants, genetic engineering is a promising approach. We characterized the molecular function of rice C3H2C3 as a really interesting new gene (RING). Oryza sativa RING finger protein H2-3 (OsRFPH2-3) was highly expressed in 100 mM NaCl. To identify the localization of OsRFPH2-3, we fused vectors that include C-terminal GFP protein (35S;;OsRFPH2-3-GFP). OsRFPH2-3 was expressed in the nucleus in rice protoplasts. An in vitro ubiquitin assay demonstrated that OsRFPH2-3 possessed E3-ubiquitin ligase activity. However, the mutated OsRFPH2-3 were not possessed any E3-ubiquitin ligase activity. Under salinity conditions, OsRFPH2-3-overexpressing plants exhibited higher chlorophyll, proline, SOD, POD, CAT, and soluble sugar contents and lower H₂O₂ accumulation than wild-type plants, supporting transgenic plants with enhanced salinity tolerance phenotypes. OsRFPH2-3-overexpressing plants exhibited low Na+ accumulation and Na+/K+ ratios in their roots. Theses results suggest that overexpression of OsRFPH2-3 can make plant insensitivity about salinity conditions.

• 한국작물학회지
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• 제40권2호
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• pp.133-141
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• 1995

약용 식물의 추출액이 자가영양배양세포의 광합성전자전달계에 미치는 영향을 조사하기 위해 9종의 약용식물 추출액으로부터 종자발아, PA세포의 엽록소 억제정도, DCIP의 환원율, 세포 생존율, 광계 I의 전자전달활성, 단백질에 미치는 영향을 조사한 결과는 다음과 같다. 1. 식물의 추출액을 농도별로 처리하였을 때 10％ 처리시 전 식물체에서 상추의 발아억제 현상을 나타내었고, 특히 백두옹과 초오 추출물 10％ 처리시는 100％ 억제를 나타내었다. 2. 백두옹의 증류수 및 MeOH 추출액을 PA세포에 처리한 경우 엽록소의 생성을 100％ 억제 하 였다. 이는 광합성 전자전달 저해제로 알려진 DCMU 10-3M 처리와 동일한 억제 효과였다. 3. PA세포에 추출물 처리시 백두옹이 힐반응 억제가 가장 컸으며, 세포 생존력은 가장 낮았다. 4. 광합성 산소발생은 반하, 독활, 백두옹, 만형자 추출액 처리시 14-77％ 억제되었고, 특히 PA 세포 2ml 반응액에 백두옹 추출물 60rl 처리시 50％ 산소발생 억제를 나타내었다. 5. 추출액을 PA 세포에 처리한 후 단백질을 추출하여 SDS-PAGE를 이용하여 조사한 결과 대조구에 비하여 백두옹 추출물 10％ 처리에서 14KD, 31KD, 41KD, 53KD, 73KD의 밴드가 나타나지 않았다.

• 생물환경조절학회지
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• 제17권4호
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• pp.273-282
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• 2008

수분 공급을 제한하여 수분 부족 스트레스를 처리한 상추식물에서 산화적 스트레스와 관련된 monodehydroascorbate reductase (MDHAR)의 활성도, 엽록소 함량, 과산화수소의 함량 등과의 상관관계를 조사한 결과, 생육배지의 수분의 함량이 감소함에 따라 식물체내 과산화수소의 생성량이 증가($R^2$=0.8851)하였으며, 수용성단백질 함량은 점차 감소($R^2$=0.9826)하는 경향을 나타내었다. 총 엽록소함량은 수분 부족 스트레스를 처리한 공시작물에서의 함량이 정상 생육시 보다 그 함량이 대체적으로 낮은 경향을 보였으며, 엽록소 a와 엽록소 b함량 변화도 총 엽록소의 함량변화와 비슷한 경향을 보였다. 그러나 총 엽록소에 대한 카로티노이드의 비율은 수분 부족 스트레스를 처리한 식물에서 정상생육 시 보다 더 높은 경향을 보였다. 수분 부족 스트레스가 진행됨에 따라 아스코브산의 함량은 정상 생육 시 보다 더 높은 경향을 보였으나 환원형인 디하이드로아스코브산의 함량은 수분 부족 스트레스를 처리한 초기에 정상생육 시 보다 더 낮은 경향을 보였다. MDHAR의 활성도는 사이토졸(cytosolic) 분획과 엽록체(chloroplastic) 분획에서 공히 크게 증가하였으며 MDHAR의 mRNA 전사 정도도 수분 부족 스트레스가 진행됨에 따라 크게 증가하였다. 수분함량이 감소함에 따라 MDHAR의 활성도가 크게 증가하였으며, 또한 과산화수소의 함량이 증가함에 따라서도 MDHAR의 활성도가 크게 증가($R^2$=0.9937과 0.8645)되어 수분 부족 스트레스로 나타나는 요인들과 MDHAR 사이에 밀접한 관련이 있음을 확인할 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제31권6호
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• pp.1479-1484
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• 2010

Photosynthesis uses light energy to drive the oxidation of water at an oxygen-evolving catalytic site within photosystem II (PSII). Chlorophyll binding by the photosystem II subunit S protein, PsbS, was found to be necessary for energy-dependent quenching (qE), the major energy-dependent component of non-photochemical quenching (NPQ) in Arabidopsis thaliana. It is proposed that PsbS acts as a trigger of the conformational change that leads to the establishment of nonphotochemical quenching. However, the exact structure and function of PsbS in PSII are still unknown. Here, we clone and express the recombinant PsbS gene from Arabidopsis thaliana in E. coli and purify the resulting homogeneous protein. We used various biochemical and biophysical techniques to elucidate PsbS structure and function, including circular dichroism (CD), fluorescence, and DSC. The protein shows optimal stability at $4^{\circ}C$ and pH 7.5. The CD spectra of PsbS show that the conformational changes of the protein were strongly dependent on pH conditions. The CD curve for PsbS at pH 10.5 curve had the deepest negative peak and the peak of PsbS at pH 4.5 was the least negative. The fluorescence emission spectrum of the purified PsbS protein was also measured, and the ${\lambda}_{max}$ was found to be at 328 nm. PsbS revealed some structural changes under varying temperature and oxygen gas condition.

• 한국식품영양과학회지
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• 제11권4호
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• pp.7-12
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• 1982

콩나물 재배시(栽培時)에 $25^{\circ}C$에서 blue광(光)을 120Lux로 1일(日) 1회(回) 3시간(時間) 조사(照射)하면서 생장상태(生長狀態), chlorophyll, vitamin C, 단백질함량(蛋白質含量), 단백질(蛋白質)의 pattern 및 trypsin inhibitor activity의 변화(變化)를 암소(暗所)와 상호비교(相互比較)하였다. 콩나물 배축부(胚軸部)의 길이는 blue광(光)에서 다소(多少) 길었으나 함량(重量)에는 차이(差異)가 인정(認定)되지 않았다. Blue광하(光下)에서의 chlorophyll함량(含量)은 3일(日)에 3.57g/100g-f. w., 7일(日)에 8.45g/100g-f. w.로서 재배일정(栽培日數)의 경과에 따라 현저히 증가(增加)하였다. vitamin C의 함량(含量)은 blue광(光) 조사(照射)에 의(依)하여 현저히 증가(增加)되었으며, 재배(栽培) 5일(日)의 자엽부(子葉部)는 21.7% 배축부(胚軸部)는 30.8%가 암소(暗所)에 비(比)하여 높았다. TIA는 blue광(光)에 의(依)한 영향(影響)이 거의 없었으며, 재배(栽培) 5일(日)의 자엽부(子葉部)는 원료대두(原料大豆)와 거의 비슷하였고, 배축부(胚軸部)는 매우 낮아 자엽부(子葉部)의 약(約) 23%에 불과하였다. 단백질(蛋白質)의 함량(含量) 변화(變化)는 blue광(光)의 효과(效果)를 인정(認定)할 수 없었으며, disc electrophoresis를 행(行)한 결과(結果) 원료대두(原料大豆)에서 10개(個), 자엽부(子葉部)에서 9개(個), 배축부(胚軸部)에서 11개(個)의 단백(蛋白)을 분리(分離) 확인(確認)할 수 있었으며 특(特)히 원료대두(原料大豆)와 자엽부(子葉部)에서 존재(存在)가 확인(確認)되지 않은 band No.3이 배축부(胚軸部)의 주요(主要) 구성단백(構成蛋白)임을 알 수 있었다. 그리고 자엽부(子葉部)에서는 blue광(光)의 영향(影響)이 없었으나 배축부(胚軸部)에서는 band No.5와 11이 blue광(光) 조사시(照射時)에서 존재(存在)가 확인(確認)되었다.