• BMB Reports
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• 제30권3호
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• pp.173-176
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• 1997

We isolated a cDNA clone that encodes a ribulose-1,5-bisphosphate carboxylase small subunit (rbcS) from spinach using a soybean rbcS cDNA as a probe. The small subunit consists of 180 amino acids including a transit peptide of 57 residues. Comparison of the amino acid sequence with those of other plant species shows a maximum of 70-80% identical residues. Southern blot analysis suggests the existence of multiple rbcS genes in the spinach genome. Northern blot analysis indicates that the rbcS gene is expressed predominantly in leaves and that the expression of the gene is induced by light.

• BMB Reports
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• 제28권3호
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• pp.271-274
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• 1995

Glycolate oxidase is one of the key enzymes in the pathway of photorespiration. In this study we investigated the effects of light on the expression of the spinach glycolate oxidase gene. Continuous exposure to white light resulted in a gradual increase in the steady-state level of glycolate oxidase mRNA within a time period of 2~24 h in both etiolated and dark-adapted green seedlings. A short white light pulse also increased the level of glycolate oxidase mRNA in etiolated seedlings. The mRNA level reached a maximum at 6~8 h after the pulse and decreased by 24 h after the pulse. The induction patterns of the glycolate oxidase gene by white light appeared similar to those of the rbcS gene, indicating that a common or coordinating regulatory system may be involved in the expression of the glycolate oxidase and rbcS genes. A red light pulse induced an increase in the amount of glycolate oxidase mRNA and this effect was reversed by a subsequent far-red light pulse, suggesting that the expression of the glycolate oxidase gene is regulated by phytochrome.

• The Korean Journal of Ecology
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• 제19권1호
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• pp.21-29
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• 1996

Variation in triacylglycerols(TGs) and fatty acids in Fucus serratus was analyzed for a period of one year. TGs were more concentrated during the summer(2.8mg/g dw)and autumn(2.6mg/g dw) than during the spring (0,7mg/g dw)and winter (0.5mg/g dw). The dominant fatty acides in total liqid were palmitic acid ($C_{16:0}$, 24.1%), oleic acid (($C_{18:1}$, 22.4%) and arachidonic acid (($C_{20:4}$, 14.4%) but the dominant ones in TG were $C_{16:0}$(22.8%), $C_{18:1}$(36.4%) and $C_{18:2}$(linoleic acid, 16.4%). The levels of $C_16$ fatty acids were high in winter while $C_18$ in summer and autumn. The polyunsaturated fatty acids (UFAs) were more abundant in the $C_20$ series, while the UFAs of the $C_16$ were low. Especially, the amount of arachidonic acid ($C_{20:4}$, 14.4% of total fatty acids (TFA) was more abundant than that of eicosapentaenoic acid ($C_{20:5}$, 10.4% of TFA). The amount of $C_{20:4}$ and $C_{20:5}$,in TG was 9.2% and 4.8%, respectively. These UFAs in total lipid were thus higher than TG. Therefore, the synthesis of TG and fatty acid was stimulated by the alternation of emersion and submersion of thalli from sea water and eco-physiological conditions during summer: high temperature and light, and low concentration of nitrogen.

• 미생물학회지
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• 제32권3호
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• pp.202-207
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• 1994

Bacillus megaterium ATCC 14945의 penicillin G acylase 유전자의 염기배열을 결정하였다. 이 유전자에는 2,406 염기쌍으로 이루어진 하나의 open reading frame이 존재하는데, 개시코돈의 5' 위쪽에서 Shine-Dalgarno 배열과 promoter로 여겨지는 부분을 발견하였으며, 종결코돈의 3' Synechocystis sp. PCC 6803으로부터 광활성종속영양으로 생장할 수 없는 돌연변이체 PRM1을 분리하였다. PRM1을 혼합영양으로 배양하였을 경우에는 생장속도가 Synechocystis 6803과 거의 같았다. 그러나 PRM1을 하루에 5 분만 빛을 조사하면서 광활성종속영양으로 배양하였을 경우에는 전혀 생장하지 못하였다. 이러한 결과는 PRM1이 종속영양으로 생장하는데 필요한 대사능력에 이상이 있는 것이 아니라 생장에 필요한 광신호 전이 체계에 이상이 있음을 시사한다. PRM1의 plasmid 양상, 균체의 absorption spectra, 세포 내부와 외부의 형태 등은 Synechocystis 6803과 유사하였으나 여러 세포들을 함께 얽어매는 부정형 점액성 물질을 형성하지 않는 점이 달랐다.