Neurospora 의 생육시기에 따른 호흡능의 변화와 자외선 감수성과의 상관관계

이영녹 (Yung Nok Lee) 한국식물학회 1963 Journal of Plant Biology Vol.6 No.4

LEE, Yung Nok (Dept. of Biology, Korea University) Changes in respiratory activity and the sensitivity to ultraviole light of Neurospora cells at different growing stages. Kor. Jour. Bot. Ⅵ (4) : 1-4. 1963. Using conidia of Neurospora, changes in respiratory activities and the sensitivity to the ultraviolet light of the cells at different growing stages were measured by manometric methods, and the correlation between them was observed. Efficiency in the utilization of various carbon sources, such as, glucose, sucrose, maltose, starch and sodium acetate, in growth and exogenous respiration of N. crassa was also determined. Growth rate of N. crassa was decreased considerably in the medium containing sodium acetate than in the glucose medium and was almost zero in the lactose medium, whereas the utilization of sucrose. maltose and starch was very high, as that of glucose. Respiratory activities of the cells veried considerably depending upon their different growing stages. Actively growing hyphae exhibited the greatest activity in exogenous glucose respiration, followed by germinating and activated conidia in decreasing order. There was no proportional relationship between the dose of ultraviolet light irradiated and its effect on the respiratory activity of the cells, though the more the dose of ultraviolet light, the more the injuri. The sensitivity of the cells to ultraviolet light varied with the different respiratory activities of the cells linked to the deve1opmental stages. In general, the more actively glowing cells having high respiratory activities exhibited the more serious injury.

Chlorella 의 생리적 , 생화학적 제활성에 미치는 γ - 선의 영향

이영녹 (Yung Nok Lee) 한국식물학회 1964 Journal of Plant Biology Vol.7 No.3

LEE, Yung Nok (Dept. of Biology, Korea University) Effects of Cobalts-60 γ-ray irradiation on the physiological and biochemical activities of Chlirella. Kor. J. Bot., Ⅶ(3):9-14, 1964 The sensitivities of Chlorella ellipsoidea to r-ray from Cobalt-60 were determined by measuring the photosynthetic and respiratory activities and the changes in phosphate contents in various fractions of the irradiated cells, which were further grown in a standard medium after irradiation, were compared to those of non-irradoated normal cells. The photosynthetic and respiratory activities of the cells were almost inversely propotional to the dose of γ·ray irradiated and the photosynthetic activity was more sensitive than the respiratory activity of the cells. The most sensitive to γ-ray was growth activity, followed by photosynthesis, exogenous and endogenous respirations of the cells in decreasing order. Chlorella cells were so resistant to γ-ray compared with other organisms that about 280,OO0 r dose of γ-ray irradiation was necessary to reduce as much as half the subsequent photosynthetic activity. When the irradiated algae were further cultured in a standard medium, the phosphate contents in the fraction of DNA, RNA and phosphoprotein decreased considerably compared with those of non-irradiated normal cells, while the phosphate contents in the fraction of polyphosphates increased than those of control. Therefore, it was deduced that γ-ray inhibited the synthesis of DNA from polyphosphates, that the synthetic activitied of RNA and protein were decreased owing to either these indirect effect on DNA synthesis or the direct effect of γ-ray itself, and that the growth of Chlorella cells were consequently retarded.

Chlorella 세포의 핵산 인단백질의 생합성에 미치는 마그네슘의 결핍 (缺乏)효과

이영녹(Yung Nok Lee),이종삼(Chong Sam Lee) 한국식물학회 1968 Journal of Plant Biology Vol.11 No.1

Chlorella ellipsoidea were grown in a Mg-free medium. Aliquots of the algal cell were taken out at the beginning and predetermined time intervals during the culture and were analyzed the contents of phosphate in various fractions of the cell constituents. The results obtained were compared with those of the control. When Chlorella cells were grown in a Mg-free medium, the contents of phosphate in the DNA protein, RNA-polyphosphate complex, nucleotidic-labileP, and PCA-soluble, fractions decreased compared with those of the control, while the content of acid insoluble polyphosphate increased signiscantly. On the otherhand, RNA-P and lipid-P showed the tendency of decrease at the early stage of the culture, but they were increased more than those in the control as culutre proceeds. It is showed that phosphate turnover from acid-insoluble polyphosphate into DNA, protein, and RNA-polyphosphate compiex was inhibited by magnesium-deficiency of the cells.

pTi-12 를 함유한 한국산 Agrobacterium tumefaciens KU12 의 숙주범위

전경아(Geoung A Jun),이영녹(Yung Nok Lee),심웅섭(Woong Seop Sim) 한국식물학회 1990 Journal of Plant Biology Vol.33 No.2

In order to investigate the host range of Agrobacterium tumefaciens KU12 containing pTi-12, 28 species of dicotyledonous plants were infected with KU12, A136 without Ti plasmid and A348 containing pTi A6, respectively. KU12 and A348 induced tumor in 20 species and 14 species, respectively. This result showed that KU12 has a wide host range. Therefore, it was confirmed that KU12 and pTi-12 are very useful for developing plant vector system having a broad host range.

燐酸缺乏培地에 있어서의 Chlorella 細胞內의 燐酸化合物의 轉換

李永祿,沈雄燮 한국식물학회 1966 Journal of Plant Biology Vol.9 No.1-2

Using the Chlorella cells which had been uniformly labeled with ^(32)P, the distribution of phosphorus in various fractions of cell material was investigated. Uniformly ^(32)P-labeled Chlorella cells were futher grown in a P-free medium, and some portions of the cells were taken out at intervals during the culture, and subjected to analyze the contents of ^(32)P in various fractions of the cell consituents. 2. Analysis of the ^(32)P-labeled Chlorella cells showed that the highest in P-content was the fraction of RNA followed by those of lipid, RNA-polyphosphate complex, acid-insoluble polypho-sphate, acid-soluble polyphosphate, DNA ana protein. 3. During the culture of ^(32)P-labeled Chlorella cells in a P-free medium, amounts of phosphate in DNA, protein and lipid fractions increased, while the P-contents in the fraction of RNA-polyphosphate cemplex decreased as well as those of acid-insoluble polyphosphate and acid-soluble polyphospate fractions. 4. It was inferred that phosphorus used in the syntheses of DNA aud protein was taken from polyphosphates of the cells, and RNA-polyphosphate complex would play an important role as a phosphate pool.

Cloning and Characterization of Two catA Genes in Acinetobacter lwoffii K24

CHUNG, YOUNG HO,HA, KWON-SOO,LEE, YUNG NOK,KIM, SEUNG IL,PARK, YOUNG-MOK,KIM, SOOHYUN,CHOI, JONG SOON,LEEM, SUN HEE,PARK, YONG KEUN 東亞大學校附設遺傳工學硏究所 1997 遺傳工學硏究 Vol.- No.6

Two novel type I catechol 1,2-dioxygenases inducible on aniline media were isolated from Acinetobacter lwoffii K24. Although the two purified enzymes, CDI₁and CDI₂, had similar intradiol cleavage activities, they showed different substrate specificities for catechol analogs, physicochemical properties, and amino acid sequences. Two catA genes, catA₁and catA₂, encoding by CDI₁ and CD I₂, respectively, were isolated from the A. lwoffii K24 genomic library by using colony hybridization and PCR. Two DNA fragments containing the catA1 and catA₂ genes were located on separate regions of the chromosome. They contained open reading frames encoding 33.4-and 30.4-kDa proteins. The amino acid sequences of the two proteins matched well with previously determined sequences. Interestingly, further analysis of the two DNA fragments revealed the locations of the catB and catC genes as well. Moreover, the DNA fragment containing catA₁ had a cluster of genes in the order catB₁-catC₁-catA₁ while the catB₂-catA₂-catC₂ arrangement was found in the catA₂ DNA fragment. These results may provide an explanation of the different substrate specificities and physicochemical properties of CDI₁ and CDI₂.