• Title/Summary/Keyword: Lux

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Coregulation of lux Genes and Riboflavin Genes in Bioluminescent Bacteria of Photobacterium phosphoreum

  • Sung, Nack-Do;Lee, ChanYong
    • Journal of Microbiology
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    • v.42 no.3
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    • pp.194-199
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    • 2004
  • Investigation of the expression of the riboflavin (rib) genes, which are found immediately downstream of luxG in the lux operon in Photobacterium phosphoreum, provides more information relevant to the evolution of bioluminescence, as well as to the regulation of supply of flavin substrate for bacterial bioluminescence reactions. In order to answer the question of whether or not the transcriptions of lux and rib genes are integrated, a transcriptional termination assay was performed with P. phoxphoreum DNA, containing the possible stem-loop structures, located in the intergenic region of luxF and luxE ($\Omega$$\_$A/), of luxG and ribE ($\Omega$$\_$B/), and downstream of ribA ($\Omega$$\_$c/). The expression of the CAT (Chloram-phenicol Acetyl Transferase) reporter gene was remarkably decreased upon the insertion of the stem-loop structure ($\Omega$$\_$c/) into the strong lux promoter and the reporter gene. However, the insertion of the structure ($\Omega$$\_$B/) into the intergenic region of the lux and the rib genes caused no significant change in expression from the CAT gene. In addition, the single stranded DNA in the same region was protected by the P. phosphoreum mRNA from the Sl nuclease protection assay. These results suggest that lux genes and rib genes are part of the same operon in P. phosphoreum.

Effect of Light on the Sclerotial Formation of Sclerotinia sclerotiorum(Lib.) de Bary (균핵병균(Sclerotinia sclerotiorum(Lib.) de Bary)의 균핵형성에 미치는 광선의 영향)

  • Kim Ki Chung
    • Korean journal of applied entomology
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    • v.15 no.3 s.28
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    • pp.153-159
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    • 1976
  • Present paper was attempted to investigate the effects of the light on the sclerotium formation of some isolates of Sclerotinia sclerotiorum(Lib.) do Bary from lettuce, cucumber and rape. The investigations were performed in the both aspects inducing sclerotial primordia from the mycelial colony and developing such primordia. The cultures were grown on potato-dextrose agar and were treated with day-light fluorescent lamps. In the continuous light illumination for 21 days, numbers of sclerotial primordia and matured sclerotia were increased with increasing the light intensity up to about 500 Lux, but on the contrary the dry-weight of matured sclerotia was decreased. In the 800 Lux illumination, induction of the primordia was extremely depressed, and then matured sclerotia were almost not produced. Short-time illumination for 48 hours, although the light intensity was as high as 5000 Lux, increased the numbers of sclerotial primordia and matured sclerotia. Dry-weight of matured sclerotia, however, was slightly increased only at low intensity of 160 Lux. On the other hand, the light shock which u·as alternatively on-of light every one minute for 48 hours increased the number and dry-weight of sclerotia produced, but the former was more effective at 500 Lux shock and the later more effective at 160 Lux shock.

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Growth and Yield Response of Rice Cultivars to Different Night illumination Intensities (야간조명 광도에 따른 벼 품종별 생육 및 수량 반응)

  • 김충국;조현숙;서종호;최성호;변종영
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.47 no.6
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    • pp.471-474
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    • 2002
  • This experiment was conducted to investigate the response of rice growth and grain yield to night illumination. Three cultivars Heugjubyeo (early maturing), Hwaseongbyeo (medium maturing), and Ilpumbyeo(mid-late maturing) were tested under different light intensities ranging 1.0 to 20.0 lux (0.3 to 5.6 $1\mu\textrm{W}$ $cm^{-2}$). Awn length of all cultivars became longer as night illumination intensity increased; 4.09 cm under 10-20 lux compared to 1.93cm under 2 lux in Hwaseongbyeo. However culm and spike length ere not affected by night illumination. Night illumination delayed flowering by 3 days in Heugjinjubyeo, 5 days in Hwaseongbyeo, and 9 days in Ilpumbyeo at 10-20 lux compared to that at 2 lux. Grain yield was reduced by 10.0% in Heugjinjubyeo, 17.7% in Hwaseongbyeo, and 20.7% in Ilpumbyeo at 10-20 lux compared to 2 lux condition.

Expression and DNA Sequence of the Gene Coding for the lux-specific Fatty Acyl-CoA Reductase from photobacterium phosphoreum

  • Lee, Chan-Yong;Edward A. Meighen
    • Journal of Microbiology
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    • v.38 no.2
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    • pp.80-87
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    • 2000
  • The nucleotide sequence of the luxC gene coding for lux-specific fatty acyl-CoA reductase and the upstream DNA (325bp)of the structural gene from bioluminescent bacterium, Photobacterium phosphoreum, has been deternubed. An open reading frame extending for more than 20 codons in 325 bp DNA upstream of luxC was not present in both directions. The lux gene can be translated into a polypeptide of 54 kDa and the amino acid sequences of lux specific reductases of P. phosphoreum shares 80, 65, 58, and 62% identity with those of the Photobacterium leiognathi, Vibrio fischeri, Vibrio harveyi, and Xehnorhabdus luminescenens reductases, respectively. Analyses of codon usage, showing that a high frequency (2.3%) of the isoleucine codon, AUA, in the luxC gene compared to that found in Escherichia coli genes (0.2%) and its absence in the luxA and B genes, suggested that the AUA codon may play a modulator role in the expression of lux gene in E. coli. The structural genes (luxC, D, A, B, E) of the P. phosphoreum coding for luciferase (${\alpha}$,${\beta}$) and fatty acid reductase (r, s, t) polypeptides can be expressed exclusively in E. coli under the T7 phage RNA polymerase/promoter system and identificationof the [35S]methionine labelled polypeptide products. The degree of expression of lux genes in analyses of codon usage. High expression of the luxC gene could only be accomplished in a mutant E. coli 43R. Even in crude extracts, the acylated acyl-CoA reductase intermediate as well as acyl-CoA reductrase activities could be readily detected.

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Response of Electrocardiogram of Mirror Carp, Cyprinus carpio to Light Stimuli (광 자극에 대한 향어의 심전도)

  • 양용림;김영기
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.37 no.2
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    • pp.124-132
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    • 2001
  • The authors examined the response of electrocardiogram (ECG) of Mirror carp, Cyprinus carpio [Linnaeus] to light stimuli. The experiments were performed in such a way that three levels of light stimuli (10, 100, and 400 lux) were given to fishes with an electrode inserted into their bodies and then their ECGs were recorded continuously for 60 minutes. The results which are divided into by day and by night and then analyzed by fishes conditions are as follows : 1. Mirror carps reached a stable condition 5 minutes after anesthesia. In this condition, the average heart rate was 64.9 beat/min by day and 65.3 beat/min by night. And the average action potential was 36.9 nV by day and 32.9 nV by night. 2. The average heart rate by three levels of light stimuli was, 1) In a stimulus condition, in case of 10 lux 68.7 beat/min by day and 46.0 beat/min by night, in case of 100 lux 53.4 beat/min by day and 44.1 beat/min by night, and in case of 400 lux 53.2 beat/min by day and 40.1 beat/min by night. 2) In a recovery condition, in case of 10 lux 67.9 beat/min by day and 57.2 beat/min by night, in case of 100 lux 68.8 beat/min by day and 61.0 beat/min by night, and in case of 400 lux 69.6 beat/min by day and 63.6 beat/min by night. 3. The average action potential by three levels of light stimuli was, 1) In a stimulus condition, in case of 10 lux 59.1 nV by day and 24.0 nV by night, in case of 100 lux 26.8 nV by day and 45.6 nV by night, and in case of 400 lux 71.7 nV by day and 14.4 nV by night. 2) In a recovery condition, in case of 10 lux 38.8 nV by day and 27.3 nV by night, in case of 100 lux 29.0 nV by day and 39.3 nV by night, and in case of 400 lux 66.4 nV by day and 21.4 nV by night.

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Flowering Response to Light Intensity and Night Interruption in Perilla (광강도와 야간조명에 따른 들깨의 개화 반응)

  • Oh, Myung-Kyu;Yu, Sug-Jong;Kim, Jong-Tae;Oh, Youn-Sup;Cheong, Young-Keun;Jang, Young-Sun;Park, Inn-Jin;Park, Keun-Yong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.40 no.5
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    • pp.543-547
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    • 1995
  • This study was conducted to light intensity and night interruption on leaf production in perilla. Using two cultivars ; og-dong and Yeup-sil. The present studies were conducted to investigate effect of the light intensity and night interruption for prolongation of vegetative growth by flowering inhibition in the National Honam Crop Experiment Station, R. D. A, Iri, Korea. The results are summarized as followes, varietal differences of days to flower initiation were not significant by the light intensity and night interruption, however differences of days to flower initiation light intensity or night interruption treatment were higly significant. Flowering of perilla was prolongated in high light intensity and in long night interruption. Between the factors treated flowering of perilla was more influenced by light intensity than night interruption. Days to flower initiation of perilla were light intensity(0.5∼1 Lux) in 30 mins night interruption, however 3∼10 light intensity in 60 mins night interruption and 30∼100 Lux light intensity in 10, 30, 60 mins night interruption treatment were not flowering. Plant height, leaf area and dry weight of perilla were the highest in 30∼100 Lux light intensity treatment than in the other treatments. The results would be avaliable establish year-round production methods for low cost of perilla leaf.

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Growth Responses and Introduction Plan of Interior Landscape Plants under Light Intensity of Fluorescent Light and Sunlight (형광등과 자연광의 광도에 따른 실내조경식물의 생육반응과 도입 방안)

  • Choi Kyoung-Ok;Lee Sang-Woo
    • Journal of the Korean Institute of Landscape Architecture
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    • v.33 no.4 s.111
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    • pp.119-128
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    • 2005
  • This study was carried out to obtain fundamental information of growth response of interior landscape plants under a fluorescent lighting, a sunlight at indoor. Ficus elastica Roxb. vu. decora Hort, Spathiphyllum 'Clevelandii', Codiaeum variegatum Blume var. pictum Mvell. Arg. 'Exalant' and Cordyline terminalis Kunth var. red edge Hort were examined under 100lux, 500lux, 1,000lux and 2,000lux light intensity consisted of fluorescent lighting and sunlight at indoor condition. Result of experiments are as follows; 1. A Ficus elastica Roxb. var. decora Hort plant growth status was better showed under fluorescent lighting than sunlight. A plant growth status showed the best result under 2,000lux light intensity of fluorescent lighting in cases of all conditions. 2. A Spathiphyllum 'Clevelandii' showed the best effective adaptations under law intensity among experimental plants. A Spathiphyllum 'Clevelandii', plant growth status was better showed under fluorescent lighting than sunlight. A plant growth status showed the best result under 1,000lux light intensity of fluorescent lighting in cases of all conditions. 3. It need the best high establishment of fluorescent lighting among experimental plants for good plant growth. A Codiaeum variegatum Blume var. pictum Mvell. Arg. 'Exalant' plant growth status was better showed under fluorescent lighting than sunlight. A plant growth status was better showed under high light intensity in case of same light source. A plant growth status showed the best result under 2,000lux light intensity of fluorescent lighting. 4. A Cordyline terminalis Kunth var. red edge Hort plant growth status was better showed under fluorescent lighting than sunlight. but, A plant growth status was better showed under $500lux\sim1,000lux$ than 2,000lux in cases of all intensity of fluorescent lighting. while, A plant growth status was better showed under $1,000lux\sim2,000lux$ in cases of all intensity of sunlight.

Effect of LED Lighting Intensity on Productivity, Blood Parameters and Immune Responses in Dairy Cows (LED 점등 세기가 젖소의 생산성, 혈액 매개변수 및 면역 반응에 미치는 영향)

  • Park, Jin-Ryong;Belal, Shah-Ahmed;Na, Chong-Sam;Shim, Kwan-Seob
    • Korean Journal of Organic Agriculture
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    • v.27 no.2
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    • pp.161-171
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    • 2019
  • A light-emitting diode (LED) is most efficient in terms of economic benefits. The aim of the present study was to evaluate the effects of LED lighting intensity on milk production, milk composition, and the immune response of Holstein cows. Thirty-eight lactating cows were assigned to four experimental groups: control group (exposed natural daylight without LED light) and three LED treatment group (50 lux; natural daylight and 6 h LED light of 50 lux intensity, 100 lux; natural daylight and 6 h LED light of 100 lux intensity, 200 lux; natural daylight and 6 h LED light of 200 lux intensity). There was a significant effect on the decrease ratio in milk production in 200 lux group. Lactose was significantly increased in 100 lux than the other LED treated groups. In addition to the hemolytic biochemical analysis, AST and β-HB were significantly increased in the 50 lux than the other groups. Prolactin and IGF-1 levels were significantly increased in 200 lux compared to other groups. Besides, cortisol was significantly higher in 50 lux and lowered in the 200 lux than the control, while IgA and IgG were not significant among the groups. Therefore, it was concluded that LED lighting intensity had some impact on blood parameters and immune responses in dairy cows with increased milk production.

Light Conditions for Suitable Growth of Urban Interior Plants - In Case of Green House within Kyobo Building, Seoul - (도심 실내조경 식물의 적절한 생육에 필요한 광조건 - 서울시 광화문 교보생명빌딩 그린하우스를 대상으로 -)

  • Lee, Kyong-Jae;Choi, Jin-Woo;Pae, Ho-Bong;Kang, Hyun-Kyoung
    • Journal of the Korean Institute of Landscape Architecture
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    • v.37 no.3
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    • pp.113-124
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    • 2009
  • This study has attempted to calculate the intensity of illumination for the optimal growth environment of indoor plants after analyzing both damage to plant species and growth conditions as impacted by light conditions for the Kyobo Life Insurance greenhouse. The optical intensity of illumination has been estimated after investigating the problems of growth conditions based on an analysis of illumination by light condition, dead tree replacement cycle(weeks) and rate of damage of plant species. According to the investigation of illumination, the lowest difference was observed between the shaded spot in the south(531lux) and the sunny spot(602lux) while the largest difference(nearly 500lux) was detected between the shaded spot in the central area(210lux) and the sunny spot(782lux). According to an analysis of dead trees from 1990 to 2004, in terms of dead tree replacement cycle, Viburnum awabuki was the highest(161weeks), followed by Phyllostachys spp.(84weeks), Camellia japonica and Ternstroemia japonica(40weeks). Regardless of plant species, damage rate of plant were lower in the shaded spot and higher in the sunny spot. According to correlation and regression analyses with the intensity of illumination as an independent variable and the damage rate of plant species as a dependent variable, the damage rate of plant species increased as the intensity of illumination decreased. A dramatic decline in the rate of damage was observed at $500{\sim}600lux$. At 700lux, it reached the lowest level.

The Lux Genes and Riboflavin Genes in Bioluminescent System of Photobacterium leiognathi Are under Common Regulation

  • Sung, Nack-Do;Lee, Chan-Yong
    • Journal of Photoscience
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    • v.11 no.1
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    • pp.41-45
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    • 2004
  • The key riboflavin synthesis genes are located immediately downstream of luxG in the lux operon from Photobacterium leiognathi. It is of interest that a site capable of forming a rho-independent terminator does not appear to be present between luxG and ribE in our previous data. These results raise the question of whether the transcription of lux and rib genes is integrated or not. In order to answer the question, in vivo transcriptional assay and Southern blot were examined. These studies demonstrate that neither transcriptional terminator nor promoter site is present in the intergenic region between of lux and rib genes as well as that the riboflavin genes are single copy in a chromosome of Photobacterium leiognathi.

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