• 식물분류학회지
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• 제40권2호
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• pp.105-107
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• 2010

미나리아재비과(Ranunculaceae) 너도바람꽃속(Eranthis)중에서 우리나라에 자생하는 너도바람꽃(E. stellata Maxim.)과 변산바람꽃(E. byunsanensis B. Sun)을 대상으로 종자의 외부형태와 해부형태를 관찰하였다. 그 결과, 두 종간에 종자표면의 모용 발달 유무에서 뚜렷한 차이가 관찰되었다. 즉, 너도바람꽃의 종자는 표면에 단세포성 모용이 발달하지 않는 반면, 변산바람꽃은 종자표면에 표피세포 유래의 단세포성 모용이 잘 발달하는 특징이 확인되었다. 이것은 변산바람꽃을 신종으로 발표하면서 제시했던 형태적 특징 외에, 변산바람꽃을 특산종으로 강하게 지지할 수 있는 또 다른 명확한 형태적 특징이라고 판단된다. 아울러 이번 연구에서 재료의 미확보로 연구하지 못한 풍도바람꽃과 일본종 E. pinnatifida의 종자형태도 비교 연구되어야 할 것으로 생각된다.

• Environmental Engineering Research
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• 제15권1호
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• pp.3-7
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• 2010

To better understand the ecology of tetrade forming organisms (TFOs) floating in a large amount of dairy wastewater treatment plant (WWTP) effluent (sequencing batch reactor [SBR]) during the inefficient phosphorus (P) removal process of an enhanced biological P removal system, the TFOs from the effluent of a full scale WWTP were separated and attempts made to culture the TFOs in presence/absence of oxygen. The intact TFOs only grew aerobically in the form of unicellular short-rods. Furthermore, to identify the intact TFOs and unicellular short-rods the DNAs of both were extracted, analyzed using their denaturing gradient gel electrophoresis (DGGE)-profiles and then sequenced. The TFOs and unicellular short-rods exhibited the same banding pattern in their DGGE-profiles, and those sequencing data resulted in their identification as Acinetobacter sp. The intact TFOs appeared in clumps and packages of tetrade cells, and were identified as Acinetobacter sp., which are known as strict aerobes and efficient P-removers. The thick layer of extracellular polymeric substance surrounding Acinetobacter sp. may inhibit phosphate uptake, and the cell morphology of TFOs might subsequently be connected with their survival strategy under the anaerobic regime of the SBR system.

• Journal of Plant Biology
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• 제31권1호
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• pp.69-82
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• 1988

• Journal of Microbiology and Biotechnology
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• 제16권6호
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• pp.821-831
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• 2006

Unicellular green algae of the genus Haematococcus have been studied extensively as model organisms for secondary carotenoid accumulation. Upon environmental stress, such as strong irradiance or nitrogen deficiency, unicellular green algae of the genus Haematococcus accumulate secondary carotenoids in vesicles in the cytosol. Because secondary carotenoid accumulation occurs only upon specific environmental stimuli, there is speculation about the regulation of the biosynthetic pathway specific for secondary carotenogenesis. Because the carotenoid biosynthesis pathway is located both in the chloroplast and the cytosol, communication between both cellular compartments must be considered. Recently, the induction and regulation of astaxanthin biosynthesis in microalgae received considerable attention because of the increasing use of this secondary carotenoid as a source of pigmentation for fish aquaculture, as a component in cancer prevention, and as a free-radical quencher. This review summarizes the biosynthesis and regulation of the pathway, as well as the biotechnology of astaxanthin production in Haematococcus.

• 한국광과학회:학술대회논문집
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• 한국광과학회 2002년도 정기총회 및 제9회 광과학 학술심포지움 논문초록
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• pp.37-37
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• 2002

• Journal of Photoscience
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• 제2권1호
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• pp.31-35
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• 1995

Light signals in the form of intensity gradient, propagation direction, and wavelength elicit diverse mechanical responses ("photomechanical responese") in most organisms. The single cell ciliates, Stentor coeruleus and Blepharisma japonicum, are particularly sensitive to the light of visible wavelengths. In this paper, the way in which the seemingly sophisticated light signal transduction is triggered by the photosensory apparatus will be described in terms of the photoreceptor structure and photochemical function.

• ALGAE
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• 제26권2호
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• pp.167-180
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• 2011

The unicellular marine red alga Erythrolobus australicus sp. nov. (Porphyridiophyceae) was isolated into laboratory culture from mangroves in Queensland and New South Wales, Australia. The single multi-lobed red to rose-red plastid has more than one pyrenoid and lacks a peripheral thylakoid. Arrays of small electron dense globules occur along the thylakoids. The nucleus is peripheral with a central to eccentric nucleolus. Each Golgi body is associated with a mitochondrion. The spherical cells are positively phototactic with slow gliding movement. The psaA + psbA phylogeny clearly showed that E. australicus is a distinct species, which is closely related to E. coxiae. The chemotaxonomically relevant and most abundant low molecular weight carbohydrate in E. australicus is floridoside with concentrations between 209 and 231 ${\mu}mol g^{-1}$ dry weight. Traces of digeneaside were also detected. These various approaches help to understand the taxonomic diversity of unicellular red algae.

• ALGAE
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• 제26권1호
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• pp.3-20
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• 2011

The physiology of the unicellular green alga Dunaliella salina in response to abiotic stress has been studied for several decades. Early D. salina research focused on its remarkable salinity tolerance and ability, upon exposure to various abiotic stresses, to accumulate high concentrations of $\beta$-carotene and other carotenoid pigments valued highly as nutraceuticals. The simple life cycle and growth requirements of D. salina make this organism one of the large-scale commercially exploited microalgae for natural carotenoids. Recent advances in genomics and proteomics now allow investigation of abiotic stress responses at the molecular level. Detailed knowledge of isoprenoid biosynthesis mechanisms and the development of molecular tools and techniques for D. salina will allow the improvement of physiological characteristics of algal strains and the use of transgenic algae in bioreactors. Here we review D. salina isoprenoid and carotenoid biosynthesis regulation, and also the biotechnological and genetic transformation procedures developed for this alga that set the stage for its future use as a production system.

• ALGAE
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• 제26권4호
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• pp.277-288
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• 2011

The marine unicellular red algal genus Rhodella was established in 1970 by L. V. Evans with a single species R. maculata based on nuclear projections into the pyrenoid. Porphyridium violaceum was described by P. Kornmann in 1965 and transferred to Rhodella by W. Wehrmeyer in 1971 based on plastid features and the non-parietal position of the nucleus. Molecular and fine structural evidences have now revealed that Rhodella maculata and R. violacea are one species, so R. violacea has nomenclatural priority and the correct name is Rhodella violacea (Kornmann) Wehrmeyer. The status of families within Rhodellophyceae was examined. The order Dixoniellales and family Dixoniellaceae are emended to include only Dixoniella and Neorhodella. The order Rhodellales and family Rhodellaceae are emended to include Rhodella and Corynoplastis. Glaucosphaera vacuolata Korshikov and the Glaucosphaeraceae Skuja (1954) with an emended description are transferred to the Glaucosphaerales ord. nov.

• 한국수소및신에너지학회논문집
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• 제22권5호
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• pp.663-670
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• 2011

Under a daily photoperiod of 14h light and 10h dark synchronization of cell cycle in Korean Cyanothece spp. strains and $Synechococcus$ sp. strain Miami BG043511 was analyzed as to be applicable to enhanced hydrogen production. For all strains peaks of double cell were observed during the light period of a daily cycle. Peaks of maximal cell size measured by a coulter counter appeared at the peak of double cells observed under light microscope reconfirming the synchronization of daily cell cycle. The cell cycle synchronization became weakened within two days when treated with continuous illumination. Rapid detection of the peak time of double cell percentage by coulter counters may contribute to quasi-realtime feedback control for efficient production of photobiological hydrogen by unicellular cyanobacterial strains.