Three ORF-Containing Group I Introns in Chloroplast SSU of Caulerpa sertularioides (Ulvophyceae) and Their Evolutionary Implications

이정호,JamesR.Manhart2 한국조류학회I 2003 ALGAE Vol.18 No.3

Except for a group I intron in trnL-uaa occuring in eubacteria and plastids, group I introns are rarely documented in plastid genomes. Here, we report that a green alga, Caulerpa sertularioides, contains three group IA3 introns in the 16S gene (cpSSU), CS-cpSSU.i1, CS-cpSSU.i2 and CS-cpSSU.i3. Each intron has an open reading frame with LAGLIDADG motifs. CS-cpSSU.i1orf and CS-cpSSU.i3orf occur at Loop 6 in the intron secondary structure and CScpSSU. i2orf at Loop 8. CS-cpSSU.i1orf and CS-cpSSU.i2orf contain both LAGLI-DADG motifs but CS-cpSSU.i3orf has only one. CS-cpSSU.i1 and CS-cpSSU.i2 share the insetion sites and the ORFs at Loop 6 and 8 with CpSSU·1 and CpSSU·2 introns of Chlamydomonas pallidostigmatica (Chlorophyceae). In contrast, CS-cpSSU.i3, containing 28 copies of GAAATAT at Loop 6, is a novel intron found only in Caulerpa sertularioides. Possible scenarios of the evolution of the three introns and their possible use in systematic research are discussed.

Temperature ranges for survival and growth of juvenile Saccharina sculpera (Laminariales, Phaeophyta) and applications for field cultivation

Soo Hong Kim,Young Dae Kim,Mi Sook Hwang,Eun Kyoung Hwang,유현일 한국조류학회I 2021 ALGAE Vol.36 No.4

Saccharina sculpera is highly valued for human consumption and value-added products. However, natural resourcesof this kelp have decreased sharply and it is in danger of extinction. Resources recovery through cultivation is beingtrialed to enable the sustainable use of this species. In this study, the temperature range for survival and optimal growthof juvenile S. sculpera was identified and applied to field cultivation. This study investigated the survival and growthof juvenile S. sculpera under six temperatures (i.e., 5, 10, 15, 16, 18, and 20°C) and two light intensities (i.e., 20 and 40µmol photons m-2 s-1) in an indoor culture experiment. In these experiments, the blade length decreased at 16°C underthe both light intensities. The thalli died at 20°C and 20 µmol photons m-2 s-1, and at 18‒20°C and 40 µmol photons m-2s-1. During the field cultivation, early growth of S. sculpera was highest at the 5 m depth and growth decreased as thewater depth increased. When the initial rearing depth was maintained without adjustment throughout the cultivationperiod (from December to October), all the cultivated S. sculpera plants died during August and September. However, S. sculpera plants lowered from 5 to 15 m and grew to 90.8 ± 13.1 cm in July. The seawater temperature at 15 m depth wassimilar to the upper level of thermal tolerance demonstrated by juvenile S. sculpera in the indoor culture experiments(16°C or lower). The plants were subsequently lowered to 25 m depth in August, which eventually led to their matura tion in October. The present study confirmed that improved growth rates and a delay in biomass loss can be achieved byadjusting the depth at which the seaweeds are grown during the cultivation period. These results will contribute to theestablishment of sustainable cultivation systems for S. sculpera.

한국산 홍조류 가는곱슬이(Plocamium cartilagineum)의 형태분류학적 고찰

이선주,김명숙 한국조류학회I 2022 수생생물 Vol.2 No.2

홍조식물 곱슬이속은 열대에서 추운 온대지역까지 널리 분포하고 주로 조하대 암반에서 생육하며 한국에는 6종이 보고되었다. 그 중에서 가는곱슬이(Plocamium cartilagineum)는 한국의 동해, 남해, 제주도에 분포하는데 생육환경에 따른 형태 변이로 인하여 종의 정확한 동정이 어렵다. 따라서 본 연구는 한국산 가는곱슬이를 대상으로 연속 편생지 내 소지의 수, 기저소지의 형태와 크기, 낭과와 사분포자탁을 기준으로 하여 주요 식별형질의 종내 형태 변이를 관찰하였다. 그 결과 기준생육지인 유럽산(네덜란드)은 한국산 가는곱슬이에 비해 엽상체의 크기가 2배 정도 더 크며, 그 외에 사분포자탁의 형태와 낭과 및 기저소지의 크기에서 차이를 보였다. 또한 한국 동해안의 엽상체는 남해안의 개체들 보다 크기가 작고 주축의 폭이 넓으며 기저소지가 짧은 특징을 나타내었다. 본 연구의 결과를 바탕으로 한국산 가는곱슬이의 정확한 분류학적 위치확립을 위하여 향후, 추가적인 형태분석을 포함한 분자계통학적 연구가 필요하다. The red algal genus Plocamium occurs in the world from tropical area to the cold temperate region, as well as in the Northwest Pacific. In Korea, there are six species of the genus Plocamium reported. Among them Plocamium cartilagineum (Linnaeus) P. S. Dixon inhabits on rocky substrate in the intertidal zone with extreme morphological variation. We compared the morphology of P. cartilagineum from Netherlands (Europe) as a type locality to Korean entity in order to investigate taxonomic identity. The size of the thallus from Netherlands was about twice as large as that of the Korean specimen. Futhermore, we noticed the differences in the morphology of tetrasporangial stichidia, size of cystocarp, and the width of lower branchlet between two entities. In addition, the specimens of P. cartilagineum collected from the eastern and southern coast of Korea show the different characteristics in habit and size of lower branchlet. Based on this result, we conclude that additional morphological and molecular phylogenetic studies are required to recognize as natural entities and to resolve a taxonomic status of P. cartilagineum from Korea.

울릉도에서 분리한 토착 미세조류 Coelastrella rubescens KNUA201의 배양 및 생화학적 특성 연구

구기연,도정미,윤호성 한국조류학회I 2023 수생생물 Vol.3 No.2

미세조류는 광합성을 통해 고속 성장을 이루며 동시에 고부가가치 산물을 생성할 수 있는 특징을 지니고 있다. 이러한 특징으로 인해 최근의 탄소중립시대에 말미암아 에너지 응용 산업에서 다양한 주목을 받고 있다. 본 연구에서는 대한민국 울릉도에서 토착 담수 미세조류 생물자원 배양주를 확보하였으며, 형태학적 및 18S rRNA, ITS, tufA 서열을 이용한 분자생물학적 동정 결과를 바탕으로 순수 분리된 KNUA201 균주가 Coelastrella rubescens임을 밝혔다. C. rubescens KNUA201 균주를 BG-11 배지에서 1~3%의 CO2를 공급하여 7일간 배양하였으며 이를 통해 1.34 g L–1의 건중량을 확보하였다. 7일 배양 후 수확한 바이오매스는 동결건조 후 원소분석을 진행하였으며 결과적으로 25.1 MJ kg–1로 확인되어 곡물계 및 목질계와 같은 이전세대 바이오매스보다 상대적으로 높은 열량값을 지니고 있음을 확인하였다. 생화학적 조성분석에서 약 59%의 높은 단백질 함량을 지닌 것으로 파악되었으며, GC/MS를 이용한 지방산 결과에서는 상업적으로 이용가능성이 높은 알파 리놀렌산(C18:3 (ω3))의 성분이 30.6%로 가장 높게 나타났다. 이러한 결과들을 토대로 울릉도에서 순수분리된 C. rubescens KNUA201 미세조류 균주는 차세대 바이오 에너지 연료, 식품 첨가물, 기능 식품 원료를 공급할 수 있는 생물자원으로서 다양한 활용 가능성에 대한 토대를 제공할 수 있을 것으로 생각된다. Microalgae have characteristics of the capability of achieving rapid growth through photosynthesis and also could generate high-value products. Owing to these characteristics, microalgae are considered promising candidates in the energy application industry, particularly in the recent era of carbon neutrality. In this study, we identified indigenous sample collected from Ulleungdo Island fresh water pond as Coelastrella rubescens based on morphological feature and ITS, tufA, 18S rRNA sequences analysis from isolated strain KNUA201. 1.34 g L–1 of C. rubescens KNUA201 biomass was obtained which was grown in BG-11 media with 1~3% of CO2 for 7 days. We verified that the biomass sample, which was freeze-dried for elemental analysis after 7 days of incubation, has 25.1 MJ kg–1 of high calorific value exceeding former generation biomass such as crops and woods. Besides, mass percent of protein was 59% by biochemical analysis, α-linolenic acid (C18:3 (ω3)) accounts for 30.6% which was the highest content result from GC/MS fatty acid analysis. Based on our screening of isolated C. rubescens KNUA201 from Ulleungdo Island, we consider isolated strain have numerous usability as next generation bioenergy fuel, food additive, raw material for functional food.

New distributional record for Pyropia koreana: confirmed to occur on the South Island, New Zealand

Wendy A. Nelson,Judith E. Sutherland,Mi Sook Hwang,Han-Gu Choi 한국조류학회I 2014 ALGAE Vol.29 No.3

An epiphytic bladed member of the Bangiales was found growing in Christchurch (South Island, New Zealand). Molecular sequence data and morphological comparisons revealed that the New Zealand specimens belong to the species Pyropia koreana (M. S. Hwang & I. K. Lee) M. S. Hwang, H. G. Choi, Y. S. Oh & I. K. Lee. This is the first record of Py. koreana in the southern hemisphere and a new record of an introduced species in New Zealand.

Bioaccumulation of copper and zinc by the giant kelp Macrocystis pyrifera

La Kenya Evans,Matthew S. Edwards 한국조류학회I 2011 ALGAE Vol.26 No.3

This study examined the bioaccumulation of the heavy metals copper (Cu) and zinc (Zn) by the giant kelp, Macrocystis pyrifera, by exposing meristematic kelp tissue to elevated metal concentrations in seawater within laboratory aquaria. Specifically, we carried out two different experiments. The first examined metal uptake under a single, ecologically-relevant elevation of each metal (30 ppb Cu and 100 ppb Zn), and the second examined the relationships between varying levels of the metals (i.e., 15, 39, 60, 120, 240, and 480 ppb Cu, and 50, 100, 200, 300, 500, and 600 ppb Zn). Both experiments were designed to contrast the uptake of the metals in isolation (i.e., when only one metal concentration was elevated)and in combination (i.e., when both metals’ concentrations were elevated). Following three days of exposure to the elevated metal concentrations, we collected and analyzed the M. pyrifera tissues using inductively coupled plasma atomic emissions spectroscopy. Our results indicated that M. pyrifera bioaccumulated Cu in all treatments where Cu concentrations in the seawater were elevated, regardless of whether Zn concentrations were also elevated. Similarly, M. pyrifera bioaccumulated Zn in treatments where seawater Zn concentrations were elevated, but this occurred only when we increased Zn alone, and not when we simultaneously increased Cu concentrations. This suggests that elevated Cu concentrations inhibit Zn uptake, but not vice versa. Following this, our second experiment examined the relationships among varying seawater Cu and Zn concentrations and their bioaccumulation by M. pyrifera. Here, our results indicated that, as their concentrations in the seawater rise, Cu and Zn uptake by M. pyrifera tissue also rises. As with the first experiment,the presence of elevated Zn in the water did not appear to affect Cu uptake at any concentration examined. However, although it was not statistically significant, we observed that the presence of elevated Cu in seawater appeared to trend toward inhibiting Zn uptake, especially at higher levels of the metals. This study suggests that M. pyrifera may be useful as a bio-indicator species for monitoring heavy metal pollution in coastal environments.

한국 서남해안 신안군 가거도 인근 무인도서의 하계 조간대 해조상 및 수직분포

류바다,김영식 한국조류학회I 2021 수생생물 Vol.1 No.1

한국 서남해안 신안군에 위치한 가거도 인근 9개 무인도서의 조간대에 생육하는 해조류를 파악하고자 2012년 7월 조사를 수행하였다. 조사결과 녹조류 1종, 갈조류 6종, 홍조류 26종이 출현하여 총 33종이 채집 및 동정되었다. PRIMER 5.0을 이용하여 유사도지수에 따른 군집분석을 실시한 결과 유의성 45%에서 크게 세 개의 그룹으로 나누어졌다. 가거도 인근 무인도의 조간대 생육하는 해조류의 수직분포를 보면 상부에서는 패(Ishige okamurae), 불등풀가사리(Gloiopeltis furcata), 참풀가사리(Gloiopeltis tenax), 중부에서는 작은구슬산호말(Corallina pilulifera), 진두발(Chondrus ocellatus), 하부에서는 톳(Sargassum fusiforme), 미역(Undaria pinnatifida), 작은구슬산호말이 우점하여 출현하였다. The objective of this study was to clarify marine algae of 9 uninhabited islands in Gageo, Sinan-gun area, south western coast of Korea from July 2012. As a result, a total of 33 species – 1 green, 6 browns and 26 reds – was identified. As a result of performing cluster analysis according to the similarity index using PRIMER 5.0, it was largely divided into three main groups at 45% of significance. The vertical distribution pattern of intertidal marine algae represented three distinct zones; Ishige okamurae, Gloiopeltis furcata, Gloiopeltis tenax – Corallina pilulifera, Chondrus ocellatus – Sargassum fusiforme, Undaria pinnatifida, Corallina pilulifera.

Costulariella, a new substitute name for Costularia Ju. Petrov et I. Gussarova (Laminariales, Phaeophyceae)

Nina G. Klochkova,Tatyana A. Klochkova 한국조류학회I 2010 ALGAE Vol.25 No.4

Costularia Ju. Petrov et I. Gussarova, published in 1970, is a preoccupied name by Clarke, 1898 for a genus of monocotyledonous flowering plants in the family Cyperaceae (Magnoliophyta) and thus illegitimate. Costulariella nom. nov. is proposed as a replacement. The distribution and morphology of this little-known species are discussed.

Effects of future climate conditions on photosynthesis and biochemical component of Ulva pertusa (Chlorophyta)

강은주,김광용 한국조류학회I 2016 ALGAE Vol.31 No.1

Ulva pertusa, a common bloom-forming green alga, was used as a model system to examine the effects of elevated carbon dioxide (CO2) and temperature on growth and photosynthetic performance. To do this, U. pertusa was grown under four temperature and CO2 conditions; ambient CO2 (400 μatm) and temperature (16°C) (i.e., present), elevated temperature only (19°C) (ET; i.e., warming), elevated CO2 only (1,000 μatm) (EC; i.e., acidification), and elevated temperature and CO2 (ET and EC; i.e., greenhouse), and its steady state photosynthetic performance evaluated. Maximum gross photosynthetic rates (GPmax) were highest under EC conditions and lowest under ET conditions. Further, ET conditions resulted in decreased rate of dark respiration (Rd), but growth of U. pertusa was higher under ET conditions than under ambient temperature conditions. In order to evaluate external carbonic anhydrase (eCA) activity, photosynthesis was measured at 70 μmol photons m−2 s−1 in the presence or absence of the eCA inhibitor acetazolamide (AZ), which inhibited photosynthetic rates in all treatments, indicating eCA activity. However, while AZ reduced U. pertusa photosynthesis in all treatments, this reduction was lower under ambient CO2 conditions (both present and warming) compared to EC conditions (both acidification and greenhouse). Moreover, Chlorophyll a and glucose contents in U. pertusa tissues declined under ET conditions (both warming and greenhouse) in conjunction with reduced GPmax and Rd. Overall, our results indicate that the interaction of EC and ET would offset each other’s impacts on photosynthesis and biochemical composition as related to carbon balance of U. pertusa.

Revisiting the Parvilucifera infectans / P. sinerae (Alveolata, Perkinsozoa) species complex, two parasitoids of dinoflagellates

전부성,남승원,김선주,박명길 한국조류학회I 2018 ALGAE Vol.33 No.1

Members of the family Parviluciferaceae (Alveolata, Perkinsozoa) are the well-known dinoflagellate parasitoids along with Amoebophrya ceratii species complex and parasitic chytrid Dinomyces arenysensis and contain six species across three genera (i.e., Parvilucifera infectans, P. sinerae, P. rostrata, and P. corolla, Dinovorax pyriformis, and Snorkelia prorocentri) so far. Among Parvilucifera species, the two species, P. infectans and P. sinerae, are very similar or almost identical each other morphologically and genetically, thereby make it difficult to distinguish between the two. The only main difference between the two species known so far is the number of sporangium wall (i.e., 2 layers in P. infectans vs. 3 layers in P. sinerae). During sampling in Masan bay, Korea during the spring season of 2015, the dinoflagellate Akashiwo sanguinea cells infected by the parasite Parvilucifera were observed and this host-parasite system was established in culture. Using this culture, its morphological and ultrastructural features with special emphasis on the variation in the number of sporangium wall over developmental times, were investigated. In addition, the sequences of rDNA regions and β-tubulin genes were determined. The result clearly demonstrated that the trophocyte at 36 h was covered with 4 layers, and then outer layer of the sporocyte gradually degraded over time, resulting in wall structure consisting of two layers, with even processes being detached from 7-day-old sporangium with smooth surface, indicating that the difference in the number of layers seems not to be an appropriate ultrastructural character for distinguishing P. infectans and P. sinerae. While pairwise comparison of the large subunit rDNA sequences showed 100% identity among P. infectans / P. sinerae species complex, genetic differences were found in the small subunit (SSU) rDNA sequences but the differences were relatively small (11-13 nucleotides) compared with those (190-272 nucleotides) found among the rest of Parvilucifera species (P. rostrata and P. corolla). Those small differences in SSU rDNA sequences of P. infectans / P. sinerae species complex may reflect the variations within inter- strains of the same species from different geographical areas. Taken together, all morphological, ultrastructural, and molecular data from the present study suggest that they are the same species.