통영산 물렁증 멍게 피막의 편모충 감염

신윤경 ( Yun Kyung Shin ),김현중 ( Hyoun Joong Kim ),박경일 ( Kyung Il Park ),최민순 ( Min Soon Choi ),전제천 ( Je Cheon Jun ),김응오 ( Eung Oh Kim ) 한국어병학회 2011 한국어병학회지 Vol.24 No.3

The edible ascidian Halocynthia roretzi is a commercially important fisheries resource in Korea. However, for the last several years, outbreaks of mass mortalities of the species have been occurring along the south and east coasts of Korea, where most ascidians are produced. Although it is known that tunic-softness syndrome is associated with these mortality events, the agent causing the syndrome has not yet been confirmed. To determine the agent causing tunic-softness syndrome, healthy and diseased ascidians were collected in March 2011 from Tongyeong, on the south coast of Korea, and were used for biological and pathological investigations. The results showed that diseased ascidians exhibited remarkably reduced body fluid, fatness index, and tunic index compared with healthy specimens. Interestingly, bi-flagellated protozoans were observed specifically in the tissue imprints and tunic cultures of diseased ascidians at an occurrence rate of 97.5%. Histological observation showed that the thickness of the tunics of diseased ascidians was reduced by half, and irregular structure and breakdown of the tunic fiber bundles were observed. In particular, flagellate-like cells were observed in the diseased ascidians. Our study clearly shows that bi-flagellated protists are present only in the softened ascidians, suggesting that the flagellates are partly or entirely associated with soft-tunic syndrome. Accordingly, further investigations to verify the effects of the flagellates found in the present study on soft-tunic syndrome should be conducted.

강화도 펄 갯벌에서 저서성 원생동물 분포의 시간적 변이와 박테리아 및 미세 조류에 대한 포식압

양은진,최중기,유만호,조병철,최동한,Yang, Eun-Jin,Choi, Joong-Ki,Yoo, Man-Ho,Cho, Byung-Cheol,Choi, Dong-Man 한국해양학회 2005 바다 Vol.10 No.1

강화도 장화리의 펄 갯벌에 서식하는 저서 원생동물 군집의 계절 분포 및 섭식률을 파악하기 위하여 2002년 4월부터 2004년 4월까지 총 3개의 정점을 선정하여 2-3개월 간격으로 조사를 수행하였다. 저서 원생동물의 현존량과 생물량은 섬모충류와 종속영양 편모류에 의해 98% 이상 우점하여 나타났으며, 그 외 종속영양 와편모류와 아메바 그룹이 일부 시기에 관찰되었으나 중요하지 않은 그룹으로 나타났다. 종속영양 편모류의 현존량과 탄소량은 각각 $0.2-5.9{\times}10^5\;cells\;cm^{-3}$와 $0.02-9.2\;{\mu}C\;cm^{-3}$로 분포하였으며, 생물량은 춘계와 추계에 비교적 높은 분포를 보였다. 종속영양 편모류는 표충 2.5 mm 이내에서 다른 층에 비해 높은 분포를 보였으며, 종속영양 편모류의 수평적 분포는 정점별로 차이가 없는 것으로 나타났다. 종속영양 편모류는 $10{\mu}m$이하의 크기에 의하여 주로 우점하여 나타났으나, 2월과 4월 사이에 $20{\mu}m$ 이상의 종속영양 유글레나가 높게 출현하였다 섬모충류의 현존량과 생물량은 각각 $0.1-17.8{\times}10^3\;cells\;cm^{-3}$와 $0.02-9.1\;{\mu}gC\;cm^{-3}$ 범위로 분포하였으며 춘계와 추계에 높은 분포를 보였다. 섬모충류 그룹은 주로 하모류에 의해 우점 하였으며, 계절별로 두드러진 우점 종들은 관찰되지 않았다. 섬모충류의 수직적 분포는 표층 2.5 mm이내에서 높은 분포를 보였으며, 정점별 분포는 조간대 상부 정점에 비해 조간대 하부 정점에서 높은 분포를 보였다. 섬모충류의 시.공간적 분포는 저서 미세조류의 생물량 분포와 유사한 양상을 보였다. 조사기간동안 저서 원생동물 그룹의 탄소량은 섬모충류에 의해 평균 66%의 높은 우점률을 보였으며, 저서 원생동물의 계절변동은 저서 미세조류의 변동과 유사한 양상을 보였다. 본 연구에서 저서 원생동물의 섭식률을 측정한 결과 박테리아 생산력과 저서 미세조류 생산력의 각각 13.4-40.7%와 20.1-36.4%를 제거하였으며, 박테리아에 대한 섭식률은 섬모충류에 비해 종속영양 편모류에 의해 더 높은 것으로 나타났다. 박테리아와 돌말류에 대한 저서 원생동물의 섭식률은 춘계에 가장 높았으며 저서 미세생물 먹이 망에서 저서 원생동물은 미세생물 군집의 생물량이 높은 춘계에 박테리아와 돌말류의 포식자로서 중요한 역할을 하고 있음을 시사하였다. To investigate the seasonal distribution and grazing impacts of benthic protozoa in mud flat, their abundance, biomass and grazing rates of benthic protozoa were evaluated at interval of two or three month in Gangwha Island from April, 2002 to April, 2004. Heterotrophic flagellates and ciliates accounted for an average 98% of benthic protozoa biomass. Abundance and carbon biomass of heterotrophic flagellates ranged from $0.2{\times}10^5$ to $5.9{\times}10^5\;cells\;cm{-3}$ and from 0.02 to $9.2\;{\mu}gC\;cm^{-3}$, respectively. Biomass of heterotrophic flagellates was high in spring and fall, and showed no differences among stations. Abundance and biomass of heterotrophic flagellates decreased with the depth and were high within the surface 2.5 m sediment layer. The majority of heterotrophic flagellates were less than $10\;{\mu}m$ in length, and few euglenoid flagellates were larger than $20\;{\mu}m$. Abundance and carbon biomass of ciliates ranged from $0.1{\times}10^3$ to $17.8{\times}10^3\;cells\;cm^{-3}$ and from 0.02 to $9.1\;{\mu}gC\;cm^{-3}$, respectively, and those of ciliates were high in spring and fall. Biomass of ciliates was high within the surface 2.5 mm sediment layer and was higher at st. J2 and st. J3 than st. J1. Among the revealed benthic ciliates, the hypotrichs were the most important group in terms of abundance and biomass. During the sampling periods, an average 66% of benthic protozoa biomass was covered by ciliates. The seasonal distribution of benthic protozoa showed an almost similar fluctuation pattern to that of chlorophyll-a. The results suggest that the biomass of benthic protozoa were mainly controlled by prey abundance, for example, diatoms. Based on ingestion rates, benthic protozoa removed from 13.4 to 40.7% of bacterial production and from 20.1 to 36.4% of primary production. Ingestion rates of benthic protozoa on bacteria and microphytobenthos were high in April. Benthic protozoa in this study area may play a pivotal role in the carbon flow of the benthic microbial food web during spring.

Some Free-Living Heterotrophic Flagellates from Marine Sediments of Tropical Australia

Lee, Won-Je The Korean Society of Oceanography 2006 Ocean science journal Vol.41 No.2

The diversity of heterotrophic flagellates was examined at marine sediments around Cape Tribulation, Australia. The species described belong to the Alveolates, Apusomonadiae, Cercomonadida, Choanoflagellida, Cryptomonadida, Diplomonadida, Euglenozoa incertae sedis, Kathablepharidae, Kinetoplastida, Pedinellids, Stephanopogonidae, Stramenopiles, Stramenopiles incertae sedis, Thaumatomonadidae and Protista incertae sedis. Among the 51 species from 38 genera encountered in this study is one new taxon: Glissandra similis n. sp., and two new names are introduced: Goniomonas abrupta (Skvortzov 1924) nomen nodum and Cercomonas skvortzovi (Skvortzov 1977) nomen nodum. There was little evidence for endemism because most flagellates including one new taxon described here have been reported.

Three Newly Recorded Marine Heterotrophic Flagellates (Protist), Neometanema parovale, Stephanopogon pattersoni and Thaumatomastix sp. from South Korea

Lee, Won Je Korean Society of Environmental Biology 2015 환경생물 : 환경생물학회지 Vol.33 No.2

Three marine heterotrophic flagellates from intertidal sediments of Gwang-Am beach and Garorim Bay, Korea were identified as Neometanema parovale Lee and Patterson 2014, Stephanopogon pattersoni Lee et al. 2014 and Thaumatomastix sp. These species are reported taxonomically for the first time from Korea, and are described with illustrations and micrographs. Diagnostics of these species are as follows. Neometanema parovale (Euglenozoa): size in vivo, $10{\sim}23{\mu}m\;long$ with 22 pellicular strips, ingestion apparatus barely visible by light microscopy and two flagella pointed in different directions when moving. Stephanopogon pattersoni (Percolozoa): size in vivo, $20{\sim}33{\mu}m\;long$, with 6 ventral and 1 ventro-lateral ciliary rows, and three barbs. Thaumatomastix sp. (Cercozoa): size in vivo, $14{\sim}17{\mu}m$ with body scales and spines, and two flagella with one naked and one scaled.

Three Newly Recorded Marine Heterotrophic Flagellates (Protist), Neometanema parovale, Stephanopogon pattersoni and Thaumatomastix sp. from South Korea

이원제 한국환경생물학회 2015 환경생물 : 환경생물학회지 Vol.33 No.2

Three marine heterotrophic flagellates from intertidal sediments of Gwang-Am beach and Garorim Bay, Korea were identified as Neometanema parovale Lee and Patterson 2014, Stephanopogon pattersoni Lee et al. 2014 and Thaumatomastix sp. These species are reported taxonomically for the first time from Korea, and are described with illustrations and micrographs. Diagnostics of these species are as follows. Neometanema parovale (Euglenozoa): size in vivo, 10~23 μm long with 22 pellicular strips, ingestion apparatus barely visible by light microscopy and two flagella pointed in different directions when moving. Stephanopogon pattersoni (Percolozoa): size in vivo, 20~33 μm long, with 6 ventral and 1 ventro-lateral ciliary rows, and three barbs. Thaumatomastix sp. (Cercozoa): size in vivo, 14~17 μm with body scales and spines, and two flagella with one naked and one scaled.

Three Newly Recorded Marine Heterotrophic Flagellates (Protist), Neometanema parovale, Stephanopogon pattersoni and Thaumatomastix sp. from South Korea

Won Je Lee 한국환경생물학회 2015 환경생물 : 환경생물학회지 Vol.33 No.2

Three marine heterotrophic flagellates from intertidal sediments of Gwang-Am beach and Garorim Bay, Korea were identified as Neometanema parovale Lee and Patterson 2014, Stephanopogon pattersoni Lee et al. 2014 and Thaumatomastix sp. These species are reported taxonomically for the first time from Korea, and are described with illustrations and micrographs. Diagnostics of these species are as follows. Neometanema parovale (Euglenozoa): size in vivo, 10~23 μm long with 22 pellicular strips, ingestion apparatus barely visible by light microscopy and two flagella pointed in different directions when moving. Stephanopogon pattersoni (Percolozoa): size in vivo, 20~33 μm long, with 6 ventral and 1 ventro-lateral ciliary rows, and three barbs. Thaumatomastix sp. (Cercozoa): size in vivo, 14~17 μm with body scales and spines, and two flagella with one naked and one scaled.

Light affects picocyanobacterial grazing and growth response of the mixotrophic flagellate Poterioochromonas malhamensis

Thomas Weisse,Michael Moser 한국미생물학회 2020 The journal of microbiology Vol.58 No.4

We measured the grazing and growth response of the mixotrophic chrysomonad flagellate Poterioochromonas malhamensis on four closely related picocyanobacterial strains isolated from subalpine lakes in central Europe. The picocyanobacteria represented different pigment types (phycoerythrin- rich, PE, and phycocyanin-rich, PC) and phylogenetic clusters. The grazing experiments were conducted with laboratory cultures acclimated to 10 μmol photon/m2/sec (low light, LL) and 100 μmol photon/m2/sec (moderate light, ML), either in the dark or at four different irradiances ranging from low (6 μmol photon/m2/sec) to high (1,500 μmol photon/m2/ sec) light intensity. Poterioochromonas malhamensis preferred the larger, green PC-rich picocyanobacteria to the smaller, red PE-rich picocyanobacterial, and heterotrophic bacteria. The feeding and growth rates of P. malhamensis were sensitive to the actual light conditions during the experiments; the flagellate performed relatively better in the dark and at LL conditions than at high light intensity. In summary, our results found strain-specific ingestion and growth rates of the flagellate; an effect of the preculturing conditions, and, unexpectedly, a direct adverse effect of high light levels. We conclude that this flagellate may avoid exposure to high surface light intensities commonly encountered in temperate lakes during the summer.

First records of nine free-living heterotrophic flagellates from South Korea

Lee, Won Je The National Institute of Biological Resources 2020 Journal of species research Vol.9 No.4

Nine free-living heterotrophic flagellates were cultured from marine intertidal sediments and freshwater sediments from Korea. These species are described with uninterpreted records based on light microscopy of living cells and reported taxonomically for the first time from Korea. Diagnostics of these species are as follows; Notosolenus hemicircularis: 9-11.8 ㎛ long with flagellar reservoir, ventrally flattened and dorsally convex with hyaline semicircular collar around short anterior neck, and 8 ridges on cell surface. Thecamonas tranhens: 4.5-7.1 ㎛ long, plastic with proboscis comprising an anterior flagellum surrounded by membranous sleeve. Bodomorpha minima: 4.5-7.0 ㎛ long, rigid with small rostrum in anterior end and active anterior flagellum. Cercomonas hiberna: 5.6-10.9 ㎛ long, very plastic with pseudopodia, cytoplasmic strand and 1 or 2 contractile vacuoles. Cercomonas pellucida: 7.5-13 ㎛ long, plastic with pseudopodia, cytoplasmic strand and single contractile vacuole. With nucleus closely connected to basal bodies. Eocercomonas echina: 4.7-6.5 ㎛ long, plastic with pseudopodia, cytoplasmic strand and 1 or 2 contractile vacuoles. Paracercomonas astra: 5.7-7.3 ㎛ long, moderately metabolic with pseudopodia, cytoplasmic strand and 1 or 2 contractile vacuoles. Paracercomonas minima: 5-9 ㎛ long, metabolic with pseudopodia, cytoplasmic strand and single contractile vacuole. Paracercomonas producta: 6.1-9.9 ㎛ long, very metabolic with pseudopodia, long cytoplasmic strand and single contractile vacuole.

연구논문 : 옥계만 단일정점에서 극미소 및 미소플랑크톤의 시간적 분포

이원제 ( Won Je Lee ) 한국환경과학회 2007 한국환경과학회지 Vol.16 No.7

Heterotrophic Euglenids from Marine Sediments of Cape Tribulation, Tropical Australia

Lee, Won-Je The Korean Society of Oceanography 2006 Ocean science journal Vol.41 No.2

This paper presents new data on free-living heterotrophic euglenids (Euglenozoa, Protista) that occurred in the marine sediments at Cape Tribulation, Queensland, Australia. Twenty-nine species from 9 genera are described with uninterpreted records based on light microscopy, including one new taxon: Notosolenus capetribulationi n. sp. There was little evidence for endemism because the majority of heterotrophic euglenid species encountered here have been reported or were found from other habitats.