• Animal Systematics, Evolution and Diversity
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• 제22권1호
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• pp.29-35
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• 2006

Two ciliates of suborder Euplotina collected from the two habitats (estuarine littoral and sewage treatment plant) in Ulsan, Korea were Euplotes charon ($M\ddot{u}ller$, 1773) and Diophrys oligothrix Borror, 1965. These two species are reported for the first time from Korea. The description was based on the observation of living and silver impregnated specimens. Diagnostic characteristics of these species are as follows. E. charon: size in vivo about $90-130\times65-80{\mu}m$, adoral zone of membranelles over 79.5% of cell length with 54-80 adoral membranelles; right margin of the peristome shaped sinusoidal form and passed through adoral zone of membranelles; buccal cavity wide anteriorly; 10 frontoventral, 5 transverse, 4 caudal cirri, 12 dorsal kineties, mid-dorsal kinety with 21 -25 dorsal bristles; silver-line system double-eurystomus type. D. oligothrix: size in vivo about $80-90\times30-70{\mu}m$; body shape ovoid with prominent right concave posterio-lateral end, two irregular elongated macronuclei with one micronucleus, respectively; 7 fronto-ventral, 5 transverse, 2 left marginal and 2 caudal cirri, 4 dorsal kineties with prominent bristles about $9-14{\mu}m$ long in vivo.

• Animal Systematics, Evolution and Diversity
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• 제22권2호
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• pp.223-229
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• 2006

Two litonotid ciliates collected from the freshwater habitats in Korea were identified as Loxophyllum meleagris ($M\ddot{u}ller$, 1773) and Siroloxophyllum utriculariae (Penard, 1922). The description was based on the observation of living and protargol impregnated specimens, and biometric analysis. Their diagnostic characteristics are as follows. L. meleagris; $163-480\times80-100{\mu}m$ in vivo, body shape lancet or knife-like; dorsal margin with 10-19 extrusome warts; 8-35 macronuclei nodules, like a string of bead; 16-21 somatic kineties on right side (including perioral kinety 2, 3) and 6-11 on left side (including perioral kinety 1); 1 contractile vacuole located at posterior part at diastole stage, extending along the dorsal margin toward anterior end with a single long narrow canal. S. utriculariae; $110-170\times78-150{\mu}m$ in vivo, body shape lancet like; dorsal margin without extrusome warts; 2 macronuclei, spherical; 12-19 somatic kineties on right side, 3-7 on left side (including perioral kinety 1); 2-3 contractile vacuoles, first one located anterior ventrally, second one located posterior dorsally and last one located near posterior end of cell.

• Journal of Species Research
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• 제12권spc2호
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• pp.23-32
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• 2023

During screening for indigenous prokaryotic species in Republic of Korea in 2021, a total of 21 bacterial strains assigned to the phylum Bacteroidota were isolated from a variety of environmental habitats including pine cone, seaweed, soil, sea sediment, brackish water and moss. Based on the 16S rRNA gene sequence similarity value of more than 98.7% and formation of a robust phylogenetic clade with the type strain of the closest bacterial species, it was found that the 21 strains belong to independent and recognized bacterial species. There has been no official report that the identified 21 species have been isolated in Republic of Korea up to date. Therefore, 16 species in six genera of two families in the order Flavobacteriales, two species in two genera of two families in the order Cytophagales, one species in one genus of one family in the order Chitinophagales and two species in one genus of one family in the order Sphingobacteriales are proposed as unrecorded species of the phylum Bacteroidota isolated in Republic of Korea. Their Gram reaction, colony and cell morphology, basic phenotypic characteristics, isolation source, taxonomic status, strain ID and other information are described in the species descriptions.

• Animal Systematics, Evolution and Diversity
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• 제40권2호
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• pp.130-134
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• 2024

The family Velutinidae is found in various intertidal and subtidal habitats worldwide including Arctic and Antarctic seas. They are characterized by possessing a fragile shell that is partially or entirely covered by the mantle. Eight valid species of the genus Coriocella have been reported mostly in the Indo-West Pacific. Here we report Coriocella jayi Wellens, 1996 from Korean waters for the first time and describe details of their external morphology and radula characteristics using scanning electron microscopy, and provide the mtDNA cox1 sequence as a DNA barcode sequence information. This species is distinguished from other congeneric species by having six cylinder-shaped tubercular lobes of their dorsal part of mantle body and mantle color. Phylogenetic tree using the mtDNA cox1 sequence data shows that two Coriocella species (C. jayi and C. nigra) are grouped as their respective sister among Velutinidae species, and these relationships are strongly supported by 100% bootstrap value. Despite the morphological similarities, further investigation will be needed to confirm whether the African and Korean populations can be justified as the same species with a disconnected distribution range, or represent morphologically similar but two distinct species.

• The Plant Pathology Journal
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• 제40권3호
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• pp.251-260
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• 2024

Flavobacterium is a genus within the phylum Bacteroidota that remains relatively unexplored. Recent analyses of plant microbiota have identified the phylum Bacteroidota as a major bacterial group in the plant rhizosphere. While Flavobacterium species within the phylum Bacteroidota have been recognized as pathogens in the aquatic habitats, microbiome analysis and the characterization of novel Flavobacterium species have indicated the great diversity and potential of their presence in various environments. Many Flavobacterium species have positively contribute to plant health and development, including growth promotion, disease control, and tolerance to abiotic stress. Despite the well-described beneficial interactions of the Flavobacterium species with plants, the molecular mechanisms and bacterial determinants underlying these interactions remain unclear. To broaden our understanding of the genus Flavobacterium's role in plant health, we review the recent studies focusing on their ecological niche, functional roles, and determinants in plant-beneficial interactions. Additionally, this review discusses putative mechanisms explaining the interactions between plants and Flavobacterium. We have also introduced the importance of future research on Flavobacterium spp. and its potential applications in agriculture.

• 환경생물
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• 제41권4호
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• pp.570-607
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• 2023

The subgenus Tricoma Cobb, 1894 comprises free-living marine nematodes encompassing a total of 83 validated taxa. Within this diversity, twenty-one taxa thrive in the deep sea, while twenty-three are found in coral reefs, flat areas, or green algae. Additionally, eleven taxa inhabit the sublittoral zone at depths exceeding 10 meters, and the remaining taxa are situated on beaches, coasts, or in habitats lacking detailed information. In the course of a survey focused on the East Sea free-living marine nematodes, we identified four new and two previously unrecorded species belonging to the subgenus Tricoma. Specifically, two new species, Tricoma (Tricoma) breviseta sp. nov. and T. (T.) donghaensis sp. nov., were discovered in mud-sandy sediment in deepsea environments below 2000 meters within the Ulleung Basin and Hupo Bank. Two previously unrecorded species [T. (T.) paralucida Decraemer, 1987 and T. (T.) similis Cobb, 1912] and the two newly found species [T. (T.) longicauda sp. nov. and T. (T.) ulleungensis sp. nov.] were obtained from subtidal coarse sand at a depth of 20 meters during a survey of the waters surrounding Ulleungdo Island. The distribution and information on validated taxa within the subgenus Tricoma were systematically collected, reviewed, and cataloged. Detailed morphological features and illustrations of Tricoma species from Korea were provided through the use of differential interference contrast microscopy.

• Animal Systematics, Evolution and Diversity
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• 제40권3호
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• pp.211-220
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• 2024

During the surveys of ciliates from hypoxic habitats, three marine anaerobic species were found: Metopus spiculatus, M. vestitus, and Muranothrix felix. These species have not been previously recorded in South Korea and belong to the taxonomic classes Armophorea and Muranotrichea. The morphology of these species was examined by both microscopic observations of live specimens, and stained cells using protargol impregnations. Metopus spiculatus has the following characteristics: body size 80-110×25-35 ㎛ in vivo, beak-like structure at the end of preoral dome, ectosymbiotic bacteria covering cell surface, intracytoplasmic needle-shaped structures and the conspicuous tail end. Metopus vestitus has the following distinguishing characteristics: body size 95-130×25-45 ㎛ in vivo, a cone-shaped body, a covering of ectosymbiotic bacteria on its cell surface, intracytoplasmic needleshaped structures, somatic kineties arranged in 26-28 longitudinal rows, and a posterior part tapered into a tail. Muranothrix felix has the following characteristics: body size 100-130×20-30 ㎛ in vivo, elongated body with twisted neck region, bristle-like cilia protruding perpendicular to the cell margin, ectosymbiotic bacteria covering the cell surface, about 10 macronuclear nodules, and a long, stiffened caudal cilium.

• Journal of Species Research
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• 제13권3호
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• pp.332-339
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• 2024

The filamentous freshwater red alga Compsopogon caeruleus(Compsopogonophyceae, Compsopogonaceae, Rhodophyta) occurs in tropical and subtropical regions of worldwide. This species has been reported from Asia, America, Africa, Europe and Oceania, and the worldwide distribution of Compsopogon caeruleus is in variable water habitats. Several morphospecies of the genus Compsopogon had been recorded, but recent molecular phylogenetic analyses with worldwide sampling identified a monospecific genus, C. caeruleus. In the present study, we first report a freshwater red alga Compsopogon caeruleus from Korea. We identified Compsopogon caeruleus in an urban river in Yongin City, and analyzed its morphological and genetic characteristics. Nuclear 18S rDNA, plastidal rbcL gene and mitochondrial cox1 gene sequences isolated from Korean Compsopogon caeruleus showed high sequences similarity with Compsopogon caeruleus from worldwide (98.6-100% (18S rDNA), 99-100% (rbcL) and 97.7-100% (cox1)). These sequences similarities support the identification of a red alga found in Korea as Compsopogon caeruleus. This new geographical report provides the useful information for understanding the distribution and habitat range of Compsopogon caeruleus especially concerning urban freshwater environments.

• Animal Systematics, Evolution and Diversity
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• 제11권1호
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• pp.39-64
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• 1995

진도의 담수산 물벼룩류 및 요각류의 종류상, 서식처별 종조성, 물벼룩류와 요각류의 출현특성 및 상관출현성 등을 조사하기 위해 , 1994년 7월 23-25일과 11월 1-3의 두차례에 걸쳐 저수지, 하천, 습지, 논 , 농수로 , 연못 , 샘 등 다양한 담수 서식처 35개 지소에서 물벼룩류와 요각류을 채집하였다. 조사결과 5종의 미동정종을 포함한 2목 6과 17속 27종의 물벼룩류와 3종의 미동정종을 포함한 3목 6과 21 속 28종의 요각류가 본 조사기간 동안 출현하였는데 , 이 가운데 물벼룩류 Daphnia obtusa Kurz 와 요각류 Elaphoidella bidens (Schmeil)는 한국미기록종이다. 정수역의 저수지에서는 7월에 물벼룩류 Diaphanosoma sp. 와 요각류인 온난검물벼룩(Thermocyclops taihokuensis)이 , 11월에는 긴뿔물벼룩(Bosmina longirostris)과 참검물벼룩(Cyclops vicinus vicinus)이 각각 우점하였고 , 저수지의 가장자리 부식질이 많은 곳과 웅덩이에서는 긴눈시모물벼룩(Simocephalus vetulus)과 사각배큰씨물벼룩(Alona rectangula), 둥근씨물벼룩(Chydorus sphaericus)등의 물벼룩류와 톱니꼬리검물벼룩(Eucyclops serrulatus)을 비롯한 꼬마검물벼룩(Microcyclops varicans), 갈고리보통검물벼룩(Mescocylops pepheiensis)등의 요각류가 출현하였다. 7월에서 11월로 가면서 Diaphanosoma sp. 와 온난검물벼룩(T.taihokuensis)의 개체수는 격감하였고 대신 긴뿔물벼룩과 유리온난검물벼룩(T.crassus)의 개체수와 출현비도는 증가하였다. 연못에서는 7월에 온난검물벼룩, 11월에는 시궁모이나물벼룩(Miina weismanni)이 우점하였다. 논에서는 모이나물벼룩(Moina macrocopa) 과 온난검물벼룩(T.taihokuensis)이 우점하였다. 유수역의 계류 및 샘에서는 물벼룩류 Alona sp.와 하르팍티쿠스류 두마디털보장수노벌레(Attehyella byblis) , 네가시털보장수노벌레(A.tetraspinosa) 등이 출현하였다. 하천에서는 물벼룩류의 출현빈도가 낮았으며, 7월에 비해 11월에 물벼룩 출현종들이 다양한 편이었는데, 부유성 종에서는 긴뿔물벼룩과 저서성 종에서는 둥근씨물벼룩이 가장 흔한 종이었다. 욕가류는 하부의 하구를 제외하고는 대부분의 하천의 조사지점에서 거의 같은 종조성을 나타냈는데 , 톱니꼬리검물벼룩(e.serrulatus)과 갈고리보통검물벼룩(M.phieiensis)이 가장 흔하고 개체수가 많은 종이었다. 물벼룩류와 요각류의 상관출현성에서는 , 정수역의 경우 물벼룩류 Diaphanosoma sp. 와 온난검물벼룩의 2 종, 긴뿔물벼룩, 둥근씨물벼룩, 사각배튼씨물벼룩 및 톱니꼬리검물벼룩의 4종, 짧은배씨물벼욱(Disparalona rostrata)과 유리온난 검물벼룩, 꼬마검물벼욱, 갈고리보통검물벼룩의 4종, 시모긴눈물벼욱, 시궁모이나 물벼룩, 긴뿔물벼룩붙이(Bosminopsis detersi) , 줄무늬큰씨물벼욱 (Alona costata)과 마루딱정장수노벌레(Canthocamptus carinatus) 및 참검물벼욱의 6종등이 각각 종의 출현에서 다른 종들에 비해 서로 깊은 상관성이 잇는 것으로 드러났다. 유수역에서는 긴눈시모물벼룩과 갈고리보통검물벼룩의 2종, 시궁모이나물벼룩과 긴뿔물벼룩, 긴뿔물벼룩붙이와 마루딱정장수노벌레의 4종등이 각각 시기나 장소에 따른 종의 출현성에서 다른 종들에 비해 서로 밀접한 관계에 있는 것으로 나타났다.

• 미생물학회지
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• 제49권2호
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• pp.156-164
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• 2013

방선균은 의약, 농업 및 식품 생산 등에 유용하게 사용되는 이차대사물질을 생산하는 미생물 자원으로 자연환경 내에서 많은 생물들과 긴밀한 상호작용을 유지하고 있다. 본 연구에서는 장수풍뎅이 유충의 분변에 존재하는 방선균의 다양성과 기능성을 조사하기 위해서 비배양적 접근과 배양적 방법으로 실험을 수행하였다. 먼저 시료로부터 직접 추출한 community DNA에서 방선균-특이 primer를 이용하여 방선균의 16S rRNA 유전자를 PCR로 증폭, 클로닝한 후에 각 clone에 삽입된 염기서열을 분석하였다. 총 37개의 염기서열을 얻었으며 계통분류학적 분석을 수행한 결과, 15속 24종으로 분류되었다. 아울러 53개의 방선균 균주를 장수풍뎅이 유충 분변으로부터 분리하였다. 형태학적 특징을 비교하여 최종적으로 27개의 균주를 선발하여 다양성, 항균활성 및 생화학적 특징을 검정하였다. 분리된 균주들은 4속 14종으로 분류되었으며, 24균주(89%)는 Streptomyces 속으로 분류되었다. 대다수의 균주들이 식물병원성 곰팡이와 그람양성 세균에 대해 길항 효과를 보였다. 또한 많은 균주들이 셀룰로오스와 카제인을 분해하는 생화학적 특징을 보였다. 본 연구를 통해, 장수풍뎅이 유충의 분변 시료로부터 다양한 방선균이 분리될 수 있으며, 분리된 균주들은 다양한 항균효과 및 효소활성을 지니고 있다는 것을 확인하였다. 결론적으로 본 연구는 장수풍뎅이와 같은 곤충의 장과 분변은 다양한 방선균의 서식처이며, 이곳에서 유용한 생리활성 물질을 발견할 수 있다는 것을 제시한다.