• ALGAE
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• 제34권4호
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• pp.277-288
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• 2019

Freshwater red algae of the order Batrachospermales are poorly studied in India and Nepal, especially on a molecular basis. During a survey in northeast India and east Nepal, six populations of the genus Sheathia were found and analyzed using molecular and morphological evidence. Phylogenetic analyses based on the rbcL gene sequences grouped all populations in a large clade including our S. arcuata specimens and others from several regions. Sheathia arcuata represents a species complex with a high sequence divergence and several smaller clades. Samples from India and Nepal were grouped in three distinct clades with high support and representing new cryptic species: a clade formed by two samples from India, which was named Sheathia assamica sp. nov.; one sample from India and one from Nepal formed another clade, named Sheathia indonepalensis sp. nov.; two samples from Nepal grouped with sequences from Hawaii and Indonesia (only 'Chantransia' stages) and gametophytes from Taiwan, named Sheathia dispersa sp. nov. Morphological characters of the specimens from these three species overlap one another and with the general circumscription of S. arcuata, which lacks the heterocortication (presence of bulbous cells in the cortical filaments) present in other species of the genus Sheathia. Although the region sampled is relatively restricted, the genetic diversity among specimens of these three groups was high and not closely related in the phylogenetic relationship with the other clades of S. arcuata. These data corroborate information from other groups of organisms (e.g., land and aquatic plants) that indicates this region (Eastern Himalaya) as a hotspot of biodiversity.

• Parasites, Hosts and Diseases
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• 제55권1호
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• pp.39-45
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• 2017

The present study was performed to reveal the morphological characteristics and molecular phylogenetic position of Platynosomum fastosum Kossack, 1910. A total 167 specimens of P. fastosum were collected in 8 (4.9%) out of 163 sets of gall-bladders and bile ducts of cats. The number of worms was 1-105 per infected cat. This species was characterized by having a long and slender body, slightly larger ventral sucker than the oral sucker, indistinct prepharynx, small pharynx, short esophagus, bifurcation midway between 2 suckers, and ceca extending to the posterior end of the body. The length of the partial sequences of ITS1 and 5.8S rDNA of P. fastosum were 990 bp, GC-rich. AT/GC ratio was 0.9, there were 9 polymorphic sites, and intraspecific variations ranged from 0.1% to 0.9%. Phylogenetic analyses by neighbor-joining phylogram inferred from ITS1 rDNA sequences revealed that the genetic distance between P. fastosum specimens ranged from 0.3 to 1.5% while the smallest interspecific distance among dicrocoeliid species was 20.9 %. The redescription and genetic characters of P. fastosum are taxonomically important to recognize future different species of the genus Platynosomum showing high intraspecific and morphological variability.

• 한국어류학회지
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• 제21권4호
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• pp.291-298
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• 2009

한국, 중국, 일본, 대만 등 동아시아에 분포하는 피라미속 (Zacco) 어류에 대한 mitochondrial cytochrome b gene의 염기서열 분석을 통해 분자계통학적 유연관계를 조사하였다. MP tree 분석 결과, 한국산 참갈겨니와 갈겨니 집단은 모두 단계통군을 형성하고 있었으나 생물분포구계의 남한아 지역에 분포하는 참갈겨니와 갈겨니 집단은 일본산 갈겨니와 유전적으로 유사하게 분석되었다. 또한 한국산 피라미 집단은 일본산 피라미와 유전적 친화성을 보였으나, 중국산 피라미는 끄리와 분자계통학적 유연관계를 형성하였다. 참갈겨니의 한강집단은 동해 중북부에 서식하는 집단과 유전적으로 유사하였고, 갈겨니의 동진강과 영산강 집단은 유전적 동일 집단, 동진강과 섬진강 집단은 유전적 유사집단으로 여겨졌다. NJ tree 분석을 통해 피라미 집단은 참갈겨니와 갈겨니 및 Z. sieboldii 집단과는 오래전에 공동조상으로부터 분화되었고, Z. sieboldii의 조상으로부터 참갈겨니와 갈겨니가 분기진화한 것으로 추정되었다. 또한 중국에 서식하는 피라미는 한국산 피라미 집단과 상당한 유전적 차이를 보였을 뿐만 아니라 끄리속 어류와 분자계통수를 형성하고 있어 추후 동물지리학적 분포 및 피라미속 어류에 대한 계통분류학적 논의가 요구된다.

• 생명과학회지
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• 제27권10호
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• pp.1152-1160
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• 2017

단세포 녹조류 균주를 경상북도 울릉군 울릉도 거북바위 주변 조수웅덩이로부터 순수분리하여 형태적, 분자적, 및 생화학적 특성을 분석한 결과 옥세노클로렐라 프로토테코이드에 속하는 것으로 밝혀졌다. 본 종은 현재까지 한국에서 공식 기록이 없는 미기록종으로 옥세노클로렐라 프로토테코이드 MM0011 균주라고 명명하였으며, 생장, 지질/광합성 색소 조성 및 바이오매스 특성에 대해 조사를 실시하였다. 분리균주는 광범위한 온도($5-35^{\circ}C$)에서 생장할 수 있었으며 1.5 M 염화나트륨 농도까지 생존할 수 있었다. 가스크로마토그래프/질량분석기를 이용한 분석 결과, 본 균주에는 영양적으로 중요한 불포화지방산이 풍부한 것으로 나타났으며, 특히 리놀네산(27.6%) 및 알파 리놀렌산(37.2%)이 주요 지방산 성분으로 확인되었다. 따라서 본 토착 미세조류 균주는 어유 또는 식물성유를 대체할 수 있는 잠재적인 오메가-3 및 오메가-6 불포화지방산 원료가 될 수 있을 것으로 사료된다. 또한, 고부가가치 항산화 물질인 루테인이 보조색소로서 본 균주에 의해 생합성 되는 것으로 밝혀졌다. 일반성분분석 결과 MM0011 균주의 휘발성물질 함량은 85.6%였으며, 원소분석 결과 총 발열량은 $20.3MJ\;kg^{-1}$으로 나타났다. 또한 배지로부터 40.5%의 전질소와 27.9%의 전인을 각각 제거할 수 있어 향후 바이오연료 원료물질 생산과 오 폐수처리를 연계할 수 있는 가능성 역시 제시하였다. 추가적으로 MM0011 바이오매스는 높은 단백질 함량(51.4%)을 갖고 있어 우수한 동물사료의 원료가 될 수 있는 가능성도 보여주고 있다. 따라서, 본 균주는 미세조류 기반 생화학 물질 생산 및 바이오매스 원료로서 상업적인 이용 가능성이 높음을 시사한다.

• Animal cells and systems
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• 제8권3호
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• pp.231-233
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• 2004

Sequences of cytochrome b gene and control region of mitochondrial DNA from Korean common otters (Lutra lutra lutra L.) were examined to provide the genetic information for the conservation of this subspecies. Two haplotypes and one haplotype were revealed in cytochrome b gene and control region, respectively. The available sequences of European common otter (L. l. lutra) from GenBank were compared together with those of Korean common otter in order to determine the degree of sequence variation between them. In cytochrome b gene sequences, two haplotypes from Korea and two haplotypes of Europe showed differences in 12 of 1,045 sites. The Tamura-Nei nucleotide distances between two European haplotypes was 0.10% and those between two Korean haplotypes was also 0.10%, but those between Korean haplotypes and European ones ranged from 0.96% to 1.16%. In the control region, one Korean haplotype and seven European ones showed differences in seven of 300 sites; the Tamura-Nei distances among seven European haplotypes were 0.34% to 1.01%, but those between Korean haplotype and European ones ranged from 1.01% to 1.69%. Although further molecular and morphological studies with specimens from eastern Asia including Amur region and northeast China are needed, it is possible that the Korean common otter might be closer or identical to the far-eastern Asian common otter, L. l. amurensis Dybowski.

• 생명과학회지
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• 제21권10호
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• pp.1452-1459
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• 2011

귤나무속은 운향과(Rutaceae)에 속한다. 동남아시아, 미얀마, 중국 운남에서 기원된 것으로 알려져 있다. 이 속의 분류관계는 복잡한데 클론번식과 야생식물과 교잡이 빈번하다. 식물에서 속간 속내 계통관계 추론을 위해 널리 이용되고 있는 엽록체 trnL-trnF 부위가 있다. 이 귤나무속과 두 근연한 탱자나무속과 금감속에 속하는 7종간 계통 관계를 평가하였다. 많은 삽입이 발견되었고 속내 종간 변이는 결실/삽입에 의한 것으로 밝혀졌다. 이 속의 레몬과 당귤나무은 네 계통도(MP, ML, ME, and NJ)에서 모두 같은 분지군을 형성하여 가장 근연관계에 있었고 광귤나무(향귤나무)과 자매군을 형성하였다. 유자나무는 이들과 많은 서열 차이를 나타내었다. 외부 분지군은 낮은 지지도를 나타내었다.

• ALGAE
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• 제30권4호
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• pp.265-274
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• 2015

Thorea indica sp. nov. is described from the Sai River, Uttar Pradesh, India (26°39′00.7″ N, 80°47′38.3″ E). Its classification is based on molecular sequences of the plastid-encoded RuBisCO large-subunit gene, rbcL and the barcode region of the mitochondrial encoded cytochrome c oxidase subunit 1, cox1, and morphological data. The sequence analyses confirm a new species of Thorea. The cox1 barcode sequence had 90.4-90.8% identity with Thorea sp. from Australia and Thorea hispida from Hawaii and China. Based on rbcL sequences the Indian specimen was positioned in a major clade with high support (>95 bootstrap and 0.95 posterior probability) containing two other species: T. okadae from Japan and T. hispida from the continental USA, Hawaii, the UK, and China. The divergences among these sequences were T. indica vs. T. okadae (2.8%) and T. indica vs. T. hispida (2.9-3.4%). The comparison of morphological characters of Thorea from India was not conclusive due to the inadequate descriptions in previous reports: most specimens reported as T. hispida fit within the circumscription of T. indica as described here. The previous report of T. siamensis from the Sai River is incorrect and the specimens fit within our description of T. indica. Thorea indica and T. okadae can be distinguished by minor morphometric characters and sexuality (dioecious vs. monoecious).

• ALGAE
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• 제33권2호
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• pp.157-166
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• 2018

Cryptic species complexes are increasingly recognized in phycological research, obscuring taxonomy and raising questions about factors influencing speciation. A recent exploration of kelp genetic diversity on Haida Gwaii, British Columbia revealed the existence of a new species, Saccharina druehlii, which is cryptic with Saccharina sessilis. This suggests that molecular investigations further north may be required to elucidate the taxonomy and evolutionary history of this lineage. Although, for several decades, S. sessilis was considered a single highly variable species, its taxonomy has been far from straightforward. In particular, Hedophyllum subsessile (Areschoug) Setchell is now recognized as a synonym of S. sessilis in North America, but as a growth form of Saccharina bongardiana in Far East Russia. To resolve this taxonomic confusion, we sequenced mitochondrial (CO1-5P) and nuclear (internal transcribed spacer) markers of S. sessilis populations from the Aleutian Islands, Alaska, USA. Interestingly, none of our sequences matched S. sessilis sensu stricto. Instead, CO1-5P sequences from populations in the central and eastern Aleutians matched exactly S. druehlii with increasing sequence divergence occurring westward. Samples from Attu, the western-most island, composed a genetic group that clearly represents Kjellman's concept of Hafgygia bongardiana f. subsessilis and is distinct enough from S. druehlii and S. sessilis to potentially constitute a distinct species. Therefore, Saccharina subsessilis comb. nov. is proposed for this entity. Our results suggest the existence of a species complex at the crown node of S. sessilis and thus further investigation of Saccharina in Alaskan waters should be conducted to reconstruct the evolutionary history of this fascinating lineage.

• Animal Systematics, Evolution and Diversity
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• 제27권1호
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• pp.1-17
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• 2011

Thais Roding, 1798, commonly known as rock-shell, is among the most frequently found gastropod genera worldwide on intertidal rocky shores including those of Japan, China, Taiwan and Korea. This group contains important species in many marine environmental studies but species-level taxonomy of the group is quite complicated due to the morphological variations in shell characters. This study examined the genetic variations and relationships among three Korean Thais species based on the partial nucleotide sequences of mitochondrial cox1 gene fragments. Phylogenetic trees from different analytic methods (maximum parsimony, neighbor-joining, and maximum likelihood) showed that T. bronni and T. luteostoma are closely related, indicating the most recent common ancestry. The low sequence divergence found between T. luteostoma and T. bronni, ranging from 1.53% to 3.19%, also corroborates this idea. Further molecular survey using different molecular marker is required to fully understand a detailed picture of the origin for their low level of interspecific sequence divergence. Sequence comparisons among conspecific individuals revealed extensive sequence variations within the three species with maximum values of 2.43% in T. clavigera and 1.37% in both T. bronni and T. luteostoma. In addition, there is an unexpectedly high level of mitochondrial genotypic diversity within each of the three Korean Thais species. The high genetic diversity revealed in Korean Thais species is likely to reflect genetic diversity introduced from potential source populations with diverse geographic origins, such as Taiwan, Hong Kong, and a variety of different coastal regions in South China and Japan. Additional sequence analysis with comprehensive taxon sampling from unstudied potential source populations will be also needed to address the origin and key factors for the high level of genetic diversity discovered within the three Korean Thais species studied.

• Animal Systematics, Evolution and Diversity
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• 제29권2호
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• pp.136-143
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• 2013

The collared scops owl that occurs in Korea is a protected species but its exact specific status has been questioned. To resolve the species status, a molecular phylogenetic analysis was conducted using two fragments of mitochondrial DNA, cytochrome b (cyt b, 891 bp) and NADH dehydrogenase subunit 2 (ND2, 627 bp) genes. Phylogenetic trees of cyt b revealed that all Korean specimens formed a monophyletic group with Japanese scops owl Otus semitorques with very low sequence divergence (d=0.008). We obtained a similar ND2 tree as well (d=0.003); however, the genetic distance between Korean individuals and O. lempiji from GenBank (AJ004026-7, EU348987, and EU601036) was very high and sufficient enough to separate them as species (cyt b, d=0.118; ND2, d=0.113). We also found that Korean species showed high differentiation from O. bakkamoena (AJ004018-20 and EU601034; cyt b, d=0.106; ND2, d=0.113) and O. lettia (EU601109 and EU601033, cyt b, d=0.110; ND2, d=0.117) as well. Therefore, we suggest that the Korean collared scops owl should be designated as Otus semitorques.