• Animal Systematics, Evolution and Diversity
• /
• 제38권4호
• /
• pp.274-278
• /
• 2022

One marine ciliate, Diophrys quadrinucleata Zhang et al., 2020 was newly recorded from South Korea in this study. We provided morphological diagnosis and images of the Korean D. quadrinucleata population. We determined the small subunit ribosomal DNA (SSU rDNA) and cytochrome oxidase subunit I (CO1) sequence data of D. quadrinucleata, and then the sequences were compared with other Diophrys species. Intra-specific variation between the Korean and type (Chinese) populations was identical in the SSU rDNA, while the inter-specific variations between seven Diophrys species were 0.3-3.8% in the SSU rDNA and 12.6-18.2% in the CO1. In this study, we obtained 18S and CO1 data from species with identified morphology. As the importance of securing 18S and CO1 based on morphology increases in current studies, this study will contribute to ciliate studies.

• ALGAE
• /
• 제20권1호
• /
• pp.25-30
• /
• 2005

To clarify some confusions concerning identification of the Korean Peridinium species, genotypic analysis was performed with their SSU rDNA sequences. PCR was used to amplify the partial SSU rDNA of Peridinium isolates collected from three different Korean waters (Juam, Sang-sa and Togyo Reservoirs). The PCR products were allowed directly to sequence, which revealed each 942 bp of rDNA sequence. Analyses of the rDNA sequences showed that all the Korean isolates had the same genotype (100% sequence homology), and they were nearly identical to a Japanese strain of P. bipes f. occultatum (NIES 364; 99.8% sequence similarity). The sequence-based comparisons could clearly resolve P. bipes f. occultatum isolated from three different Korean waters.

• Journal of Microbiology and Biotechnology
• /
• 제14권5호
• /
• pp.959-966
• /
• 2004

Twenty-three cultures of harmful algal bloom (HAB)-(causing dinoflagellates were isolated from the coastal waters of Korea. For each of the 14 morphospecies, the nuclearencoded small subunit (SSU) rDNA was analyzed to determine the phylogenetic relatedness of the species. Despite temporal and spatial isolation, 3-4 clonal cultures of Alexandrium catenella, Cochlodinium polykrikoides, and Gymnodinium catenatum had 100% identical SSU rDNA sequences. In contrast, heterogeneities in the SSU rDNA sequences were observed in Akashiwo sanguinea and Lingulodinium polyedrum strains. Extreme sequence polymorphism was shown within the SSU rRNA genes of an Al. tamarense clonal culture. A homology search in GenBank revealed that 11 dinoflagellate species were located in clusters corresponding to their morphological classification. The SSU rDNA sequences of C. polykrikoides, Gyrodinium instriatum, and Pheopolykrikos hartmannii, which were determined for the first time in this study, showed the following phylogenetic relationships: C. polykrikoides formed an independent branch separated from other dinoflagellates; Gyr. instriatum was placed in a monophyletic group with Gyr. dorsum and Gyr. uncatenum; and Ph. hartmanii, which forms a distinct two-celled pseudocolony, belonged to Gymnodinium sensu Hansen and Moestrup.

• ALGAE
• /
• 제19권2호
• /
• pp.79-90
• /
• 2004

Nuclear DNA contents of spermatia from eight ceramiacean and four dasyacean algae (Ceramiales, Rhodophyta) and microspores from two land plants were estimated by fluorescence microscopic image processing and their nuclear SSU rDNA sequence data were analyzed. In frequency distribution patterns, the DAPI-stained nuclear volume (NV) of spermatia showed two peaks corresponding to 1C and 2C. Nuclear 2C DNA contents estimated from NV were 0.45-2.31 pg in ceramiacean and 0.40-0.57 pg in dasyacean algae and 8.42-9.51 pg in two land plants, Capsicum annuum and Nicotiana tabacum. By nuclear patterning of vegetative cells derived from an apical cell, 2C DNA contents of spermatia were 2.31 pg in an alga having uninucleate and non-polyploid nucleus (Aglaothamnion callophyllidicola), 0.45-1.94 pg in algae having uninucleate and polyploid nucleus (Antithamnion spp. and Pterothamnion yezoense), and 0.40-0.62 pg in algae having multinucleate and non-polyploid nuclei (Griffithsia japonica and dasyacean algae). Each mature spermatium and microspore (pollen grain) seemed to have a 2C nucleus, which may provide a genetic buffering system to protect the genetic content of a spermatium and microspore from potentially lethal mutations. Nuclear DNA content and SSU rDNA sequence of Antithamnion sparsum from Korea were reasonably different from those of Antithamnion densum from France. The data did not support the previous taxonomic studies that these two taxa could be conspecific.

• 생명과학회지
• /
• 제23권10호
• /
• pp.1260-1266
• /
• 2013

본 연구에서는 H. marmoreus 3-10균주와 H. marmoreus 1-1균주의 ribosomal DNA (rDNA) cluster의 분석이 수행되었다. Small subunit (SSU)와 intergenic spacer 2 (IGS 2)는 부분적으로 염기서열이 결정되었고, internal transcribed spacer 1 (ITS 1), 5.8S, internal transcribed spacer 2 (ITS 2), large subunit (LSU), intergenic spacer 1 (IGS 1), 5S는 완전하게 염기서열이 결정 되었다. 팽이버섯 H. marmoreus 3-10균주와 H. marmoreus 1-1균주의 rDNA cluster는 총 7,049 bp로 결정되었다. SSU은 1,796 bp, ITS1은 229 bp, 5.8S은 153 bp, ITS2는 223 bp, LSU은 3,348 bp, IGS1은 390 bp, IGS2은 900 bp로 염기서열이 분석되었다. 결정된 rDNA cluster의 총 7,049 bp 중에서 17 bp가 다름이 확인되었고, 각각 SSU (2 bp), ITS (3 bp), LSU (9 bp), IGS (3 bp)에서 차이를 확인하였다. ITS regions의 2차 구조 결과 5개의 stem-loop가 있음이 드러났다. 흥미롭게도, 이들 stem-loop 사이에서 stem-loop V에서 한 개의 상이한 염기가 다른 2차 구조를 나타냄을 확인하였다.

• Ocean Science Journal
• /
• 제40권3호
• /
• pp.155-166
• /
• 2005

New PCR primers (N=18) were designed for the isolation of complete SSU to LSU rDNA sequences from the dinoflagellate Alexandrium tamarense. Standard PCR, employing each primer set selected for amplifications of less than 1.5 kb, successfully amplified the expected rDNA regions of A. tamarense (Korean isolate, HY970328M). Complete SSU, LSU rDNAs and ITS sequences, including 5.8S rDNA, were recorded at 1,800 bp, 520 bp and 3,393 bp, respectively. The LSU rDNA sequence was the first report in Alexandrium genus. No intron was found in the LSU rRNA coding region. Twelve D-domains within the LSU rDNA were put together into 1,879 bp (44.4% G+C), and cores into 1514 bp (42.8% G+C). The core sequence was significantly different (0.0867 of genetic distance, 91% sequence similarity) in comparison with Prorocentrum micans (GenBank access. no. X16108). The D2 region was the longest in length (300 bp) and highly variable among the 12 D-domains. In a phylogenetic analysis using complete LSU rDNA sequences of a variety of phytoplankton, A. tamarense was clearly separated with high resolution against other species. The result suggests that the sequence may resolve the taxonomic ambiguities of Alexandrium genus, particularly of the tamarensis complex.

• Journal of Microbiology
• /
• 제38권2호
• /
• pp.62-65
• /
• 2000

Partial sequence comparisons of mitochondrial small subunit rDNA (mt SSU rDNA) were used to examine taxonomic and evolutionary relationships among seven Penicillium species : two monoverticillate species, two biverticillate species, and three terverticillate species. Amplified fragments of mt SSU rDNA highly varied among seven species in size, suggesting the existence of multiple insertions or deletions in the region. A phylogengtic tree was constructed by exhaustive search of parsimony analysis. The phylogenetic tree distinguished two statistically supported monophyletic groups, one for two monoverticillate species and the other for three terverticillate species and ont biverticillate species, P. vulpinum. The phylogenetic relationship of P. waksmanii, the biverticillate species, was not clear.

• Parasites, Hosts and Diseases
• /
• 제49권3호
• /
• pp.281-284
• /
• 2011

Amebiasis is a protozoan disease caused by Entamoeba histolytica and a potential health threat in areas where sanitation and hygiene are inappropriate. Highly sensitive PCR methods for detection of E. histolytica in clinical and environmental samples are extremely useful to control amebiasis and to promote public health. The present study compared several primer sets for small subunit (SSU) rDNA and histone genes of E. histolytica cysts. A 246 bp of the SSU rDNA gene of pure cysts contained in phosphate-buffered saline (PBS) and in stool samples was successfully amplified by nested PCR, using the 1,147-246 bp primer set, of the primary PCR products which were pre-amplified using the 1,147 bp primer as the template. The detection limit of the nested PCR using the 1,147-246 primer set was 10 cysts in both groups (PBS and stool samples). The PCR to detect histone gene showed negative results. We propose that the nested PCR technique to detect SSU rDNA can be used as a highly sensitive genetic method to detect E. histolytica cysts in stool samples.

• 미생물학회지
• /
• 제49권3호
• /
• pp.270-274
• /
• 2013

서양뒤영벌(Bombus terrestris)은 꿀벌의 봉군붕괴증후군(colony collapse disorder)에 대한 대체 화분매개곤충으로서 농업분야에서 중요한 역할을 하고 있다. 최근 서양뒤영벌에서 바이러스, 세균, 응애 등의 여러 병원체와 기생체가 발견되었고, 이들은 서양뒤영벌의 수명과 생식력 등에 영향을 주는 것이 알려져 있다. 서양뒤영벌 야외개체군에서 Nosema spp.를 탐지하기 위해, 서양뒤영벌 성충으로부터 genomic DNA를 추출하여 Nosema spp. 유전자들에 대해 polymerase chain reaction (PCR)을 수행하였다. 이들 유전자 중에서 small subunit ribosomal RNA (SSU rRNA) 유전자만이 증폭되었고, 염기서열분석을 통해 N. ceranae로 확인된 것은 조사된 야외개체군에서 N. ceranae가 서양뒤영벌의 주된 감염체임을 보여준다. Quantitative real-time PCR (qRT-PCR)을 이용하여 SSU rRNA 유전자를 탐지하기 위해, 먼저 PCR을 통해 SSU rRNA 유전자의 2개 영역에 대한 유전자 특이적 증폭을 확인하였다. qRT-PCR을 이용하여 각 개체에서 얻은 genomic DNA의 순차적인 농도희석를 통해 $0.85ng/{\mu}l$ 이하의 genomic DNA 농도에서도 SSU rRNA 유전자가 성공적으로 증폭되는 것이 확인되었다. 이러한 실험 결과, qRT-PCR를 이용한 N. ceranae 특이 유전자 증폭은 서양뒤영벌의 병원체 감염 진단 뿐만 아니라 생태계 위해성 평가에도 활용될 수 있을 것으로 사료된다.

• Parasites, Hosts and Diseases
• /
• 제36권1호
• /
• pp.47-54
• /
• 1998

소의 주혈원충인 Reileria sp.의 small subunit ribosomal RMh (SSU rRNA) 유전자의 염 기서 열분 석을 위해 한국의 전북 장수로부터 분리하여 계대보관 중인 실험실 보관주 (KLS)와 김제 분리주 (KCB), 그리고 일본의 Shintoku 분리주 (JHS)를 실험에 사용하였다. 이들 분리주로 부터 원충을 회수 한 후 유전자를 추출하여 중합효소연쇄반응에 의 해 1.8 kb의 SSU rRNA 유전자를 증폭시 킬 수 있었으며, 증폭된 유전자를 이용하여 클론을 제작하고. 이들 클론으로 부터 플라스미드를 추출하여 유전자 염기서열분석을 실시하였다. 각 ReTheileria 분리주의 SSU rRNA유전자의 염기서열분석은 forma터와 reverse양쪽 다중복하여 실시하였으며 연속적인 primer를 이용하였다. 그 결과 한국의 소로부터 분리 한 Theue4n sp. (KLS. KCB)의 SSU rRNA유전자 염 기서 열 (Type A로 명명하였슴)은 일본 분리주와 동 일하였으며, 이 Type A를 GenBank로부터 유전자 검색을 해본 결과 Kenya의 Marula 분리주인 Reixerin buffeli의 SSU rRNA유전자 염기서열과 일치 하였다.