• 제목/요약/키워드: Polyphyletic

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16S rRNA 분석에 의한 Subsection IV cyanobacteria 균주들의 다계통성 기원의 증거 (Evidence for Polyphyletic Origin of the Members of the Subsection IV Cyanobacteria as Determined by 16S rRNA Analysis)

  • 신용국;서필수
    • 생명과학회지
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    • 제26권10호
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    • pp.1202-1206
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    • 2016
  • Subsection I과 II의 시아노박테리아 균주들은 단세포성이며, Subsection III의 시아노박테리아 균주들은 섬유상의 다계통성, 이형 사이토시스 형성성 균주들인 반면, Subsections IV와 V는 단일계통성으로 보고되어있다. 본 연구에서 13 균주의 시아노박테리아의 the small subunit rRNA (16S rRNA) 염기서열들이 - Subsection III의 Oscillatoria nigro-viridis PCC7112, Subsection IV에 속하는 Anabaena, Nostoc, Tolypothrix, Calothrix 및 Scytonema속을 포함한 6 균주, Subsection V에 속하는 Hapalosiphon, Fischerella and Chlorogloeopsis 속의 6 균주 - 결정되었다. 결정된 16S rRNA 염기서열을 이용하여 시아노박테리아의 분자계통분석을 수행하였다. 그러나, 16S rRNA의 염기서열 결정을 근거로 한 본 연구의 계통분석결과 Subsection IV는 단일 계통성이 아닌 다계통성이며, 반면 Subsection V는 이전에 보고되어진 것처럼 단일 계통성임을 나타내었다. 또한, 본 연구 결과는 Scytonema속이 이형 사이토시스 형성성 시아노박테리아인 Subsection IV 및 V의 공통 조상일 수 있음을 강력하게 나타낸다. 부가적으로, 본 연구의 분자계통 분석을 통해 Anabaena속은 다계통성으로 계통학적으로 다양한 종들로 구성되어 있음을 나타내고 있다. 본 연구 결과는 Anabaena속이 좀 더 세밀하게 재분류 되어져야 함을 나타낸다.

Phylogenetic Relationships among Diverse Dinoflagellate Species Occurring in Coastal Waters off Korea Inferred from Large Subunit Ribosomal DNA Sequence Data

  • Kim, Keun-Yong;Kim, Chang-Hoon
    • ALGAE
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    • 제22권2호
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    • pp.57-67
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    • 2007
  • We analyzed the nuclear-encoded large subunit ribosomal RNA gene (LSU rDNA) sequences of 19 dinoflagellates occurring in costal waters off Korea and reconstructed a phylogenetic tree containing 74 representative species from 37 distinct genera. Of these, the LSU rDNA sequences of Amylax triacantha (Jörgensen) Sournia, Gonyaulax verior Sournia (= Amylax diacantha Meunier), Gyrodinium fissum (Levander) Kofoid et Swezy, Katodinium glaucum (Lebour) Lebour III, Noctiluca scintillans (Macartney) Kofoid et Swezy, Oxyphysis oxytoxoides Kofoid, and Pyrophacus steinii (Schiller) Wall et Dale are reported for the first time. Our LSU rDNA tree consistently placed Oxyrrhis marina Dujardin and N. scintillans at the most primitive positions, giving rise to a strongly supported monophyletic group of typical dinoflagellate species belonging to the Dinophyceae. The phylogenetic relationships among the typical dinoflagellates, however, were not resolved in the higher taxonomic levels in general. Only genera at terminal branches were usually supported with high confidence. The Dinophysiales, represented by Dinophysis species and O. oxytoxoides, formed a strongly supported monophyletic assemblage. The Gymnodiniales and Peridiniales were recovered as polyphyletic groupings. Members of the Gonyaulacales were consistently grouped together, but lacked statistical support. Within this order, the Ceratiaceae and Goniodomataceae each formed a monophyletic group, but the Gonyaulacaceae was polyphyletic. The phylogenetic relationships of the Gonyaulacaceae were generally congruent with differences in the combinations of the apical pore complex, hypothecal organization and thecal formula.

New Report of Three Unrecorded Species in Trichoderma harzianum Species Complex in Korea

  • Jang, Seokyoon;Kwon, Sun Lul;Lee, Hanbyul;Jang, Yeongseon;Park, Myung Soo;Lim, Young Woon;Kim, Changmu;Kim, Jae-Jin
    • Mycobiology
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    • 제46권3호
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    • pp.177-184
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    • 2018
  • The genus Trichoderma (Hypocreaceae, Ascomycota) consists of globally distributed fungi. Among them, T. harzianum, one of the most commonly collected Trichoderma species, had been known as a polyphyletic or aggregate species. However, a total of 19 species were determined from the polyphyletic groups of T. harzianum. Thus, we explored Korean "T. harzianum" specimens that were collected in 2013-2014. These specimens were re-examined based on a recent study with translate elongation factor 1-alpha ($EF1{\alpha}$) sequences to reveal cryptic Trichoderma species in Korea. As a result, four different species, T. afroharzianum, T. atrobruneum, T. pyramidale, and T. harzianum, were identified. Except T. harzianum, the other three species have not been reported in Korea. In this work, we describe these species and provide figures.

Phylogenetic Evaluation of Stereoid Fungi

  • Yoon, Sung-Il;Kim, Seon-Young;Lim, Young-Woon;Jung, Hack-Sung
    • Journal of Microbiology and Biotechnology
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    • 제13권3호
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    • pp.406-414
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    • 2003
  • Phylogenetic relationships of stereoid fungi were examined by comparing nuclear small subunit ribosomal RNA gene sequences. Stereoid taxa were scattered into several groups and the traditional Stereaceae proved to be polyphyletic. Srereum and Xylobolus were classified in the Stereaceae as the core group of stereoid fungi, and Amylostereum was grouped with Echinodontium of the Echinodontiaceae. Chondrostereum and Cystosrereum were clustered in the Stereaceae sensu Donk and Cymatoderma and Podoscypha in the Podoscyphaceae Reid. Columnocystis abietinum and C. ambigua were grouped with Meripilus giganteus and proved to be not included in the Chaetodermataceae sensu Nakasone. Lopharia cinerascens and L. mirabilis were grouped together but L. spadicea was unrelated to them, indicating that Lopharia is heterogeneous at a generic level.

Phylogenetic study of trichaptum inferred from nuclear ribosomal DNA sequences

  • Ko, Kwon-Soo;Hong, Soon-Gyu;Jung, Hack-Sung
    • Journal of Microbiology
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    • 제35권2호
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    • pp.79-86
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    • 1997
  • For the phylogenetic study of the genus Trichaptum, nuclear ribosomal DNA sequences from eight strains of four Trichaptium species were examined. Phylogenetic trees were constructed using molecular data on 18 rDNA and 5.8S rDNA and thei ITSs. Parsimony analyses of the Trichaptum species showed that T. biforme and T. laricinum made a monophyletic group respectively, suggesting that each species is phylogenetically independent. However, T. abietum represented a polyphyletic group and T. fusco-violaceum formed a polytomous group, suggesting that these species could be in the process of evolutionary differentiation. Examination of base substitutions of the 18S rRNA gene reveals that the C-T transition is most predominant and that there is a stronger transition bias between closely related organisms rather than between distantly related ones.

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먹물버섯류(Coprinus spp.)의 ITS II 영역 염기서열에 의한 유연관계 분석 (Genetic Relationships of Coprinus spp. on the Basis of Sequences in ITS II Region)

  • 박동석;고승주;김양섭;석순자;송재경;여윤수;류진창;성재모
    • 한국균학회지
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    • 제27권1호통권88호
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    • pp.27-31
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    • 1999
  • 먹물버섯속(Coprinus spp.)의 분자 생물학적 분류 가능성을 모색하기 위해 rDNA의 cluster중 ITS II영역을 PCR 증폭하여 염기서열을 밝혔다. 이들의 ITS II 영역은 $253{\sim}275$ 염기쌍으로 이루어져 있었으며 균주간 ITS II염기서열의 유사도는 $50.3{\sim}100%$로 나타났다. 이들의 염기서열을 이용해 분류도를 작성한 결과, Singer의 형태적 분류체계와 거의 유사한 결과를 보였으나 이들 그룹의 기준종(type species)인 C. comatus는 기타 종들과의 유사도에서 50% 수준의 저조한 상동성을 보여 주었다. 이와 같은 결과로 볼 때 이 종은 기존의 다수 학자들이 보고한 단일 계통진화를 해온 속이란 점에서는 다소 의문점을 남기었고, ITS II 영역은 종내 변이는 없는 것으로 보여지며 종내의 균주간의 변이가 밝혀진 그룹에 대해서는 종에 대한 재검토가 필요하다고 본다.

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Molecular Characterization of Marine Cyanobacteria from the Indian Subcontinent Deduced from Sequence Analysis of the Phycocyanin Operon (cpcB-IGS-cpcA) and 16S-23S ITS Region

  • Premanandh, Jagadeesan;Priya, Balakrishnan;Teneva, Ivanka;Dzhambazov, Balik;Prabaharan, Dharmar;Uma, Lakshmanan
    • Journal of Microbiology
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    • 제44권6호
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    • pp.607-616
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    • 2006
  • Molecular characterization of ten marine cyanobacterial isolates belonging to the order Oscillatoriales was carried out using the phycocyanin locus (cpcBA-IGS) and the 16S-23S internally transcribed spacer region. DNA sequences from the phycocyanin operon discriminated ten genotypes, which corresponded to seven morphotypes identified by traditional microscopic analysis. The cpcB coding region revealed 17% nucleotide variation, while cpcA exhibited 29% variation across the studied species. Phylogenetic analyses support the conclusion that the Phormidium and Leptolyngbya genera are not monophyletic. The nucleotide variations were heterogeneously distributed with no or minimal informative nucleotides. Our results suggest that the discriminatory power of the phycocyanin region varies across the cyanobacterial species and strains. The DNA sequence analysis of the 16S-23S internally transcribed spacer region also supports the polyphyletic nature of the studied oscillatorian cyanobacteria. This study demonstrated that morphologically very similar strains might differ genotypically. Thus, molecular approaches comprising different gene regions in combination with morphological criteria may provide better taxonomical resolution of the order Oscillatoriales.

Molecular Phylogeny and Divergence Time Estimation of the Soft Coral Dendronephthya gigantea (Alcyonacea: Nephtheidae)

  • Kim, Boa;Kong, So-Ra;Song, Jun-Im;Won, Yong-Jin
    • Animal Systematics, Evolution and Diversity
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    • 제24권3호
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    • pp.327-332
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    • 2008
  • Soft coral Dendronephthya gigantea (Verrill, 1864) is a conspicuous species dominating shallow sea waters of Jejudo Island, Korea. Recently its whole mitochondrial genome sequencing was completed by us and the sequence information provided an opportunity to test the age of Octocorallia and time of evolutionary separation between some representative orders of the subclass Octocorallia. Molecular phylogenetic analyses based on 13 mitochondrial protein encoding genes revealed a polyphyletic relationship among octocorallians representing two orders (Alcyonacea and Gorgonacea) and four families (Alcyoniidae, Nephtheidae, Briareidae, and Gorgoniidae). Estimates of divergence times among octocorallians indicate that the first splitting might occur around end of or after Cretaceous period (50-79 million years ago (Ma)). The age is relatively young compared to the long history of stony sea corals (>240 Ma). Taken together our result suggests a possible relatively recent radiating evolution at least in the order Alcyonacea and Gorgonacea. Molecular dating and phylogenetic analysis based on much broader taxon sampling and many genes might give an insight into this interesting hypothesis.

Diversity of the Lichenized Fungi in King George Island, Antarctica, Revealed by Phylogenetic Analysis of Partial Large Subunit rDNA Sequences

  • Lee, Jin-Sung;Lee, Hong-Kum;Hur, Jae-Seoun;Andreev, Mikhail;Hong, Soon-Gyu
    • Journal of Microbiology and Biotechnology
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    • 제18권6호
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    • pp.1016-1023
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    • 2008
  • Lichens are predominant and important components of flora in the terrestrial ecosystem of Antarctica. However, relatively few researches on the phylogenetic position of Antarctic lichen-forming fungi have been accomplished. In this study, partial sequences of nuclear large subunit rDNAs from 50 Antarctic specimens were obtained and the phylogeny was reconstructed. Antarctic lichen species were distributed in 4 orders, including the monophyletic order Agyrales, paraphyletic orders Pertusariales and Teloschistales, and polyphyletic order Lecanorales. Species diversity was highest in the order Lecanorales, followed by Teloschistales and Pertusariales. Based on the phylogeny and sequence similarity analyses, it is proposed that the taxonomy of Stereocaulon alpinum, Physcia caesia, Usnea aurantiacoatra, and Cladonia species should be revised by careful examination of their phenotypic and molecular characteristics. Six species known to be endemic to Antarctica, Catillaria corymbosa, Himantormia lugubris, Leptogium puberulum, Pertusaria pertusa, Rhizoplaca aspidophora, and Umbilicaria antarctica, formed unique lineages, implying independent origins in the Antarctic area.