• Journal of Life Science
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• v.9 no.1
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• pp.15-21
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• 1999

The random amplified ploymorphic DNAs (RAPD) assay is a simple and useful tool in identification of appropriate genetic markers, that requires no knowledge of target DNA sequence. RAPD products were generated directly from seaweed tissues, without prior nucleic acid extraction, of Porphyra yezoensis, Ulva pertusa and Undaria pinnatifida. The nuclear rDNA internal transcribed spacer (ITS) fragment however was not amplified directly from the seaweed tissues. Using DNA extracted by the LiCl method, both the ITS and RAPD's have been amplified by the polymerase chain reaction. RAPD of P yezoensis, thallus (n) and conchocelis (2n) produced lots of different polymorphic bands (36-50$\%$) depending on the arbitrary primers used. Difference was also observed between direct tissues amplification and DNA extracts amplification (53-57$\%$). Thus it is important to use the same ploidy of tissue for DNA extraction and as a RAPD template.

• The Korean Journal of Mycology
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• v.44 no.3
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• pp.184-187
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• 2016

Endophytic fungi were isolated from surface-sterilized roots of a species of orchid, Oreorchis patens, in Korea. The isolated strains were identified based on morphological characteristics and sequence analyses of the internal transcribed spacer (ITS) and large subunit (LSU) of rDNA regions. Two species, Thelonectria veuillotiana and Phialocephala humicola, are first reported in Korea with their descriptions.

• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.816-821
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• 2004

A reliable molecular phylogenetic method to identify Hericium erinaceum, the most industrially valuable species in the Hericium genus, was established. Sequencing and phylogenetic analyses of the PCR-amplified ITS and 5.8S rDNA from Hericium fungi, including 6 species and 23 isolates, showed that variation in nucleotide sequences and size exists in both ITS1 and ITS2 regions, but not in the 5.8S region. These two ITS regions provided different levels of information on the relationship of H. erinaceum to other Hericium species. Based on the ITS1 sequence, both the parsimony and neighbor joining trees clearly distinguished Asian H. erinaceum isolates from other Hericium species and isolates. The intraspecific divergence of the ITS2 region was suitable to dissect the Asian H. erinaceum isolates into a few groups.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.419-426
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• 2006

A thermophilic microorganism, strain JE 375, which produces a thermostable protease, was isolated from soil and compost in Korea. This gram-positive, rod-shaped, catalase positive, motility positive, and hemolysis ${\beta}$ containing organism was implicated in glucose fermentation, mannitol fermentation, xylose oxidation, aerobic activity and spore formation. The color of the colony was yellowish white. The temperature range for growth at pH 6.5 was between 55 and $70^{\circ}C$, with an optimum growth temperature of $65^{\circ}C$. This result confirmed the strain JE 375 as a thermophilic microorganism. The enzyme was produced aerobically at $65^{\circ}C$ during 20 hr in a medium (pH 6.5) containing 1% trypton. 1% maltose, 0.5% yeast extract and 1% NaCl. The 16S rDNA of strain JE 375 had 97.6% sequence similarity with the 16S rDNA of Bacillus caldoxyloyticus. On the basis of biochemical and physiological properties and phylogenetic analysis, we named the isolated strain as Bacillus sp. JE 375. The thermostable protease from Bacillus sp. JE 375 had been partially purified and characterized. The molecular weight of the enzyme was deduced from SDS-PAGE and gel chromatography as 55 kDa and its optimal temperature was $60^{\circ}C$. The enzyme showed its highest activity at pH 7.5 and was stable from pH 7.0 to 8.0.

• The Korean Journal of Mycology
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• v.40 no.3
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• pp.174-176
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• 2012

We report morphological and physiological characteristics of newly isolated six kinds of yeasts which are new in Korean mycoflora. The yeasts were isolated from wild flowers in Daejeon city, Korea and identified by molecular analysis of the amplified internal transcribed space rDNA sequence or partial 18S rDNA sequence. Species of isolates were identified as Kuraishia capsulate, Lodderomyces elongisporus, Pseudozyma antarctica, Starmerella bombicola.

• Mycobiology
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• v.38 no.1
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• pp.17-25
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• 2010

The common split-gilled mushroom, Schizophyllum commune is found throughout the world on woody plants. This study was initiated to evaluate conditions for favorable vegetative growth and to determine molecular phylogenetic relationship in twelve different strains of S. commune. A suitable temperature for mycelial growth was obtained at $30^{\circ}C$. This mushroom grew well in acidic conditions and pH 5 was the most favorable. Hamada, glucose peptone, Hennerberg, potato dextrose agar and yeast malt extract were favorable media for growing mycelia, while Lilly and glucose tryptone were unfavorable. Dextrin was the best and lactose was the less effective carbon source. The most suitable nitrogen sources were calcium nitrate, glycine, and potassium nitrate, whereas ammonium phosphate and histidine were the least effective for the mycelial growth of S. commune. The genetic diversity of each strain was investigated in order to identify them. The internal transcribed spacer (ITS) regions of rDNA were amplified using PCR. The size of the ITS1 and ITS2 regions of rDNA from the different strains varied from 129 to 143 bp and 241 to 243 bp, respectively. The sequence of ITS1 was more variable than that of ITS2, while the 5.8S sequences were identical. A phylogenetic tree of the ITS region sequences indicated that the selected strains were classified into three clusters. The reciprocal homologies of the ITS region sequences ranged from 99 to 100%. The strains were also analyzed by random amplification of polymorphic DNA (RAPD) with 20 arbitrary primers. Twelve primers efficiently amplified the genomic DNA. The number of amplified bands varied depending on the primers used or the strains tested. The average number of polymorphic bands observed per primer was 4.5. The size of polymorphic fragments was obtained in the range of 0.2 to 2.3 kb. These results indicate that the RAPD technique is well suited for detecting the genetic diversity in the S. commune strains tested.

• Journal of Life Science
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• v.18 no.4
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• pp.447-453
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• 2008

Zinc is an essential trace element in Human Being. Highly zinc containing yeast strain isolated from the tropical fruit, rambutan and the zinc concentration in this yeast strain was 306 ppm (30.6 mg%)per dry matter basis. This strain was found to be a rounded type, normal size, and multi-polar budding. Phylogenetic analysis using the ITS1-5.85 rDNA sequences from isolated strain is most similar to yeast Saccharomyces cerevisiae at the level of nucleotide sequence identity at 99%. This strain was produced alcohol by about 12% using fully colonized koji-rice with Aspergillus oryzae. In conclusion, the isolated strain was found to be closely related to the S. cerevisiae based on its morphological and physiological properties, and alcohol fermentation. The phylogenetic analysis of strain FF-10 using ITS 5.8S rDNA sequence data also supported the closely related to the S. cerevisiae. Accordingly, the isolated yeast was named as S. cerevisiae FF-10. Further studies on the best culture conditions for zinc production from zinc-enriched S. cerevisiae FF-10 are under investigation.

• Journal of Microbiology and Biotechnology
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• v.12 no.6
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• pp.989-992
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• 2002

Sweet persimmon (Diospyros kaki Thunb.) is widely cultivated in the southern part of Korea and its cultivation is increasing. However, anthracnose disease caused by Colletotricuhum species is one of the major hinderances to the cultivation and production of sweet persimmon. Therefore, in the current study, PCR was used to specifically detect Colletotrichum spp., based on the sequences of the ITS II regions in the rDNA. Using the sequence data, CO-1 was designated to detect Colletotrichum together the with ITS 4 primer. The result showed that a single segment of ca. 500 bp was observed only in Colletotrichum, but not in any other fungal and bacterial isolates. The annealing temperatures and template DNA quantites were also investigated to identify optimal conditions for detection. Using these species-specific primers, a unique band was obtained at annealing temperatures ranging from $55^{\circ}C\;and\;61^{\circ}C$ and template DNA levels from 10 pg- $10{\mu}g$.

• Mycobiology
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• v.37 no.4
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• pp.258-266
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• 2009

Pleurotus eryngii, known as king oyster mushroom has been widely used for nutritional and medicinal purposes. This study was initiated to screen the suitable conditions for mycelial growth and to determine the phylogenetic relationship of the selected strains. Optimal mycelial growth was observed at $30{^{\circ}C}$ and minimum mycelial growth observed at $10{^{\circ}C}$. This mushroom tolerates a broad pH range for mycelial growth, with most favorable growth observed at pH 6. Results also indicated that glucose peptone, yeast malt extract and mushroom complete media were favorable growth media, while Hennerberg and Hoppkins media were unfavorable. Dextrin was the best and xylose the least effective carbon sources. Results revealed that inorganic nitrogen sources were less effective than organic sources for the mycelial growth of P. eryngii. Investigation of genetic diversity is necessary to identify the strains. The ITS region of rDNA were amplified using PCR. The size of the ITS1 and ITS2 regions of rDNA from the different strains varied from 214 to 222 bp and 145 to 236 bp, respectively. The sequence of ITS2 was more variable than that of ITS1, and the 5.8S sequences were identical. A phylogenetic tree based on the ITS region sequences indicated that selected strains could be classified into six clusters. Fourteen IUM and ATCC- 90212 strains were also analyzed by RAPD with 20 arbitrary primers. Fourteen of these primers were efficiently amplified the genomic DNA. The number of amplified bands varied with the primers and strains, with polymorphic fragments in the range from 0.2 to 2.3 kb.

• The Plant Pathology Journal
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• v.28 no.1
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• pp.49-54
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• 2012

In August 2010, a severe crown rot was observed on chrysanthemum ($Chrysanthemum$ $morifolium$ Ramat., variety Sinro) in several greenhouses located at Damyang and Muan, Jeonnam province, Korea. Three isolates (EML-CHS1, -CHS2, and -CHS3) of $Fusarium$ were isolated from the affected plants and identified based on morphological characteristics and rDNA internal transcribed spacer (ITS) sequence analysis. Sequence analysis by BLAST indicated that EMLCHS1, -CHS2 and CHS3 were closest to a $Fusarium$ species, $F.$ $solani$ with > 99% sequence similarity. Pathogenicity tests were performed on chrysanthemum with spore suspensions containing $3.4{\times}10^6$ spores/ml using the dipping method. Ten days after inoculation, similar symptoms to those observed in the greenhouses were seen on the inoculated plants. The causal fungus was reisolated from the artificially inoculated basal stems, fulfilling Koch's postulates. To our knowledge, this is the first report of crown rot by $Fusarium$ $solani$ on chrysanthemum ($Chrysanthemum$ $morifolium$) in Korea.