• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.117.3-118
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• 2003

We tested for the presence of double-stranded RNA (dsRNA) mycovirus in 827 Fusarium graminearum isolated from diseased barley and maize. dsRNA mycoviruses with various sizes were isolated. Of them, it was previously reported that dsRNA from DK2l isolate had pronounced morphological changes, including reduction in mycelial growth, increased to red pigmentation, reduced virulence and sporulation. (Chu et al., Appl. Environ. Microbiol. 2002). For better understanding of this hypovirulence associated with DK2l dsRNA virus, we determined the complete nucleotide sequence of dsRNA genome and named Fusarium hypovirus DK2l strain (Fhv-DK2l ). Genomic RNA of Fhv-DK2l was determined to be 6625 nucleotides in length excluding the poly (A) tail and contained three putative open reading frame. RNA-dependent RNA polymerase (RdRp) and helicase domain were expected in ORF A, 54 to 4709 nucleotide position. ORE B, 4752 to 5216 nucleotide position, and ORF C, 5475 to 6578 nucleotide position, were predicted to encode 16.7kDa and 41.3kDa protein respectively each. We could not detect any conserved domains from these two proteins. Phylogenetic analysis showed Fhv-DK2l was related to Cryphonectria hypovirus 3. Ten additional isolates were found that were infected with dsRNA mycoviruses. These mycoviruses contain 2 to 4 different segments of dsRNAs with the size range of approximately 1.7 to 10-kbp in length. The presence of dsRNAs isolates did not affect colony morphology and were transmissible through conidia and ascospore with incidence of 30-100％. These results indicate that there is genomic diversity of dsRNA mycoviruses that infect F. graminearum isolates and that impact of virus infection on host's morphology and virulence is determined by the interaction between dsRNAs and the fungal host, not by the mere presence of the dsRNAs

• 한국균학회지
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• 제16권1호
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• pp.16-20
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• 1988

영지(靈芝)의 항암물질개량(抗癌物質改良)과 신품종(新品種)의 육성(育成)을 위(爲)한 (육종역법)育種方法으로 제시된 원형질체융합(原形質體融合)의 기초자료를 얻고자 영양요구성균주(營養要求性菌株)의 선발(選拔), 종간원형질체융합(種間原形質體融合)과 융합균주(融合菌株)의 선발(選拔)을 실험(實驗)하였다. 1. 돌연변이(突然變異) 대상체(對相體)로는 균사체(菌絲體), mutagen으로는 자외선(紫外線)을 사용하였는데 영양요구성균주(營養要求性菌株)의 유기율(誘起率)은5.78%이었다. 2. 영지(靈芝)와 잔나비걸상버섯간(間) 원형질체융합률(原形質體融合率)은 2.03%이었다. 3. 융합균주(融合菌株)는 환원균총(還元菌叢)의 생장속도(生長速度)와 형태(形態)를 비교(比較)하여 선발(選拔)하였고, 계대배양후(繼代培養後)의 형태(形態)와 esterase isozyme pattern의 분석(分析)에 의해서 확인(確認)하였으며, 참나무톱밥배지(培地)에서 재배(栽培)하여 자실체(子實體)를 관제(觀祭)하였다.

• Environmental Analysis Health and Toxicology
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• 제23권2호
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• pp.101-112
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• 2008

Effects of various concentrations of copper on growth change of blue-greenalgae Anabaena flos-aquae were studied. There was significant differences among cultures treated with various concentrations of copper in growth of algae with parameters of cell numbers, specific growth rate (SGR) and chlorophyll contents. Algal growth and SGR were inhibited on by effect of various concentrations of copper more than without copper (ANOVA, F=34.69 p<0.001, F=114.89, p<0.001). The SGRs of various concentrations of copper in media were higher than without copper on 8 days after copper treated. The mean of chlorophyll contents was 1.978 ${\mu}g{\cdot}mL^{-1}$ and 1.648 ${\mu}g{\cdot}mL^{-1}$, respectively, while those of algae in culture without copper was 3.179 ${\mu}g{\cdot}mL^{-1}$ (ANOVA, F=153.74, p<0.001). The cellular morphology was different between media of which copper treated and without copper. The colony of algae in media which copper treated was shorter than without copper. Effects of various concentrations of copper on growth change of blue-green-algae Anabaena flos-aquae occured variety changes of parameters of cell numbers, specific growth rate (SGR), chlorophyll contents and cellular morphology on growth of algae.

• Journal of Ginseng Research
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• 제40권4호
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• pp.453-461
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• 2016

Background: This study aims to describe the characterization of Paenibacillus polymyxa GBR-1 (GBR-1) with respect to its positive and negative effects on plants. Methods: The morphological characteristics of GBR-1 were identified with microscopy, and subjected to Biolog analysis for identification. Bacterial population and media optimization were determined by a growth curve. The potential for GBR-1 as a growth promoting agent, to have antagonistic activity, and to have hydrolytic activity at different temperatures was assessed. The coinoculation of GBR-1 with other microorganisms and its pathogenicity on various stored plants, including ginseng, were assessed. Results: Colony morphology, endospore-bearing cells, and cell division of GBR-1 were identified by microscopy; identification was performed by utilizing the Biolog system, gas chromatography of fatty acid methyl esters (GC-FAME). GBR-1 showed the strongest antagonistic activity against fungal and bacterial pathogens. GBR-1 cell numbers were relatively higher when the cells were cultured in brain heart infusion (BHI) medium when compared with other media. Furthermore, the starch-hydrolytic activity was influenced by GBR-1 at higher temperature compared to low temperatures. GBR-1 was pathogenic to some of the storage plants. Coinoculation of GBR-1 with other pathogens causes differences in rotting on ginseng roots. A significant growth promotion was observed in tobacco seedlings treated with GBR-1 suspensions under in vitro conditions, suggesting that its volatile organic compounds (VOCs) might play a role in growth promotion. Conclusion: The results of this study indicate that GBR-1 has both positive and negative effects on ginseng root and other stored plants as a potential biocontrol agent and eliciting in vitro growth promotion.

• Molecules and Cells
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• 제40권2호
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• pp.117-122
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• 2017

Despite the fact that porcine embryonic stem cells (ESCs) are a practical study tool, in vitro long-term maintenance of these cells is difficult in a two-dimensional (2D) microenvironment using cellular niche or extracellular matrix proteins. However, a three-dimensional (3D) microenvironment, similar to that enclosing the inner cell mass of the blastocyst, may improve in vitro maintenance of self-renewal. Accordingly, as a first step toward constructing a 3D microenvironment optimized to maintain porcine ESC self-renewal, we investigated different culture dimensions for porcine ICM-derived cells to enhance the maintenance of self-renewal. Porcine ICM-derived cells were cultured in agarose-based 3D hydrogel with self-renewal-friendly mechanics and in 2D culture plates with or without feeder cells. Subsequently, the effects of the 3D microenvironment on maintenance of self-renewal were identified by analyzing colony formation and morphology, alkaline phosphatase (AP) activity, and transcriptional and translational regulation of self-renewal-related genes. The 3D microenvironment using a 1.5% (w/v) agarose-based 3D hydrogel resulted in significantly more colonies with stereoscopic morphology, significantly improved AP activity, and increased protein expression of self-renewal-related genes compared to those in the 2D microenvironment. These results demonstrate that self-renewal of porcine ICM-derived cells can be maintained more effectively in a 3D microenvironment than in a 2D microenvironment. These results will help develop novel culture systems for ICM-derived cells derived from diverse species, which will contribute to stimulating basic and applicable studies related to ESCs.

• Archives of Pharmacal Research
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• 제23권1호
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• pp.79-86
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• 2000

Heterokaryotic nuclear hybrids overcoming the natural barriers of incompatibility have been studied in basidiomycetes. To produce these nuclear hybrids between incompatible mushrooms, which have several potent pharmacological effects, nuclear transfer was performed between Lentinula edodes and Coriolus versicolor. Nuclei from serine auxotrophs of Lentinula edodes, $LE207(Ser^{-})$ were transferred into the protoplasts of arginine auxotrophs of Coriolus versicolor, $CV17(Ser^{-})$using 30% polyethylene glycol 4000 in 10 mM $Cacl_{2}$-glycine solution (pH 8.0). Nulcear transfer progenies were selected by nutritional complementation on minimal media supplemented with 0.6 M sucrose. The progenies were classified based on colony morphology to L. edodes-like, C, versicolor-like and non-parental type. Most of the progenies grew slower than either parent. The number of nuclei per cell was similar but the DNA content varied between progenies. The isozyme patterns of nuclear hybrids resembled either of the parent porfiles or showed a mixed profile.

• 대한의생명과학회지
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• 제23권2호
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• pp.64-72
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• 2017

The formation of brown colonies due to phenol oxidase activity on classic agar media containing natural material extracts of Helianthus annuus or on medium containing L-3,4-dihydroxyphenylalanine has been used to identify Cryptococcus species complex. In this study, various natural materials were used to develop a modified medium and to identify five major serotypes of Cryptococcus species complex. Serotypes A, D, and A/D were pigmented on medium using Perilla frutescens var. japonica Hara (PerJ agar) after a three-day incubation. Serotypes B and C were pigmented on PerJ agar after four- and five-day incubations, respectively. Growth time and pigmentation of the five serotypes occurred more rapidly on PerJ agar than on the other media. In addition, colony morphology, size, and pigmentation were specific by serotype. In conclusion, PerJ agar should be used in clinic settings to identify Cryptococcus species complex and its serotypes rapidly.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.127.1-127
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• 2003

We describe two new Trichoderma species associated with oyster mushroom in Korea. Trichoderma green mould has been one of the most serious diseases of oyster mushroom in Korea. Of these the predominant species are two unrecorded species. We designed as Trichoderma sp. Korean type 1 (Th K1) and Trichoderma sp. Korean type 2 (Th K2), respectively. Th K1 and Th K2 can be distinguished from previously reported Trichoderma species as well as each other in morphological characteristics including growth rate at 35$^{\circ}C$, colony morphology, conidia shape and branch pattern of phialides. Sequence of the ITS region of rDNA, the protein coding translation elongation factor gene(EF-1${\alpha}$), and RNA polymeraseII (RPB2) not only clearly separated Trichoderma sp. Korean types from their closely related T. harzianum biotype but also distinguished them from each other. Analyses of the EF-1${\alpha}$ and RPB2 sequences were found to be more useful for establishing systematic relationships among Trichoderma isolates than those of the ITS sequence. Based on the results of morphological and molecular characteristics. We propose the two Trichoderma sp. Korean types as the new species

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.117.1-117
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• 2003

Phytophthora blight, caused by P. capsici, is very important disease of pepper. Many fungicides to control of Phytophthora blight have been developed, but most of fungicides disappeared in short periods. Nowadays dimethomorph was known as one of the most effective to control of this disease. P. capsici isolates from pepper fields were collected and surveyed their growth in dimethomorph amended V8 medium in order to evaluate their fungicides resistance. The fungicide resistant isolates were not founded among them. Most of the sensitive isolates were inhibited perfectly in V8 medium amended with 10ppm dimethomorph. Mutants of P. capsici by dimethomorph, was grown very well in 250ppm. The difference of pathogenicity, colony morphology, drug response, RT-PCR results was identified between sensitive and resistance isolates. This study should be provided a basic information about the occurrence of dimethomorph resistant isolates and genetic changes in P. capsici population.

• KSBB Journal
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• 제14권2호
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• pp.146-152
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• 1999

갈반병이 유발된 느티리버섯과 비섯 재배장 주변 토양에서 채집한 균주로부터 갈반병 원인균주 4개와 갈항균주 3개를 선발하였다- 선발된 균주를 API 2DE kit에 의해 동정한 결과 갈반병 원인 균주 P-24, P-28은 Pseudomonas putida로 P-27, P-33은 P.tolaasii로 동정되었으며, 길형균주 중 A-ll, A-20은 Pseudomonas fluorescence로 A-29는 Pseudοmonas sp.로 동정되었으며, 그 중 A-ll 균주가 버섯 균사 및 자실체에 해를 주지 않으면서 길항성이 우수한 균주로 선발되었다. 길항성은 갈반병 원인균 대 길항균의 농도비를 1:1로 처리하였을 때 길항성이 양호하였다.