• Mycobiology
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• 제46권4호
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• pp.429-439
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• 2018

To develop a convenient promoter analysis system for fungi, a null-pigment mutant (NPG) of Aspergillus nidulans was used with the 4'-phosphopantetheinyl transferase (PPTase) gene, npgA, which restores the normal pigmentation in A. nidulans, as a new reporter gene. The functional organization of serially deleted promoter regions of the A. nidulans trpC gene and the Cryphonectria parasitica crp gene in filamentous fungi was representatively investigated to establish a novel fungal promoter assay system that depends on color complementation of the NPG mutant with the PPTase npgA gene. Several promoter regions of the trpC and crp genes were fused to the npgA gene containing the 1,034-bp open reading frame and the 966-bp 3' downstream region from the TAA, and the constructed fusions were introduced into the NPG mutant in A. nidulans to evaluate color recovery due to the transcriptional activity of the sequence elements. Serial deletion of the trpC and crp promoter regions in this PPTase reporter assay system reaffirmed results in previous reports by using the fungal transformation step without a laborious verification process. This approach suggests a more rapid and convenient system than conventional analyses for fungal gene expression studies.

• 한국식물병리학회지
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• 제14권4호
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• pp.345-349
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• 1998

Fifty isolates of myxobacteria were isolated from soils from several areas in Korea during 1996-1997 and bioactivity against plant pathogenic fungi of these isolates was examined. A myxobacterial isolate KR025 showed good antifungal activities against Pyricularia oryzae, Cryphonectria parasitica, Colletotrichum lagenarium, and C. gloeosporioides but did not against Rhizoctonia solani, Fusarium oxysporum and Pythium ultimum. The bacterium was identified as Myxococcus fulvus based on morphological and physiological characteristics. Antifungal substances were extracted from culture broth and bacterial cell of Myxococcus fulvus KR025 by ethyl acetate. Antifungal substance of Myxothiazole (100 ${\mu}{\textrm}{m}$/ml) produced by Myxococcus fulvus KR 025 controlled 97.0% rice blast, tomato late blight, wheat leaf rust, and barley powdery mildew and showed 45.0 and 82.6% disease control of rice sheath blight and cucumber gray model, respectively.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2022년도 추계학술대회
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• pp.30-30
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• 2022

Natural products decursin and decursinol angelate were recently reported as benign fungicides for controlling rice blast. Inspired by the structural similarity of the cumarin compounds and gained hint from the skeletal motifs, we designed and prepared synthetic compounds to increase the natural product efficacy and evaluated their antifungal activities against various plant disease pathogens in vitro. Synthetically prepared compound 4 and 5 indeed suppressed the mycelial growth of B. cinerea, F. oxysporum, P. italicum, and R. quercus-mongolicae. Additionally, compound 5 effectively prevents the growth of C. coccodes and C. parasitica. Furthermore, both 4 and 5 possess better inhibitory activities on spore germination of F. oxysporum and M. oryzae than the natural product decursin. These results suggest that the effect of the lead compound for plant disease protection can be improved by tuning the structure of the original natural product and decursinol chloroacrylates 4 and 5 are candidates for the control of F. oxysporum and M. oryzae.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2022년도 추계학술대회
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• pp.98-98
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• 2022

Natural products decursin and decursinol angelate were recently reported as benign fungicides for controlling rice blast. Inspired by the structural similarity of the cumarin compounds and gained hint from the skeletal motifs, we designed and prepared synthetic compounds to increase the natural product efficacy and evaluated their antifungal activities against various plant disease pathogens in vitro. Synthetically prepared compound 4 and 5 indeed suppressed the mycelial growth of B. cinerea, F. oxysporum, P. italicum, and R. quercus-mongolicae. Additionally, compound 5 effectively prevents the growth of C. coccodes and C. parasitica. Furthermore, both 4 and 5 possess better inhibitory activities on spore germination of F. oxysporum and M. oryzae than the natural product decursin. These results suggest that the effect of the lead compound for plant disease protection can be improved by tuning the structure of the original natural product and decursinol chloroacrylates 4 and 5 are candidates for the control of F. oxysporum and M. oryzae.

• 한국작물학회지
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• 제29권1호
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• pp.67-71
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• 1984

참깨의 주요병해인 역병에 대한 품종선발시험과 엽고병에 대한 발병조건을 구명하기 위하여 포장과 온실을 이용하여 시험을 실시한 결과 다음과 같은 중요 사항이 관찰되었다. 1. 역병에 대한 저항성품종은 Orotall. Suweon 7, Suweon 27 및 조치원이 저항성 품종으로 나타났고 PI 280795, IS 103도 다소 강한 품종으로 보였다. 2. 참깨 엽고병예 대한 발병률은 고온인 3$0^{\circ}C$에서 광의품종이 15%, 김포품종이 25%의 병반면적률을 보였고, 저온인 17$^{\circ}C$에서는 광의가 50%, 김포가 70%로 높은 이병성을 보였다. 3. 참깨 엽고병의 발병률은 다습조건에서 품종 광의가 55%, 김포가 80%의 병반면적률을 보였고. 건조조건에서는 광의와 김포품종이 각각 10%와 15%의 병반면적률을 보임으로서 다습조건에서 심한 발병현상을 보였다. 4. 엽령별 엽고병 발병정도를 보면 6엽기와 개화기에 각각 20%와 52.5%의 병반면적률을 보여 심한 발병현상을 보였고, 10엽기와 20엽기에는 이보다도 낮은 발병률을 보였다.

• 한국버섯학회지
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• 제8권2호
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• pp.41-50
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• 2010

Mycoviruses have been found in many fungal species including mushrooms. Double-stranded (ds) RNA genomes were common type in mycoviruses, but single-stranded (ss) RNA mycoviruses were also reported in some fungal species. Sequencing analysis using cDNA cloning experiments revealed that mycoviruses can be classified into several different virus families such as Totiviridae, Hypoviridae, Partitiviridae and Barnaviridae etc. Because the nucleotide sequence data that are available in these days are very limited in a number of mycoviruses, the existence of more diverse viral groups in fungi are currently expected. In this review, we selected four different fungal groups, which were considered as the model systems for mycovirus related studies in both plant pathogenic fungi and edible mushroom species, and discussed about their molecular characteristics of diverse mycoviruses. The plant pathogenic fungi introduced here were Cryphonectria parasitica and Helminthosporium victoriae and the edible mushroom species were Agaricus bisporus and Pleurotus ostreatus.

• 한국식물병리학회지
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• 제14권5호
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• pp.445-451
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• 1998

A severe Phytophthora rot of strawberry caused by a species of Phytophthora has been widely occurred at major cultivation areas of Kimhae on August in 1997. Incidence of the disease was obtained in the range of 69.2~83.6% in surveyed 4 fields and showed an average of 75.2%. A species of Phytophthora was mostly isolated from the crown of infected strawberry plants and all the isolates were identified as P. nicotianae var. nicotianae (=P. parasitica). The fungus showed strong pathogenicity on strawberry by inoculation test. As a result of the leaf inoculation using mycelial disks of the fungus, both leaves and petioles were darkly browned, and were finally blighted. As a result of the root inoculation of zoospore suspension, both roots and crowns were rotten with dark brown. Although the fungus produced sporangia either on V-8 juice agar medium or liquid medium, the sporangia observed on the liquid medium appeared to be broadly turbinate and noncaducous. Moreover the fungus cultured on the liquid medium often produced sporangia having two papilla. The number of zoospores in sporangia was found to be ranged from 3 or 4 to as many as 20 or 25. In addition, the released zoospore from the sporangium became the cystospore during the prolonged culture of the fungus. The sporangia were measured as av. 49$\times$35 ${\mu}{\textrm}{m}$ with l/b ratio of 1.43. All isolates from crowns were heterothallic and A1 mating type since oospores were abundantly formed on clarified V-8 juice agar by dual culture with P. capsici A2 mating type. Aplerotic oospores were sized 24-26 ${\mu}{\textrm}{m}$. Antheridia were always amphigynous and recoreded an average of 12$\times$10 ${\mu}{\textrm}{m}$. Hyphal swlling were easily observed, and terminal or intercalary chlamydospores were abundantly formed on V-8 juice agar as well as in C/Z solution and sized av. 28.2 ${\mu}{\textrm}{m}$. This is the first report of Phytophthora rot of strawberry in Korea.

• Journal of Plant Biotechnology
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• 제38권1호
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• pp.54-61
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• 2011

에틸렌 생합성 효소인 ACC oxidase 유전자인 CAO cDNA가 antisense 방향으로 도입된 형질전환 담배 식물체는 endogenous한 NtACO의 발현 및 에틸렌 생합성이 모두 억제되었다. 또한 폴리아민 생합성 효소인 SAMDC의 유전자 발현 및 효소 활성이 증가하였고 spermidine 함량이 증가하였다. 이러한 결과는 에틸렌 생합성의 감소로 인하여 세포 내 폴리아민 함량의 변화가 유도되는 경쟁적 관계로 spermidine이 증가하였고 이것은 SAMDC의 발현 및 활성 증가를 유도하였다고 여겨진다. 또한 이들 형질전환 식물체는 담배 역병균에 대한 저항 효과 뿐만 아니라 PR 단백질의 유전자들의 발현양이 증가하였는데 이는 에틸렌 감소에 유도되는 폴리아민 중에서도 spermidine의 증가가 PR 단백질의 유전자들의 발현을 촉진시키고 그 결과 병원균 감염에 대한 저항성을 유도하는 기작이 작동한 것으로 여겨진다. Spermidine을 합성하는데 중요하게 작용하는 SAMDC의 활성을 억제하는 MGBG를 처리한 경우에는 PR1a 발현이 억제된 경우에서 이 기작의 가능성을 확인하였다. 결론적으로 병원균 감염에 대한 과정에서 spermidine의 생합성이 증가하게 되면 PR 단백질 등 스트레스 저항성 관련 단백질들이 유도되어 스트레스 저항성을 높일 수 있을 것으로 사료된다.

• 한국잡초학회지
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• 제14권1호
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• pp.16-22
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• 1994

경기도 광주군 및 연천군 일원에서 채취한 93종의 잡초종(雜草種)을 대상으로 항균활성(抗園活性), 항종양활성(抗腫瘍活性), 항산화활성(抗酸化活性), 제초활성(除草活性) 등 몇가지 생리활성(生理活性)을 조사함으로써 제초(雜草)의 유용적(有用的)인 측면(則面)의 확인 뿐 아니라 나아가서 잡초(雜草)로부터 새로운 생리활성물질탐색(生理活性物質探索)의 가능성(可能性)을 제시하고자 하였다. 곰팡이에 있어서 사과나무 점무늬낙엽병균(落葉病菌)에 대해서는 새삼, 고추 역병균(疫病菌)에 대해서는 돼지풀과 쥐손이풀, 참깨 역병균(疫病菌)에 대해서는 쑥부쟁이와 미국쑥부쟁이가 항균활성(抗菌活性)을 나타내었다. 세균에 있어서는 돼지풀, 쑥, 사철쑥, 여뀌바늘, 구절초, 쥐손이풀, 미국가막사리 등이 비교적 항균활성(抗菌活性)의 범위(範圍)가 넓었으며 개비름, 비름, 망초, 물질경이, 쇠무릎, 물봉선, 벼룩나물 등이 Gram 양성세균인 Bacillus subtilis PCI219에 대하여 선택적(選擇的)인 항균활성(抗菌活性)을 나타내었다. 그리고 새삼, 개가장, 갈대, 쉽사리, 기름나물 등이 세포벽(細胞壁) 결손(缺損) 변이주(變異洙)인 Pseudomonas aeruginosa N10 균주에 대하여 선택적(選擇的)인 항균활성(抗菌活性)을 나타내었다. K562 세포(細胞)에 대한 protein kinase C 활성(活性)으로 조사한 antibleb 활성(活性)은 큰개여뀌, 사철쑥, 국화방망이, 개가장, 쥐손이풀, 바늘사초 등에서 나타났으며 특히 큰개여뀌에서는 조시료(粗試料) 상태에서 10mg/ml 농도(濃度)에서도 강한 활성(活性)을 나타내었다. 항산화활성(抗酸化活性)에 있어서는 바디나물, 쇠뜨기, 승마, 큰개여뀌, 쥐손이풀, 달맞이꽃, 방동사니대가리 등이 비교적 강한 활성(活性을) 나타내었으며 제초활성(除草活性)에 있어서는 여뀌바늘, 기름나물 등이 비교적 강한 활성(活性)을 나타내었다.