• The Plant Pathology Journal
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• 제36권6호
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• pp.637-642
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• 2020

Fusarium wilt in tobacco caused by the fungus Fusarium oxysporum f. sp. nicotianae is a disease-management challenge worldwide, as there are few effective and environmentally benign chemical agents for its control. This challenge results in substantial losses in both the quality and yield of tobacco products. Based on an in vitro analysis of the effects of different phenylpropanoid intermediates, we found that the early intermediates trans-cinnamic acid and para-coumaric acid effectively inhibit the mycelial growth of F. oxysporum f. sp. nicotianae strain FW316F, whereas the downstream intermediates quercetin and caffeic acid exhibit no fungicidal properties. Therefore, our in vitro screen suggests that trans-cinnamic acid and para-coumaric acid are promising chemical agents and natural lead compounds for the suppression of F. oxysporum f. sp. nicotianae growth.

• 미생물학회지
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• 제54권4호
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• pp.420-427
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• 2018

효모균 타이로실-tRNA 합성효소(Sc YRS)와 엠버 멈춤코돈을 인식하는 대장균 시작tRNA 변이체(fMam $tRNA_{CUA}$)쌍은 대장균에서 단백질 생합성시 원하는 특정 위치에 비천연아미노산을 도입하는데 활용된다. Sc YRS/fMam $tRNA_{CUA}$쌍의 엠버써프레션 활성을 높이기 위해 fMam $tRNA_{CUA}$의 첫번째 안티코돈 염기를 인식하는 Sc YRS의 320번, 321번 아미노산 잔기를 암호화하는 염기서열을 무작위로 돌연변이시킨 라이브러리를 제작하였다. 엠버써프레션에 의한 클로람페니콜 저항성을 이용해 라이브러리를 탐색하여 활성이 향상된 2개의 돌연변이주를 선별하였다. 이들의 클로람페니콜 저항성 성장의 $IC_{50}$값은 야생형 YRS보다 1.7~2.3배 높았으며, in vivo 엠버써프레션 활성을 비교한 결과 3~6.5배의 활성 증가가 나타났다. 높은 활성을 보인 mYRS-3 (P320A/D321A) 단백질의 fMam $tRNA_{CUA}$에 대한 in vitro aminoacylation kinetics 분석은 야생형보다 약 7배 높은 효소활성을 보였으며, 이는 주로 기질인 fMam $tRNA_{CUA}$에 대한 결합 친화도가 증가하여 나타났다. 이런 접근법을 이용하여 다양한 종류의 비천연 아미노산 도입에 활용되는 aminoacyl-tRNA 합성효소의 엠버써프레션 활성을 높임으로써 엠버 멈춤코돈을 이용한 비천연 아미노산 도입 효율성을 높일 수 있을 것이다.

• 한국응용곤충학회지
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• 제23권1호
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• pp.22-27
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• 1984

오이를 재배했던 비닐하우스 토양에 병원균을 전면 접종하고 1983년 7월 25일부터 8월 25일까지 포리에칠렌 필림을 멀칭하여 태양열소독 효과를 실험하였다. 멀칭처리 기간중 토양의 일중 최고온도는 깊이 5cm에서 $58^{\circ}C$, 15cm는 $45^{\circ}C$, 25cm는 $42^{\circ}C$에 달했다. 태양열처리 한지 32일 경과후 지표로부터 5cm이내의 토양에 있던 병균은 완전히 사멸되었으며 15cm 까지는 $98\%$ 이상 소멸되었으나 25cm 토양은 무처리와 차이가 없었다. 그러나 태양열처리한 토양에서 분리한 균주는 무처리 토양의 균주보다 소형포자 생산량이 현저하게 감소되었다. 멀칭처리에 재배한 오이는 생육이 월등히 좋았는데 특히 5cm 이내의 토양에서 두드러지게 나타났으며 노지재배의 경우도 생장과 수량이 무처리에 비하여 현저히 좋았다. 병원균 F. oxysporum f. sp. cucumerinum은 오이 유균에 외관상 나타나는 병징 이외에도 전염원의 농도가 증가됨에 따라 오이 생육이 비례하여 억제됨을 나타내었다.

• 한국식물병리학회지
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• 제11권3호
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• pp.252-257
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• 1995

Growth rates of the low temperature growing isolates, Pseudomonas fluorescens M45 and MC07, reached maximum stationary phase within 50 hrs at the low temperature, 4$^{\circ}C$. But an ordinary biocontrol agent P. putida Pf3 did not reach logarithmic growth phase until 80 hrs. The culture filtrates of M45 and MC07 significantly inhibited the mycelial growths of Pythium ultimum, Rhizoctonia solani and Phytophthora capsici. Detached cotyledons of cucumber grown on Murashige and Skoog agar medium were much enhanced in their growth, compared to those without the filtrates. Population densities of M45 and MC07 in the rhizosphere at 14$^{\circ}C$ were more stable than at 27$^{\circ}C$. When M45 and MC07 were treated into soil, the population density of MC07 continuously increased up to 9 days after treatment, and sustained the initial inoculum density up to 60 days. Cucumber damping-offs caused by P. ultimum and R. solani were significantly reduced by applying M45 as seed-inoculant and by soil treatment with MC07. The combined treatment of M45 and MC07 provided greater effect in reducing the disease incidence than that obtained by single treatments.

• The Plant Pathology Journal
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• 제25권3호
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• pp.256-262
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• 2009

The potential of. nonpathogenic Fusarium oxysporum strain Avr5, either alone or in combination with chitosan and Bion, for inducing defense reaction in tomato plants inoculated with F. oxysporum f. sp lycopersici, was studied in vitro and glasshouse conditions. Application Bion at concentration of 5, 50, 100 and $500{\mu}g$/ml, and the highest concentration of chitosan reduced in vitro growth of the pathogen. Nonpathogenic F. oxysporum Avr5 reduced the disease severity of Fusarium wilt of tomato in split plants, significantly. Bion and chitosan applied on tomato seedlings at concentration $100{\mu}g$ a.i./plant; 15, 10 and 5 days before inoculation of pathogen. All treatments significantly reduced disease severity of Fusarium wilt of tomato relative to the infected control. The biggest disease reduction and increasing tomato growth belong to combination of nonpathogenic Fusarium and Bion. Growth rate of shoot and root markedly inhibited in tomato plants in response to tomato Fusarium wilt as compared with healthy control. These results suggest that reduction in disease incidence and promotion in growth parameters in tomato plants inoculated with nonpathogenic Fusarium and sprayed with elicitors could be related to the synergistic and cooperative effect between them, which lead to the induction and regulation of disease resistance. Combination of elicitors and non-pathogenic Fusarium synergistically inhibit the growth of pathogen and provide the first experimental support to the hypothesis that such synergy can contribute to enhanced fungal resistance in tomato. This chemical could provide a new approach for suppression of tomato Fusarium wilt, but its practical use needs further investigation.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2003년도 제10차 국제학술회의 및 추계정기 학술발표회
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• pp.47-47
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• 2003

Plant growth promoting rhizobacteria (PGPR) have been shown to suppress phytopthora blight. This suppression has been related to both microbial antagonism and induced resistance. The PGPR isolates were screened by dual culture plate method and most of the isolates were showed varyinglevels of antagonism. Among the PGPR isolates pyoverdin, pyochelin and salicylic acid producing strains showed the maximum inhibition of mycelial growth of Phytophthora capsici and increased plant growth promotion in red pepper. PGPR isolatesfurther analysed for its ability to induce production of defence related enzymes and chemicals. The activities such as Phenyle alanin ammonia lyase (PAL), Peroxidase (PO), Polyphenol oxidase (PPO) and accumulation of phenolics were observed in PGPR pretreated red pepper plants challenged with Phytophthora capsici. The present study shows that an addition of direct antagonism and plant growth promotion, induction of defense related enzymes involved to enhance resistance against invasion of P. capsici in red pepper.

• 대한임상검사과학회지
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• 제43권3호
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• pp.89-97
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• 2011

The Human Papilloma Virus (HPV) infection has been strongly associated with pathogenesis of uterine cervix carcinoma. HPV type 16, a causative agent of uterine cervix carcinoma, encodes the E6 and E7 oncogenes, expression of which is pivotal for malignant transformation and maintenance of malignant phenotypes. To develop a gene therapy for HPV-related carcinoma, We investigated the effect of E6 short-interfering RNA (E6 siRNA) on the expression of this oncogene and on the growth of HPV 16-related uterine cervix carcinoma cells. SiHa cells, a uterine cervix carcinoma cell line, which contain a single copy of HPV 16 integrated in the chromosome and express the E6 and E7 oncogenes. Before 24 hr of transfection, cells were seeded and transfected with control plasmid or E6 siRNA-expressing plasmid. The mRNA was analysed by reverse transcriptase polymerase chain reaction (RT-PCR). The cell growth rate was investigated by MTT method. The E6 mRNA level in SiHa cells was decreased in HPV 16 E6 siRNA-expression vector transfected cells and a decrease in the growth of these cells was also observed. From these results. it is evident that E6 siRNA played a role in suppression of growth of SiHa cells and has a fair chance as a candidate for gene specific therapy for HPV related uterine cervix carcinoma.

• 한국균학회지
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• 제24권1호통권76호
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• pp.38-48
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• 1996

유용 미생물로 선발한 Pseudomonas cepacia, Bacillus cereus 및 균근균을 인삼(Panax ginseng)근권에 처리한 후 이들 미생물들의 근권내 정착 및 근부병의 발생억제에 미치는 영향을 폿트 배양으로 실험하였다. P. cepacia의 단독 처리에서 처리 10일후에 근권에서 조사된 세균수는 6.26 (log cfu/g.soil)이나 B. cereus 등과 혼합 처리한 경우 $5.25{\sim}6.19(log\;cfu/g.soil)$으로 분포수가 적었고 처리기간이 270일 후에는 3.01 (log cfu/g. soil)으로 크게 감소하였다. Fusarium spp.의 근권내 분포수는 처리 $10{\sim}60$일 후에는 $3.33{\sim}3.67(log\;cfu/g.soil)$이었으나 처리 270일 경과 후에는 $3.33{\sim}1.02(log\;cfu/g.soil)$으로 크게 감소되었다. 근부병발생율에 있어서 대조가 4.3의 이병지수를 나타내나 P. cepacia 처리는 1.2로 발생이 크게 억제되었다. P. cepacia와 B. cereus의 혼합처리는 $1.8{\sim}2.3$의 이병지수로 대조 4.3보다는 병발생율이 낮아졌다. 균근균으로 Glomus albidum과 Acaulospora longular 처리는 병발생율 $1.2{\sim}1.6$으로 대조 4.3보다 감소하였다. 세균으로 P.cepacia와 균근균으로 G. albidum 처리는 근부율을 각각 1.2로 낮추는 발병억제 효과가 있다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2000년도 춘계 학술대회지
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• pp.232-233
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• 2000

• 한국분말재료학회지
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• 제19권2호
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• pp.127-133
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• 2012

The sintering behaviors and process parameters of some compounds (carbides, oxides, sulfides, borides) were investigated experimentally. These compounds were successfully consolidated and showed high densities. Some unique phenomena such as retardation of grain growth, suppression of thermal decomposition and maintenance of initial non-equilibrium phases, were observed by the proper control of process in spark sintering.