• The Plant Pathology Journal
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• 제22권2호
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• pp.119-124
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• 2006

Kudzu vine(Pueraria montana var. lobata) is an invasive climbing woody vine that envelops trees and shrubs, pressing physically and shutting out sunlight, which needs to be controlled. Kudzu vine pathogens were surveyed as a way to seek its biocontrol agents in 2002. Occurrence of a bacterial halo blight disease of kudzu vine was observed at several localities in Korea including Euiwang and Suwon in Gyeonggi Province, Daejon, and Gochang and Buan in Jeonbuk Province. Symptoms of brown to black spots with a surrounding yellowish halo appeared from June and lasted till the rainy season without much expansion, but accompanying often leaf blight and defoliation. Isolated bacteria were identified as Pseudomonas syringae pv. phaseolicola based on physiological and cultural characteristics, Biolog, fatty acid and 16S rDNA sequencing analyses. In artificial inoculation test, these bacteria produced the same halo spot symptoms on kudzu vine and bean plants. They also induced hypersensitive responses (HR) on tobacco, tomato, and chili pepper leaves. This is the first report of a bacterial disease of kudzu vine in Korea, and the bacterial pathogen can be used as a biocontrol agent against the pest plant.

• 식물병연구
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• 제8권4호
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• pp.250-253
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• 2002

참다래 궤양병의 간단하고 효율적인 병원성 검정법을 개발하고자 수행하였다. 이 검정법은 과민성반응(hypersensitive reaction) 검정법을 변형한 것으로 병원균을 50 mM 인산 완충액(pH 7.5)에 현탁하여 5년생 참다래 상위엽에 주사기를 이용하여 엽육세포에 주입하였다. 병징은 접종 2일 후부터 보이기 시작하여 4일후에 판정이 가능하였으며 검정한계 농도는 $10^4$cfu/ml이었다. 주사접종법을 이용하여 25종에 대한 기주범위를 검정하였을 때 병원균과 기주에 따라 여러 가지 병징을 보였다. 이 검정법은 습도와 관계없이 빠르게 병징을 나타내는 효과적인 방법이었다.

• 미생물학회지
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• 제44권1호
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• pp.1-9
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• 2008

본 논문은 벼 흰 잎마름병균인 Xanthomonas oryzae pv. oryzae(Xoo)의 병원성 유전자의 분자유전학적 연구현황을 기술하고자 한다. 또한 국내 고유 벼 흰 잎마름병균 KACC10331의 유전체해독 정보를 기반으로 다른 Xanthomonas의 유전체와 비교 분석함으로써, Xoo의 주요 병원성 유전자의 분자구조를 구명하고자 한다. 이를 통해 Xoo 고유 병원성 유전자 탐색 및 기능 해석을 위한 기초자료를 제공하는데 목적이 있다. Xoo 유전체에는 5개 과(family)에 속하는 9 type의 Insertion sequence(IS)가 611 copy로 존재하고 있으며, 주로 병원성 관련 유전자군 주위에 많이 분포하고 있는 것으로 나타났다. 현재까지 연구가 수행된 주요 병원성 관련 유전자인 hypersensitive response and pathogenicity (hrp) 유전자, extracellular polysaccharide (EPS) 유전자, extracellular enzyme 유전자, lipopolysaccharides (LPS) 유전자, 그리고 avilulence 유전자의 분자유전학적 연구현황을 기술하였다.

• The Plant Pathology Journal
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• 제18권3호
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• pp.115-120
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• 2002

Xanthomonas axonopodis pv. glycines, the causal agent of bacterial pustule of soybean, induces hypersensitive response (HR) in a non-host plant, hot pepper (Capsicum annuum). A wild-type strain (8ra) and its non-patho-genic mutant (8-13) of X. axonopodis pv. glycines were inoculated into the pepper leaf tissues and their subcellular responses to the bacterial infections were examined by electron microscopy. Intrastructural changes related to HR were found in the leaf tissues infected with 8ra from 8 h after inoculation, characterized by separation of plasmalemma from the cell wall, formation of small vacuoles and vesicles, formation of cell wall apposition, and cellular necrosis. No such responses were observed in the tissues infected with the mutant. In 8ra, the bacterial cells were attached to the cell walls, with the cell wall material dissolved into and appearing to encapsulate the bacterial cells. The bacterial cells later became entirely embedded in the cell wall material. On the other hand, in 8-13, the bacterial cells were usually not attached tightly to the plant cell wall, and no or poor encapsulation of the bacteria by the wall material occurred, although these were encircled by rather loose wall materials at the later stages.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2015년도 추계학술대회 및 정기총회
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• pp.26-26
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• 2015

Phytophthora infestans is the causal agent of potato and tomato late blight, one of the most devastating plant diseases. P. infestans secretes effector proteins that are both modulators and targets of host plant immunity. Among these are the so-called RXLR effectors that function inside plant cells and are characterized by a conserved motif following the N-terminal signal peptide. In contrast, the effector activity is encoded by the C terminal region that follows the RXLR domain. Recently, I performed in planta functional profiling of different RXLR effector alleles. These genes were amplified from a variety of P. infestans isolates and cloned into a Potato virus X (PVX) vector for transient in planta expression. I assayed for R-gene specific induction of hypersensitive cell death. The findings included the discovery of new effector with avirulence activity towards the Solanum bulbocastanum Rpi-blb2 resistance gene. The Rpi-blb2 encodes a protein with a putative CC-NBS-LRR (a coiled-coil-nucleotide binding site and leucine-rich repeat) motif that confers Phytophthora late blight disease resistance. We examined the components required for Rpi-blb2-mediated resistance to P. infestans in Nicotiana benthamiana. Virus-induced gene silencing was used to repress candidate genes in N. benthamiana and to assay against P. infestans infections. NbSGT1 was required for disease resistance to P. infestans and hypersensitive responses (HRs) triggered by co-expression of AVRblb2 and Rpi-blb2 in N. benthamiana. RAR1 and HSP90 did not affect disease resistance or HRs in Rpi-blb2-transgenic plants. To elucidate the role of salicylic acid (SA) in Rpi-blb2-mediated resistance, we analyzed the response of NahG-transgenic plants following P. infestans infection. The increased susceptibility of Rpi-blb2-transgenic plants in the NahG background correlated with reduced SA and SA glucoside levels. Furthermore, Rpi-blb2-mediated HR cell death was associated with $H_2O_2$, but not SA, accumulation. SA affects basal defense and Rpi-blb2-mediated resistance against P. infestans. These findings provide evidence about the roles of SGT1 and SA signaling in Rpi-blb2-mediated resistance against P. infestans.

• Molecules and Cells
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• 제19권3호
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• pp.418-427
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• 2005

When inoculated into sensitive tobacco Xanthi-nn plants, the crucifer and garlic-infecting Tobacco mosaic virus (TMV-Cg) induces local necrotic lesions that resemble those seen in the hypersensitive response (HR) of resistant tobacco plants. However, unlike these, tobacco Xanthi-nn plants do not become resistant to infection and the virus spreads systemically causing a severe disease characterized by necrotic lesions throughout the plant. To identify the viral protein that elicits this necrotic response, we used a set of hybrid viruses constructed by combination of TMV-Cg and the tobacco mosaic virus strain U1 (TMV-U1). In this study we present evidence that the coat protein of TMV-Cg (CPCg) is the elicitor of the necrotic response in tobacco Xanthi-nn plants. Local and systemic necrotic lesions induced by TMV-Cg and by the hybrid U1-CPCg -that carries CPCg in a TMV-U1 context- are characterized by cell death and by the presence of autoflorescent phenolic compounds and $H_2O_2$, just like the HR lesions. In addition, defense-related genes and detoxifying genes are induced in tobacco Xanthi-nn plants after TMV-Cg and U1-CPCg inoculation. We postulate that in our system, CPCg is recognized by sensitive tobacco plants that mount an incomplete defense response. We call this an HR-like since it is not enough to induce plant resistance.

• 대한화학회지
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• 제34권6호
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• pp.548-554
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• 1990

Eu(III)이온과 간단한 리간드 사이의 착물형성에 대한 온도와 리간드의 영향을 형광방출 스펙트럼을 이용하여 연구하였다. 온도와 리간드에 따라 hypersensitive 전이($^5D0\; {\to}\;^7F_2$)와 nonhypersensitive 전이($^5D0\; {\to}\;^7F_1$)의 상대적 세기는 온도와 리간드의 영향을 크게 받는다. 이러한 상대적 세기변화를 내부권 착물 형성에 의한 평형상수의 변화로 해석하여 $Eu(H_2O)_X^{3+}$ 에서 EuL(H$_2O)_{X-1}^{2+}$로의 내부권 착물 형성시의 열역학적 함수들을 계산하는데 사용하였다. EuCl(H$_2O)_{X-1}^{2+}$의 내부권 착물 형성시의 $\Delta{H}$는 대략 15 kJ/mol이고 온도에 따라 거의 영향을 받지 않는다. 그러나, EuNO$_3(H_2O)_{X-1}^{2+}$의 내부권 착물 형성시의 $\Delta{H}$는 온도에 따라 25$^{\circ}C$에서는 -11 kJ/mol 그리고 250$^{\circ}C$에서는 47 kJ/mol로 증가하였다.

• Journal of Periodontal and Implant Science
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• 제35권4호
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• pp.991-1002
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• 2005

The purpose of this study was to compare the effect of desensitizing agents applied on hypersensitive root surface following periodontal treatment. This study included 21 subjects(168 vital teeth). To evaluate dentin sensitivity, three clinical tests(tactile, air stream, cold water) were tried and three different densensitizing agents(MS coat, Elmex gel. Superseal) were individually applied. After application, reassessment was done at 1 minute, 1 week, 1 month and 3 months. The results were as follows : 1. The degree of dentin sensitivity was measured highly in the sequence of cold water, air stream and tactile and significantly decreased in all four groups with lapse of time(p<0.05). 2. There was no significant difference between all four groups in the tactile test with lapse of time. 3. There was no significant difference between three experimental groups in the air stream test with lapse of time. however, one minute later, it was measured highly in the sequence of Superseal, MS coat and Elmex 4. There was no significant difference between three experimental groups in the cold water test with lapse of time. As a result of this study, all of three agents were significantly effective in reducing dentin hypersensitivity and these agents could be positively employed to patients complaining of dentin hypersensitivity following periodontal treatment.

• 대한화학회지
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• 제36권6호
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• pp.824-831
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• 1992

수용액에서 Ho(III) 이온과 간단한 리간드 사이의 착물 형성에 대한 온도와 리간드 농도의 영향을 흡수 스펙트럼을 이용하여 연구하였다. Hypersensitive 전이$(^5I_8\;\to\;^5G_6)$의 전이세기 변화는 온도와 리간드의 영향을 크게 받고, 이 변화는 Ho(Ⅲ) 이온의 배위 환경 변화로 해석될 수 있다. 이 스펙트럼에서 관찰된 전이세기를 분석하여 Judd-Ofelt 전이세기 파라미터($\Omega_\lambda$, $\lambda$ = 2, 4, 6)를 구했다. 이 파라미터들 중 $\Omega_2$ 파라미터가 온도와 리간드에 의해 가장 큰 변화를 보이고, 이 변화로부터 $Cl^-$와 ${NO_3}^-$가 수용액에서 내부권 착물을 형성함을 보였다

• 대한약침학회지
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• 제9권2호
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• pp.79-86
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• 2006

Objectives : The aim of this study was to observe prevention of allergic reactions of Sweet Bee Venom (removing enzyme components from Bee Venom). Methods: Content analysis of Sweet Bee Venom and Bee Venom was rendered using HPLC method and characterization of Anti-Sweet Bee Venom in Rabbit Serum. Clinical observation was conducted for inducement of allergic responses to Sweet BV. Results : 1. Analyzing melittin content using HPLC, Sweet BV contained 34.9% more melittin than Bee venom pharmacopuncture at same concentration. 2. Observing chromatogram of HPLC, removal of the enzyme was successfully rendered on Sweet BV. 3. The anti-serum of Sweet BV showed high titers against melittin and bee venom and relatively low titer against phospholipase A2. 4. After conducting approximately 3,000 cases of Sweet BV administration, not a single case of generalized anaphylatic reaction occurred in clinical observation. 5. Mild compared to the bee venom pharmacopuncture, Sweet BV showed some acute hypersensitive reactions of edema, itchiness, and aching locally. 6. Sweet BV was administered on six patients with previous history of suffering from generalized acute hypersensitive reactions with the bee venom. None of the patients showed allergic reactions with Sweet BV, suggesting it can effectively prevent anaphylatic shock which may occur after the bee venom pharmacopuncture procedure. Conclusion : Summarizing above results, Sweet Bee Venom appears to be an effective measurement against allergic reactions from the bee venom pharmacopuncture especially against anaphylatic shock.