• Mycobiology
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• 제32권1호
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• pp.47-53
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• 2004

Pseudomonas fluorescens 1-94 induced systemic resistance in chickpea against Fusarium wilt of chickpea caused by Fusarium oxysporum f. sp. ciceri by the synthesis and accumulation of phenolic compounds, phenylalanine ammonia lyase(PAL) and pathogenesis related(PR) proteins(chitinase, $\beta$-1,3-glucanase and peroxidase). Time-course accumulation of these enzymes in chickpea plants inoculated with P. fluorescens was significantly(LSD, P=0.05) higher than control. Maximum activities of PR-proteins were recorded at 3 days after inoculation in all induced plants; thereafter, the activity decreased progressively. Five PR peroxidases detected in induced chickpea plants. Molecular mass of these purified peroxidases was 20, 29, 43, 66 and 97 kDa. Purified peroxidases showed antifungal activity against plant pathogenic fungi.

• Natural Product Sciences
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• 제21권1호
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• pp.54-58
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• 2015

The protective effect of EtOAc fraction of Limonium tetragonum extract (EALT) against alcohol-induced hepatotoxicity was assessed following acute ethanol intoxication in Spraque-Dawley rats. EALT (200 mg/kg p.o.) was administrated once before alcohol intake (8 g/kg, p.o.). Blood ethanol concentration, and the activities of alcohol metabolic enzymes, alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) in the liver were measured. Also, the formation of malondialdehyde (MDA) and the activities of antioxidant enzymes, superoxide dismutase (SOD), glutathione peroxidase (GSH-px), catalase were determined after acute alcohol exposure. Pretreatment of rats received ethanol with EALT significantly decreased blood ethanol concentration and elevated the activities of ADH and ALDH in liver. The increased MDA level was decreased, and the reduced activities of SOD, GSH-px and catalase were markedly preserved by the treatment with EALT. This study suggests that EALT prevent hepatic injury induced by acute alcohol which is likely related to its modulation on the alcohol metabolism and antioxidant enzymes activities.

• Journal of Microbiology and Biotechnology
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• 제22권8호
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• pp.1118-1126
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• 2012

Four putative GH12 genes were found in the Fusarium graminearum genome. The corresponding proteins were expressed in Escherichia coli, purified, and evaluated. FGSG_05851 and FGSG_11037 displayed high activities towards xyloglucan ($V_{max}$ of 4 and $11{\mu}mol/min$, respectively), whereas FGSG_07892 and FGSG_16349 were much less active with this substrate (0.081 and $0.004{\mu}mol/min$, respectively). However, all four of these enzymes had a similar binding affinity for xyloglucan. Xyloglucan was the substrate preferred by FGSG_05851, in contrast to the three other enzymes, which preferred ${\beta}$-glucan or lichenan. Therefore, FGSG_05851 is a xyloglucan-specific glucanase (E.C. 3.2.1.151) rather than an endoglucanase (E.C. 3.2.1.4) with broad substrate specificity. FGSG_11037 displayed a peculiar behavior in that the xyloglucan binding was highly cooperative, with a Hill coefficient of 2.5. Finally, FGSG_05851 essentially degraded xyloglucan into hepta-, octa-, and nonasaccharides, whereas the three other enzymes yielded hepta- and octa-saccharides as well as larger molecules.

• 동의생리병리학회지
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• 제22권3호
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• pp.569-574
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• 2008

The GUE6 was isolated from ethyl acetate fraction of Glycyrrhiza uralensis and confirmed as liquiritin. Liquiritin(LQ) treated with ${\beta}$-glucosidase from plant(Prunus dulcis) and bacteria(Lactobacillus pentosus) crude enzymes. The ${\beta}$-glucosidase activities of crude enzymes were 229.8 U/g(Prunus dulcis) and 19.17 U/ml(Lactobacillus pentosus), respectively. Liquiritin(LQ) biotransformed into liquiritigenin(LQG) by ${\beta}$-glucosidase from crude enzymes. The EtOAc fraction(GUE6) and the converted product were identified as liquiritin and liquiritigenin, by TLC chromatogram, $^{1}H$-NMR and $^{13}C$-NMR.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2018년도 춘계학술대회 및 임시총회
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• pp.19-19
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• 2018

Fungal pathogens have huge impact on health and economic wellbeing of human by causing life-threatening mycoses in immune-compromised patients or by destroying crop plants. A key determinant of fungal pathogenesis is their ability to undergo developmental change in response to host or environmental factors. Genetic pathways that regulate such morphological transitions and adaptation are therefore extensively studied during the last few decades. Given that epigenetic as well as genetic components play pivotal roles in development of plants and mammals, contribution of microbial epigenetic counterparts to this morphogenetic process is intriguing yet nearly unappreciated question to date. To bridge this gap in our knowledge, we set out to investigate histone modifications among epigenetic mechanisms that possibly regulate fungal adaptation and processes involved in pathogenesis of a model plant pathogenic fungus, Magnaporthe oryzae. For functional and comparative analysis of histone modifications, a web-based database (dbHiMo) was constructed first to archive and analyze histone modifying enzymes from eukaryotic species whose genome sequences are available. Based on the database entries, we carried out functional analysis of genes encoding histone modifying enzymes. Here I provide examples of such analyses that show how histone acetylation and methylation is implicated in regulating important aspects of fungal pathogenesis. Current analysis of histone modifying enzymes is followed by ChIP-seq and RNA-seq experiments to pinpoint the genes that are controlled by particular histone modifications. We anticipate that our work will provide not only the significant advances in our understanding of epigenetic mechanisms operating in microbial eukaryotes but also basis to expand our perspective on regulation of development in fungal pathogens.

• The Plant Pathology Journal
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• 제38권1호
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• pp.12-24
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• 2022

In this study, we conducted whole-genome sequencing with six species of Pectobacterium composed of seven strains, JR1.1, BP201601.1, JK2.1, HNP201719, MYP201603, PZ1, and HC, for the analysis of pathogenic factors associated with the genome of Pectobacterium. The genome sizes ranged from 4,724,337 bp to 5,208,618 bp, with the GC content ranging from 50.4% to 52.3%. The average nucleotide identity was 98% among the two Pectobacterium species and ranged from 88% to 96% among the remaining six species. A similar distribution was observed in the carbohydrate-active enzymes (CAZymes) class and extracellular plant cell wall degrading enzymes (PCWDEs). HC showed the highest number of enzymes in CAZymes and the lowest number in the extracellular PCWDEs. Six strains showed four subsets, and HC demonstrated three subsets, except hasDEF, in type I secretion system, while the type II secretion system of the seven strains was conserved. Components of human pathogens, such as Salmonella pathogenicity island 1 type type III secretion system (T3SS) and effectors, were identified in PZ1; T3SSa was not identified in HC. Two putative effectors, including hrpK, were identified in seven strains along with dspEF. We also identified 13 structural genes, six regulator genes, and five accessory genes in the type VI secretion system (T6SS) gene cluster of six Pectobacterium species, along with the loss of T6SS in PZ1. HC had two subsets, and JK2.1 had three subsets of T6SS. With the GxSxG motif, the phospholipase A gene did locate among tssID and duf4123 genes in the T6SSa cluster of all strains. Important domains were identified in the vgrG/paar islands, including duf4123, duf2235, vrr-nuc, and duf3396.

• 한국자원식물학회지
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• 제28권5호
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• pp.600-607
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• 2015

본 연구는 우슬과 골쇄보 활용하여 in vitro와 in vivo에 대한 실험으로 진행 되었다. 이 두 가지 약용작물을 추출하고 골다공증을 예방하는 능력을 연구하였다. 연구재료로 사용 된 시료는 증류수를 사용하여 추출 후 동결건조 하였다. 시료는 다시 다이메틸설폭사이드에 녹여서 사용 하였다. in vitro실험의 스텐다드 프로토콜에 맞추어 DPPH 라디칼 소거능, 환원력, 총항산화력, SOD 유사활성 그리고 Fe²⁺chelate활성을 측정 하였다. In vivo동물 실험에서는 난소를 제거한 스프레그다우리 쥐를 4개의 식이요법그룹으로 무작위로 나누었다. SHAM: 모의처치 대조군, OVX: 난소를 제거한 후 일반 식이를 먹인 쥐, OVX-AR: 난소를 제거한 후 우슬을 먹인 쥐, OVX- DR; 난소를 제거한 후 골쇄보를 먹인 쥐, 사용하였으며 그리고 8주 동안 실험 식이를 먹인 후 혈장 및 적혈구 TBARS 농도와 SOD, GSH-Px, GR, CAT 활성도를 측정하였다. in vitro항산화 활성 분석 결과를 보면 양성 대조군이 1% Vitamin C 용액이 94%정도의 DPPH 라디칼 소거능을 보였으며 우슬과 골쇄보 추출물에 대한 DPPH 값은 골쇄보의 값이 우슬보다 유의적으로 높은 소거능을 보였다. 환원력에서도 골쇄보가 우슬보다 유의적으로 높은 높은 값을 보였다. 반면에 총 항산화력에서는 우슬이 골쇄보다 유의적으로 높은 항산화력을 나타내었다. SOD의 측정값은 우슬과 골쇄보 간에 유의적 차이가 없었다. Fe²⁺ chelate활성에선 DPPH와 환원력과 달리 우슬이 77.60%로 골쇄보 46.21%에 비해 유의적으로 높은 활성도를 나타내었다. 혈장 TBARS 농도는 우슬 추출물을 섭취한 OVX-AR군이 13.58 ± 0.20 (nmol/㎖)로 SHAM군의 15.70 ± 0.20와 비슷한 수준으로 낮았고, 난소 제거 후 일반 식이를 먹인 OVX군이 20.70 ± 0.08로 유의적으로 가장 높은 수치를 나타 내어 과산화 지질 함량이 가장 높았다. 간 조직 항산화효소 활성을 보면 OVX- AR군(우슬)이 GSH-Px, PON에서 유의적으로 높은 활성을 보였고 CAT와 GR에서 OVX-DR군(골쇄보)이 유의적으로 높게 났다. 신장 조직 항산화 효소 활성에서는 OVX- DR군(골쇄보) 이 SOD, GSH-Px, GR, PON 에서 유의적으로 높게 나타났으며, 자원 추출물 간의 CAT 활성도의 유의적인 차이는 없었다. 적혈구 항산화 효소 활성은 SOD에서 OVX-DR군(골쇄보)이, GSH- Px에서는 OVX-AR 군(우슬)이 유의적으로 높았고, CAT와 GR 활성은 난소절제 후 OVX(자원식물 추출)군이 SHAM(일반식이 투여)군 보다 유의적으로 높은 항산화효소 활성을 보여 주었다.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.94.2-95
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• 2003

E. intermedium 60-2G possessing a strong ability to solubilize insoluble phosphate, has plant growth-promoting activity, induced systemic resistance activity against scab pathogen in cucumber, and antifungal activity against various phytopathogenic fungi. The phosphate solubilizing activity of 60-2G may be mainly accomplished by production of gluconic acid through a direct extracellular oxidation of glucose by glucose dehydrogenase that required a PQQ cofactor for its activation. A pqq gene cluster conferred Phosphate-solubilizing activity in E. coli DH5${\alpha}$ was cloned and sequenced. The 6,783 bP pqq sequence had six open reading frames (from A to F) and showed 50-95％ homology to pqq genes from other bacteria. The E. coli strain expressing the pqq genes solubilized phosphate from hydroxyapatite after a pH drop to 4.0, which paralleled in time the secretion of gluconic acid. To study the role of PQQ in biocontrol traits of E. intermedium, PQQ mutants of 60-2G were constructed by marker exchangee mutagenesis. The PQQ mutants of E. intermedium were lost activities of solubilizing phosphate, growth inhibition of phytopathogenic fungi, and plant growth promotion. These findings suggest that PQQ plays an important role, possibly activation of certain enzymes, in several beneficial bacterial traits of E. intermedium by as yet an unknown mechanism.

• Asian-Australasian Journal of Animal Sciences
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• 제12권1호
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• pp.93-103
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• 1999

Recent advances in the biotechnology of ruminal bacteria have been made in the characterization of enzymes involved in plant cell wall digestion, the exploration of mechanisms of gene transfer in ruminal bacteria, and the development of vectors. These studies have culminated in the introduction and expression of heterologous glucanase and xylanase genes and a fluoroacetate dehalogenase gene in ruminal bacteria. These recent studies show the strategy of gene and vector construction necessary for the production of genetically engineered bacteria for introduction into ruminants. Molecular research on proteolytic turnover of protein in the rumen is in its infancy, but a novel protein high in essential amino acids designed for intracellular expression in ruminal organisms provides an interesting approach for improving the amino acid profile of ruminal organisms.

• 환경위생공학
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• 제22권3호
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• pp.27-33
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• 2007

M. incognita are plant-parasite nematode that cause severe damage to the crops. P. lilacinus are renowned for inhibitation of development of M. incognita's egg. We make a study for enzymatic examining the cause closely that P. lilacinus suppress development of M. incognita's egg by parasiting. The research result is explained the place below. 1. The egg that is exposed to co-enzymes which are cultured in the broth culture starts to change the membrane of egg from 3days. And in 10days, that membrane completely disappear. These are observed through light microscope. Therefore, we know that M. incongnita are controlled by extracellular lytic enzymes that are produced by P. lilacinus. 2. Through scanning electron microscope, we can find that the egg that is attacked by P. lilacinus loses it's membrane gradually, and that loss of the membrane causes transform, which suppresses the development of egg.