• Mycobiology
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• 제36권1호
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• pp.19-23
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• 2008

Red pepper (Capsicum annum L.) roots and soils representing different agricultural management practices such as conventional (CON), no-chemical (NOC), and organic farming systems (ORG) were collected from 32 farm field sites in Kyunggi, Korea to investigate the effects of these agricultural practices on arbuscular mycorrhizal (AM) symbiosis. ORG inoculum significantly increased plant growth compared to inoculum from CON and NOC. A community analysis of AM fungi (AMF) using morphological features of spores revealed that AMF spore abundance and species diversity were significantly higher in ORG than in CON. Additionally, a community analysis of AMF colonizing roots using a molecular technique revealed higher AMF diversity in ORG than in CON. These results suggest that agricultural practices significantly influence AM fungal community structure and mycorrhizal inoculum potential.

• 약학회지
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• 제47권5호
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• pp.293-299
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• 2003

Structure-activity relationship studies of allylamine type of antimycotics were carried out to evaluate the effect of naphthyl and methyl portion of naftifine. Compounds with 4-fluorophenyl(2a-5a), 2-fluorophenyl(2b-5b), 2,4-dichlorophenyl(2c-5c), 2,6-dichlorophenyl(2d-5d), 4-nitrophenyl(2e-5e), and 2,3-dihydro-benzo[1,4]dioxan-6-yl( 2f-5f) instead of naphthyl group with hydrogen(3a-3f), methyl(4a-4f), and ethyl(5a-5f) in the place of methyl in naftifine were synthesized and tested their in vitro anti-fungal activity against five different fungi. Eight compounds(3a, 5a, 3c, 4c, 4d, 5d, 5e, and 4f) showed significant antifungal activity against T. mentagrophytes. (E)-N-Ethyl-(3-phenyl-2-propenyl)-4-nitro-benzenemethaneamine(5e) displayed moderate antifungal activity against all five different fungi.

• International Journal of Industrial Entomology and Biomaterials
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• 제9권2호
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• pp.229-234
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• 2004

Six entomopathogenic fungus isolates, Beauveria bassiana J57A, Nomuraea rileyi J125A, Paecilomyces farinosus J3A, Paecilomyces fumosoroseus J50A, Metarhizium anisopliae J88, Aspergilius sp. J64A, causing muscardine disease and aspergillosis in the silkworm, Bombyx mori were investigated for their cultural and morphological characteristics (on PDA culture media within 14 days at $24^{\circ}C$). The results showed that they differ each other from the features of cultural characteristics (colony elevation, colony color, colony growth rate) or morphological characteristics (conidiogenous cell structure, phialides, conidia size and shape). Among cultural characteristics, colony color is the easiest recognizable character between isolates. The morphological characteristics of each fungal isolate correspond to the descriptions of current system of classification.

• Mycobiology
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• 제37권4호
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• pp.272-276
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• 2009

In this study, eight soil samples were collected from organic and conventional farms in a central area of South Korea. Spore communities of arbuscular mycorrhizal fungi (AMF) and glomalin, a glycoprotein produced by AMF, were analyzed. Spores of Glomus clarum, G. etunicatum, G. mosseae, G. sp., Acaulospora longula, A. spinosa, Gigaspora margarita, and Paraglomus occultum were identified at the study sites, based on morphological and molecular characteristics. While Acaulospora longula was the most dominant species in soils at organic farms, Paraglomus occultum was the most dominant species in soils at conventional farms. Species diversity and species number in AMF communities found in soils from organic farms were significantly higher than in soils from conventional farms. Glomalin was also extracted from soil samples collected at organic and conventional farms and was analyzed using both Bradford and enzyme-linked immunosorbent assays. The glomalin content in soils from organic farms was significantly higher than in soils from conventional farms. These results indicate that agricultural practices significantly affect AMF abundance and community structure.

• Mass Spectrometry Letters
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• 제9권1호
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• pp.37-40
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• 2018

Farinomalein is a maleimide-bearing compound well known for its anti-fungal activity. In the present study, synthesis of farinomalein is achieved via Stobbe condensation followed by Haval-Argade contrathermodynamic rearrangement. Kinetically driven Stobbe condensation followed by condensation with beta-alanine reveals formation of two isomers of farinomalein. This article describes application of LC-MS/MS in structure elucidation of farinomalein 1 and its isomers 2 and 3 encountered in its synthesis. The proposed distinct fragmentation pathway is supported by rational organic reaction mechanism. These fragmentation pathways are significant for analytical method development of farinomalein in near future. The structures of farinomalein 1 and its isomers 2 and 3 have been assigned undisputedly.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2005년도 BIOINFO 2005
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• pp.139-143
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• 2005

Cytochrome P450 14${\alpha}$-sterol demethylase enzyme (CYP51) is the target a of azole type antifungals. The azole blocks the ergosterol synthesis and thereby inhibits fungal growth. A three-dimensional (3D) homology model of CYP51 from Candida albicans was constructed based on the X-ray crystal structure of CYP51 from Mycobacterium tuberculosis. Using this model, the binding modes for the substrate (24-methylene-24, 25-dihydrolanosterol) and the known inhibitors (fluconazole, voriconazole, oxiconazole, miconazole) were predicted from docking. Virtual screening was performed employing Structure Based Focusing (SBF). In this procedure, the pharmacophore models for database search were generated from the protein-ligands interactions each other. The initial structure-based virtual screening selected 15 compounds from a commercial available 3D database of approximately 50,000 molecule library, Being evaluated by a cell-based assay, 5 compounds were further identified as the potent inhibitors of Candida albicans CYP51 (CACYP51) with low minimal inhibitory concentration (MIC) range. BMD-09-01${\sim}$BMD-09-04 MIC range was 0.5 ${\mu}$g/ml and BMD-09-05 was 1 ${\mu}$g/ml. These new inhibitors provide a basis for some non-azole antifungal rational design of new, and more efficacious antifungal agents.

• BMB Reports
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• 제46권5호
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• pp.282-287
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• 2013

Cecropin A and papiliocin are novel 37-residue cecropin-like antimicrobial peptides isolated from insect. We have confirmed that papiliocin possess high bacterial cell selectivity and has an ${\alpha}$-helical structure from $Lys^3$ to $Lys^{21}$ and from $Ala^{25}$ to $Val^{35}$, linked by a hinge region. In this study, we demonstrated that both peptides showed high antimicrobial activities against multi-drug resistant Gram negative bacteria as well as fungi. Interactions between these cecropin-like peptides and phospholipid membrane were studied using CD, dye leakage experiments, and NMR experiments, showing that both peptides have strong permeabilizing activities against bacterial cell membranes and fungal membranes as well as $Trp^2$ and $Phe^5$ at the N-terminal helix play an important role in attracting cecropin-like peptides to the negatively charged bacterial cell membrane. Cecropin-like peptides can be potent peptide antibiotics against multi-drug resistant Gram negative bacteria and fungi.

• 한국균학회지
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• 제42권1호
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• pp.34-39
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• 2014

완도의 동백나무 자생지역에서 동백나무의 근권과 주변 일반 식물의 근권 토양을 수집하여 토양 내 수지상균근균(AMF)의 다양성 및 군집 구조를 확인하였다. 분석 결과 두 근권은 모두 Acaulospora mellea 포자로 우점되어 있지만 동백나무 근권에 비해 일반 기주식물의 근권에서 AMF종 다양성 지수와 종 수 및 포자 수가 더 높게 나타나는 경향을 확인하였다. 기주식물의 종류에 상관없이 A. mellea가 높은 빈도로 출현하는 것으로 보아 A. mellea가 다른 AMF종에 비해 산림 토양 및 목본 식물에 특이적으로 적응된 것으로 생각된다. 두 근권에서 발견된 AMF 군집간의 유사도를 분석한 결과 동백나무의 근권에서 발견된 AMF 군집간의 유사도가 동백나무 근권 AMF 군집 일반 기주식물 근권 AMF 군집 간의 유사도나 일반 기주식물 근권 AMF 군집간의 유사도에 비해 더 높은 것으로 나타났다. 이는 동백나무 근권이 다른 일반 기주식물의 근권과는 다른 독특한 AMF 군집 구조를 형성하고 있으며, 식물의 근권 주변의 AMF 군집은 기주식물에 의해 유의미한 수준으로 달라질 수 있음을 보여준다.

• 한국자기공명학회논문지
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• 제13권1호
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• pp.27-34
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• 2009

HP (2-20), a 19-residue peptide derived from the N-terminus of Helicobacter pylori Ribosomal Protein L1, has antimicrobial activity but is not cytotoxic to human erythrocytes. Previously, we have synthesized several analogue peptides to investigate the effects of substitutions on the structure and antimicrobial activity. Substitution of $Gln^{16}$ and $Asp^{18}$ with Trp (Anal 3) caused a dramatic increase in bacterial and fungal lytic activities. In this study, analogue peptides were synthesized to investigate the effects of substitution of Gin and Asp with Phe (Anal 6) or Tyr (Anal 7) in HP (2-20) on its structure and antimicrobial activity. Substitution of Gin and Asp with hydrophobic aromatic residues at position 16 and 18 of HP (2-20) caused increase in antibiotic activity without hemolytic effect. Substitution of Gin and Asp with Trp and Try increased antibiotic activity of HP (220) twice more compared to substitution with Phe. The tertiary structures of Anal 6 and Anal 7 in SDS micelles has been investigated using NMR spectroscopy. The structures revealed that substitutions of the aromatic residues at C-terminus resulted in longer and well defined alpha-helix and improved their antibacterial activities

• The Plant Pathology Journal
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• 제32권2호
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• pp.136-144
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• 2016

Pseudomonas fluorescens pc78 is an effective biocontrol agent for soil-borne fungal diseases. We previously constructed a P43-gfp tagged biocontrol bacteria P. fluorescens pc78-48 to investigate bacterial traits in natural ecosystem and the environmental risk of genetically modified biocontrol bacteria in tomato rhizosphere. Fluctuation of culturable bacteria profile, microbial community structure, and potential horizontal gene transfer was investigated over time after the bacteria treatment to the tomato rhizosphere. Tagged gene transfer to other organisms such as tomato plants and bacteria cultured on various media was examined by polymerase chain reaction, using gene specific primers. Transfer of chromosomally integrated P43-gfp from pc78 to other organisms was not apparent. Population and colony types of culturable bacteria were not significantly affected by the introduction of P. fluorescens pc78 or pc78-48 into tomato rhizosphere. Additionally, terminal restriction fragment length polymorphism profiles were investigated to estimate the influence on the microbial community structure in tomato rhizosphere between non-treated and pc78-48-treated samples. Interestingly, rhizosphere soil treated with strain pc78-48 exhibited a significantly different bacterial community structure compared to that of non-treated rhizosphere soil. Our results suggest that biocontrol bacteria treatment influences microbial community in tomato rhizosphere, while the chromosomally modified biocontrol bacteria may not pose any specific environmental risk in terms of gene transfer.