• The Korean Journal of Mycology
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• v.42 no.4
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• pp.282-288
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• 2014

In this study, we attempted to isolate fungi from soybean fermented foods produced in Sunchang County and to identify Aspergillus oryzae from fungal isolates. Ten fungal isolates were identified with ${\beta}$-tubulin gene. According to the sequences of ${\beta}$-tubulin gene, ten fungal isolates were identified as A. oryzae/flavus complex. For further identification of the ten of fungal isolates, omtA gene, one gene of the aflatoxin biosynthesis gene cluster, was sequenced and the sequences were compared with those of A. oryzae and A. flavus strains from the GenBank database. In addition, identification of the ten fungal isolates was further confirmed using the PCR amplicon of norB and cypA intergenic region, in which a deletion was recognized relative to A. flavus and A. parasiticus. The amplicon size of the ten fungal isolate strains was smaller than those of A. flavus and A. parasiticus, but the same as that of the reference A. oryzae strain. These results indicated that the ten isolates should be identified as A. oryzae. The protease activity in rice koji made with 6, 13, 17, 27, 37 and 38 of strain, respectively was twice higher than that in control. The kojis made with nine of the A. oryzae isolates, respectively, did not produce aflatoxin, suggesting that the strains could possibly be used as starters for soybean products.

• 한국균학회소식:학술대회논문집
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• 2015.05a
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• pp.14-14
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• 2015

Fungi are of particular interest due to their capacity to produce an extensive array of secondary metabolites. While many secondary metabolites have no known functions to the producing fungal organisms, these metabolites have tremendous importance to humans with beneficial (e.g., antibiotics) or detrimental (e.g., mycotoxins) properties. In this study, two important filamentous fungi, Fusarium verticillioides and Mycosphaerella graminicola were selected as target species and the genes regulatory functions on the biosynthesis of secondary metabolisms were studied. Functional genomics including forward and reverse genetics, and proteomics were utilized to better understand the complex secondary metabolism regulations in both F. verticillioides and M. graminicola. Identified genes in either F. verticillioides or M. graminicola background were CPP1 (a putative protein phosphatase gene), GAC1 (encoding a GTPase activating protein), MCC1(encoding c-type cyclin), and the velvet gene, MVE1. Our data suggest that there are diverse regulatory genes on fungal secondary metabolites with distinct or overlapping functional roles.

• Korean Journal of Microbiology
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• v.35 no.1
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• pp.25-27
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• 1999

Degenerate primers corresponding to the sequences of the copper-binding regions in the fungal laccases were used to isolatc laccase gene specific fragment by PCR in Coprinus congregahts. A 144 bp DNA hagrnent was cloned and was identified to have 60-69 % homology with other fungal laccase genes. The predicted amino acid sequcnces showed 68-75% homology with other fungal laccase proteins.

• Mycobiology
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• v.49 no.3
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• pp.258-266
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• 2021

The velvet regulators VosA and VelB are primarily involved in spore maturation and dormancy. Previous studies found that the VosA-VelB hetero-complex coordinates certain target genes that are related to fungal differentiation and conidial maturation in Aspergillus nidulans. Here, we characterized the VosA/VelB-inhibited developmental gene vidD in A. nidulans. Phenotypic analyses demonstrated that the vidD deleted mutant exhibited defect fungal growth, a reduced number of conidia, and delayed formation of sexual fruiting bodies. The deletion of vidD decreased the amount of conidial trehalose, increased the sensitivity against heat stress, and reduced the conidial viability. Moreover, the absence of vidD resulted in increased production of sterigmatocystin. Together, these results show that VidD is required for proper fungal growth, development, and sterigmatocystin production in A. nidulans.

• The Korean Journal of Mycology
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• v.45 no.4
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• pp.292-303
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• 2017

During a survey of culturable fungi in Korea, 18 unrecorded fungal species were isolated and identified from the indoor air of mushroom cultivation houses, the materials used for preparation of mushroom cultivation media, wild plants, and funitures. This study reports the descriptions of the 18 unrecorded fungal species: Aspergillus creber, Ceratocystis paradoxa, Colletotrichum spaethianum, Coniochaeta velutina, Coprinellus xanthothrix, Epicoccum sorghinum, Leptosphaeria rubefaciens, Myrothecium gramineum, Paraconiothyrium fuckelii, Penicillium erubescens, Penicillium melinii, Penicillium pulvillorum, Penicillium sabulosum, Penicillium turbatum, Pestalotiopsis portugalica, Pilidiella castaneicola, Rachicladosporium pini, and Umbelopsis nana. For all the identified species, the morphological characteristics including the features of colony formed on media, images of light microscopy, and molecular phylogenetic relationships based on nucleotide sequences of the internal transcribed spacer ribosomal DNA (ITS rDNA), 18S rDNA, 28S rDNA, ${\beta}-tubulin$ gene, calmodulin gene, and translation elongation factor gene were described.

• The Plant Pathology Journal
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• v.28 no.4
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• pp.364-372
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• 2012

Xanthomonas oryzae pv. oryzae causing bacterial leaf blight disease in rice produces and secretes Hpa1 protein that belongs to harpin protein family. Previously it was reported that Hpa1 induced defense responses when it was produced in tobacco. In this study, we expressed hpa1 gene in rice and Arabidopsis to examine the effects of Hpa1 expression on disease resistance to both fungal and bacterial pathogens. Expression of hpa1 gene in rice enhanced disease resistance to both X. oryzae pv. oryzae and Magnaporthe grisea. Interestingly, individual transgenic rice plants could be divided into four groups, depending on responses to both pathogens. hpa1 expression in Arabidopsis also enhanced disease resistance to both Botrytis cineria and Xanthomonas campestris pv. campestris. To examine genes that are up-regulated in the transgenic rice plants after inoculation with X. oryzae pv. oryzae, known defense-related genes were assessed, and also microarray analysis with the Rice 5 K DNA chip was performed. Interestingly, expression of OsACS1 gene, which was found as the gene that showed the highest induction, was induced earlier and stronger than that in the wild type plant. These results indicate that hpa1 expression in the diverse plant species, including monocot and dicot, can enhance disease resistance to both fungal and bacterial plant pathogens.

• The Plant Pathology Journal
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• v.37 no.3
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• pp.268-279
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• 2021

Citrus scab, caused by the fungal pathogen Elsinoë fawcettii, is one of the most important fungal diseases affecting Citrus spp. Citrus scab affects young tissues, including the leaves, twigs, and fruits, and produces severe fruit blemishes that reduce the market value of fresh fruits. To study the molecular responses of satsuma mandarin (C. unshiu) to E. fawcettii, plant hormone-related gene expression was analyzed in response to host-compatible (SM16-1) and host-incompatible (DAR70024) isolates. In the early phase of infection by E. fawcettii, jasmonic acid- and salicylic acid-related gene expression was induced in response to infection with the compatible isolate. However, as symptoms advanced during the late phase of the infection, the jasmonic acid- and salicylic acid-related gene expression was downregulated. The gene expression patterns were compared between compatible and incompatible interactions. As scabs were accompanied by altered tissue growth surrounding the infection site, we conducted gibberellic acid- and abscisic acid-related gene expression analysis and assessed the content of these acids during scab symptom development. Our results showed that gibberellic and abscisic acid-related gene expression and hormonal changes were reduced and induced in response to the infection, respectively. Accordingly, we propose that jasmonic and salicylic acids play a role in the early response to citrus scab, whereas gibberellic and abscisic acids participate in symptom development.

• The Plant Pathology Journal
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• v.17 no.6
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• pp.376.1-376
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• 2001

• The Plant Pathology Journal
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• v.25 no.3
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• pp.205-212
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• 2009

Colletotrichum acutatum was the main cause of the recent outbreaks of anthracnose on pepper fruit in Korea. To facilitate molecular analysis of C. acutatum, we generated an arginine auxotrophic mutant of the C acutatum strain JC24 using a targeted gene replacement strategy. A 3.3-kb genomic region carrying an ortholog (designated CaARG2) of the fungal gene encoding N-acetylglutamate synthase, the first enzyme of arginine biosynthesis in fungi, was deleted from the fungal genome. The mutant exhibited normal growth only when arginine was exogenously supplied into the culture medium. Transformation of the arginine auxotrophic mutant with a plasmid DNA carrying an intact copy of CaARG2, which was smaller than the deleted region in the mutant, not only caused random vector insertions in the fungal genome, but also recovered both hyphal growth and pathogenicity of the mutant to the wild-type level. Using this new selection system, we have successfully developed a restriction enzyme-mediated integration procedure, which would provide an economically efficient random mutagenesis method in C. acutatum.

• Journal of Plant Biotechnology
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• v.6 no.3
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• pp.151-156
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• 2004

Soil-borne fungal pathogens such as Verticillium and Rhizoctonia can colonize in the stem tissue of plant through root and lead to wilting symptoms of plant by blocking. water transportation. During the colonization of Rhizoctonia solani in the vascular tissue of tomato stems, particularly, phenylalanine ammonia-lyase (PAL) gene induction pattern was cyclized showing peak induction at two different time points (10 and 80 h) after fungal spores inoculation in vivo. In leaves or roots, however, no such cycling pattern was observed. The first induction peak may be due to an initial sporulation events leading to a second induction peak by a proliferation of fungal spores to the upper stems or other tissues from an initial spore trapping sites. Tomato PAL gene was also dramatically induced by wounding, light illumination and mercury chloride treatment but was not cyclized. Mercury chloride showed the earliest induction with all tissues even at half an hour after treatment.