• Research in Plant Disease
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• v.13 no.3
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• pp.204-206
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• 2007

In 2006 to 2007, the potential inoculum source of the anthracnose of sweet persimmon caused by Colletotrichum gloeosporioides was surveyed. The infected twigs, buds, dead twigs, petiole, leaves, dropped fruits were collected and tested for their possibility as overwintering inoculum. The detection rates of the pathogen from various parts of sweet persimmon tree were varied. When the collected samples were examined in April. Over than 93.3% of infected twig samples were harbored mycelia of C. gloeosporioides, and 46.7% of infected buds, 36.7% of dead twigs, 23.3% of petioles, and 16.7% of leaves were beared pathogenic fungus. No pathogenic fungus were detecded from healthy twigs and buds. Infected twigs and bud was important overwintering sites and formed conidia actively in next spring. The infected twigs, leaves, petioles, and fruits in growing season produced great number of conidia and caused active dissemination of the anthracnose disease in sweet persimmon. In growing season, all of the infected parts, such as twigs, leaves, petioles, and fruits produced pathogenic fungus.

• Journal of Microbiology and Biotechnology
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• v.22 no.7
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• pp.889-893
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• 2012

Appressorium is a specialized infection structure of filamentous pathogenic fungi and plays an important role in establishing a pathogenic relationship with the host. The Egh16/Egh16H family members are involved in appressorium formation and pathogenesis in pathogenic filamentous fungi. In this study, a homolog of Egh16H, Magas1, was identified from an entomopathogenic fungus, Metarhizium acridum. The Magas1 protein shared a number of conserved motifs with other Egh16/Egh16H family members and specifically expressed during the appressorium development period. Magas1-EGFP fusion expression showed that Magas1 protein was not localized inside the cell. Deletion of the Magas1 gene had no impact on vegetative growth, conidiation and appressorium formation, but resulted in a decreased mortality of host insect when topically inoculated. However, the mortality was not significant between the Magas1 deletion mutant and wild-type treatment when the cuticle was bypassed by injecting conidia directly into the hemocoel. Our results suggested that Magas1 may influence virulence by affecting the penetration of the insects' cuticle.

• The Plant Pathology Journal
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• v.21 no.3
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• pp.297-300
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• 2005

Racodium therryanum from Korea is described here for the first time. This fungus is characterized by that it is isolated from conifer seeds and seedlings, including Abies, colonies are dark green to dark gray and intricate, and it forms chlamydospores in cultures. This pathogenic fungus was isolated from seeds of Abies koreana growing on Mt. Halla, Jeju island. The fungus stopped growth more than at $30^{\circ}C$ but grew even at $O^{\circ}C$. This fungus infected seeds of A. koreana under the snow during winter season. There is a high probability that this fungus affects the natural regeneration of A. koreana on Mt. Halla.

• The Plant Pathology Journal
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• v.26 no.3
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• pp.289-292
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• 2010

This study used a modified cetyltrimethylammonium bromide (CTAB) method to efficiently extract DNA from the plant pathogenic fungus Cercospora sojina. Total DNA yield obtained by this method was approximately 1 mg/g of mycelia (fresh weight), and the mean ratio of A260/A280 and A260/A230 were 2.04 and 2.1, respectively. The results of random amplified polymorphic DNA (RAPD) analysis, digestion with restriction enzymes, and Southern hybridization indicated that polysaccharides were effectively removed by this method, and the resulting DNA was sufficient for use in subsequent molecular analysis.

• The Plant Pathology Journal
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• v.19 no.5
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• pp.266-268
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• 2003

In 2002, sooty mold was observed on persimmon (Diopyros kald) from the Jinju Agricultural Products Wholesale Market in Gyeongnam, Korea. The lesion of the sooty mold usually appeared as scars or wounds formed on the surface of the fruits. The symptom started with water soaking lesion, then the fruit softened rapidly. Colony of the causal pathogenic fungus was dark green in color on potato dextrose agar. The diameter of growing hyphae was 1-2 $\mu\textrm{m}$. The mostly one-celled conidia were ovoid, lemon or cylinder in shape, blastophores, and sized 46-132 $\mu\textrm{m}$. Erected conidiophores were long-branched chains and their lengths varied from 24 to 346 $\mu\textrm{m}$ with 2-5 $\mu\textrm{m}$ width. The optimum temperature for mycelial growth was about 2$0^{\circ}C$. Based on their mycological characteristics, the fungus was identified as Cladosporium cladosporioides. This is the first report in Korea of the sooty mold of persimmon caused by the said fungus.

• Mycobiology
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• v.48 no.5
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• pp.418-422
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• 2020

In 2016, a cercosporoid fungus was found from leaf spot symptoms on melon in Korea. The fungus isolated from the plant was identified based on morphological characteristics and sequence analyses of five genes (ITS rDNA, translation elongation factor 1-α, actin, calmodulin, and histone H3). The fungal isolate was found to be pathogenic to melon. The results confirm that the fungus associated with leaf spot on melon was Cercospora cf. flagellaris. This is the first report of Cercospora cf. flagellaris causing Cercospora leaf spot on melon in Korea.

• Mycobiology
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• v.49 no.5
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• pp.498-506
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• 2021

An endophytic fungus strain DYSJ3 was isolated from a stem of Aphanamixis grandifolia Blume, which was identified as Aspergillus versicolor based on the morphological characteristics, internal transcribed spacer (ITS) and calmodulin gene sequences analyses. A. versicolor DYSJ3 exhibited strong antagonistic activity against Colletotrichum musae, C. gloeosporioides and Fusarium oxysporum f. sp. cubense with the inhibition rates of 61.9, 51.2 and 55.3% respectively. The antifungal metabolites mainly existed in the mycelium of A. versicolor DYSJ3, and its mycelial crude extract (CE) had broad-spectrum antifungal activities against plant pathogenic fungi. The CE had a good thermal stability, and the inhibition rate of 100 mg/mL CE against C. musae was above 70.0% after disposing at 120 ℃ for 1 h. Five secondary metabolites were isolated from the CE and identified as averufanin, ergosterol peroxide, versicolorin B, averythrin and sterigmatocystin. Activity evaluation showed versicolorin B exhibited inhibitory effects on the mycelial growth and conidial germination of C. musae, and sterigmatocystin had a weak inhibitory effect on the mycelial growth of C. musae.

• 한국전자현미경학회:학술대회논문집
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• 2003.05a
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• pp.39-39
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• 2003

• Mycobiology
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• v.43 no.3
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• pp.179-183
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• 2015

Zinc is an essential micronutrient required for many enzymes that play essential roles in a cell. It was estimated that approximately 3% of the total cellular proteins are required for zinc for their functions. Zinc has long been considered as one of the key players in host-pathogen interactions. The host sequesters intracellular zinc by utilizing multiple cellular zinc importers and exporters as a means of nutritional immunity. To overcome extreme zinc limitation within the host environment, pathogenic microbes have successfully evolved a number of mechanisms to secure sufficient concentrations of zinc for their survival and pathogenesis. In this review, we briefly discuss the zinc uptake systems and their regulation in the model fungus Saccharomyces cerevisiae and in major human pathogenic fungi such as Aspergillus fumigatus, Candida albicans, and Cryptococcus gattii.

• Journal of Microbiology and Biotechnology
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• v.34 no.8
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• pp.1551-1562
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• 2024

Fungi employ diverse mechanisms for iron uptake to ensure proliferation and survival in iron-limited environments. Siderophores are secondary metabolite small molecules with a high affinity specifically for ferric iron; these molecules play an essential role in iron acquisition in fungi and significantly influence fungal physiology and virulence. Fungal siderophores, which are primarily hydroxamate types, are synthesized via non-ribosomal peptide synthetases (NRPS) or NRPS-independent pathways. Following synthesis, siderophores are excreted, chelate iron, and are transported into the cell by specific cell membrane transporters. In several human pathogenic fungi, siderophores are pivotal for virulence, as inhibition of their synthesis or transport significantly reduces disease in murine models of infection. This review briefly highlights siderophore biosynthesis and transport mechanisms in fungal pathogens as well the model fungi Saccharomyces cerevisiae and Schizosaccharomyces pombe. Understanding siderophore biosynthesis and transport in pathogenic fungi provides valuable insights into fungal biology and illuminates potential therapeutic targets for combating fungal infections.