• Mycobiology
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• 제50권1호
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• pp.12-19
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• 2022

Paramyrothecium eichhorniae sp. nov. was observed and collected from Chiang Mai and Phetchaburi Provinces, Thailand. This new species is introduced based on morphological and molecular evidence. This fungus is characterized by its production of sporodochium conidiomata with a white setose fringe surrounding an olivaceous green to dark green slimy mass of conidia, penicillately branched conidiophores, and aseptate and cylindrical to ellipsoid conidia. Phylogenetic analyses of combined LSU rDNA, ITS rDNA, tef1, rpb2, tub2 and cmdA sequence data using maximum parsimony, maximum likelihood and Bayesian approaches placed the fungus in a strongly supported clade with other Paramyrothecium species in Stachybotryaceae (Hypocreales, Sordariomycetes). The descriptions of the species are accompanied by illustrations of morphological features, and a discussion of the related taxa is presented.

• Mycobiology
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• 제50권6호
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• pp.467-474
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• 2022

Autophagy serves as a survival mechanism and plays important role in nutrient recycling under conditions of starvation, nutrient storage, ad differentiation of plant pathogenic fungi. However, autophagy-related genes have not been investigated in Colletotrichum scovillei, a causal agent of pepper fruit anthracnose disease. ATG8 is involved in autophagosome formation and is considered a marker of autophagy. Therefore, we generated an ATG8 deletion mutant, ΔCsatg8, via homologous recombination to determine the functional roles of CsATG8 in the development and virulence of C. scovillei. Compared with the wild-type, the deletion mutant ΔCsatg8 exhibited a severe reduction in conidiation. Conidia produced by ΔCsatg8 were defective in survival, conidial germination, and appressorium formation. Moreover, conidia of ΔCsatg8 showed reduced lipid amount and PTS1 selectivity. A virulence assay showed that anthracnose development on pepper fruits was reduced in ΔCsatg8. Taken together, our results suggest that CsATG8 plays various roles in conidium production and associated development, and virulence in C. scovillei.

• 생물환경조절학회지
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• 제29권1호
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• pp.96-102
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• 2020

Fusarim oxysporum에 의한 덩굴쪼김병은 수박 재배에 큰 피해를 일으키는 중요한 병이다. 이 병을 방제하기 위해 덩굴 쪼김병 저항성 박 대목을 이용하는 것이 가장 좋은 방법이다. 본 연구는 박 덩굴쪼김병 저항성 자원을 선발할 수 있는 방법을 확립하기 위해 수행하였다. 효과적인 접종법을 개발하기 위해 접종 후 온도(15, 20, 25, 30℃), 접종 농도(1 × 10⁵, 5 × 10⁵, 1 × 10⁶, and 5 × 10⁶ conidia·mL^-1), 접종 시기(파종 7, 10, 13, 16일 후)를 조사하였다. 박 덩굴쪼김병을 접종하였을 때 접종 후 배양 온도나 파종 후 접종 시기의 영향이 적었다. 그러나, 덩굴쪼김병에 저항성인 박의 경우 접종농도가 높을수록 발병이 심하게 나타났다. 따라서, 박 덩굴쪼김병에 대한 효과적인 접종법으로 파종 10일 된 유묘 뿌리를 1 × 10⁵ - 1 × 10⁶ conidia·mL^-1 농도로 30분간 접종한 후 감염되지 않은 토양에 옮겨 심고 25℃에서 3주 동안 재배하는 것을 제안한다.

• The Plant Pathology Journal
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• 제33권3호
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• pp.337-344
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• 2017

To develop a commercial product using the mycoparasitic fungus Simplicillium lamellicola BCP, the scale-up of conidia production from a 5-l jar to a 5,000-l pilot bioreactor, optimization of the freeze-drying of the fermentation broth, and preparation of a wettable powder-type formulation were performed. Then, its disease control efficacy was evaluated against gray mold diseases of tomato and ginseng plants in field conditions. The final conidial yields of S. lamellicola BCP were $3.3{\times}10^9conidia/ml$ for a 5-l jar, $3.5{\times}10^9conidia/ml$ for a 500-l pilot vessel, and $3.1{\times}10^9conidia/ml$ for a 5,000-l pilot bioreactor. The conidial yield in the 5,000-l pilot bioreactor was comparable to that in the 5-l jar and 500-l pilot vessel. On the other hand, the highest conidial viability of 86% was obtained by the freeze-drying method using an additive combination of lactose, trehalose, soybean meal, and glycerin. Using the freeze-dried sample, a wettable powder-type formulation (active ingredient 10%; BCP-WP10) was prepared. A conidial viability of more than 50% was maintained in BCP-WP10 until 22 weeks for storage at $40^{\circ}C$. BCP-WP10 effectively suppressed the development of gray mold disease on tomato with control efficacies of 64.7% and 82.6% at 500- and 250-fold dilutions, respectively. It also reduced the incidence of gray mold on ginseng by 65.6% and 81.3% at 500- and 250-fold dilutions, respectively. The results indicated that the new microbial fungicide BCP-WP10 can be used widely to control gray mold diseases of various crops including tomato and ginseng.

• 한국응용곤충학회지
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• 제1권
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• pp.26-28
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• 1962

도열병균의 분생포자를 다량으로 형성하는 배지를 찾고자 여러 가지 영양분을 차진 한천 및 액체배지에 대하여 분생포자형성도를 시험하였다. 여러 가지 공시 배지 중에서 V-8배양액과 토마토 즙한천배지 상에서 가장 많은 분생포자가 형성되었고, 볏짚배지 상에서 가장 적은 수의 분생포자카 형성되였다. 이와 같이 V-8즙배양액화 토마토한천배지는 도열병균 분생포자형성도에 있어서 과거 연구자들이 최적이라고 보고한 쌀겨한천배지와 효모전분한천배지를 훨씬 능가하였다.

• Mycobiology
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• 제47권4호
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• pp.457-465
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• 2019

MonA is a subunit of a guanine nucleotide exchange factor that is important for vacuole passing and autophagy processes in eukaryotes. In this study, we characterized the function of MonA, an orthologue of Saccharomyces cerevisiae Mon1, in the model fungus Aspergillus nidulans and a toxigenic fungus A. flavus. In A. nidulans, the absence of AnimonA led to decreased fungal growth, reduced asexual reproduction, and defective cleistothecia production. In addition, AnimonA deletion mutants exhibited decreased spore viability, had reduced trehalose contents in conidia, and were sensitive to thermal stress. In A. flavus, deletion of AflmonA caused decreased fungal growth and defective production of asexual spores and sclerotia structures. Moreover, the absence of monA affected vacuole morphology in both species. Taken together, these results indicate that MonA plays conserved roles in controlling fungal growth, development and vacuole morphology in A. nidulans and A. flavus.

• Mycobiology
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• 제49권3호
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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.

• 한국식품위생안전성학회지
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• 제6권3호
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• pp.119-126
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• 1991

Penicillium citrinum의 생육과 citrinin 생성에 젖산균이 미치는 영향을 조사하기 위하여 Penicillium citrinum을 치이즈 열성균인 Lactobacillus casei 및 Lactobacillus Bulgaricus와 혼합배의를 실시하였다. 즉 glucose를 7% 첨가한 APT 배지에 공식균을 각각 독립배의한 경우(Pc, Lb 및 Lc) , Penicillium citrinum 과 Lactobacillus spp.를 동시에 접종, 배양한 경우(ST; Pc＋Lb 및 Pc＋Lc) , Lactobacillus spp.를 접종하여 3일간 배양한 후 Penicillium citrinum을 접종하여 배양한 경우(LbPc 및 LcPc), 그리고 Penicillium citrinum을 접종하여 3일간 배양한 후 Lactobacillus spp.를 접종하여 배양한 경우 (PcLb 및 PcLc)로 구분하여 각각 30℃에서 15일간 정식 배의하면서 경시적으로 (0, 3, 6, 9, 12, 15일) 배의 액의 pH와 산도를 측정하고 공식균의 생육과 citrinin 생성을 비교하였다. 그 결과 , 균의 생육은 혼합배의 의 경우 Penicillium citrinum의 성장이 크게 둔화되었고 특히 젖산균을 먼저 접종한 군(PcLb 및 PcLc)의 경우 더욱 현저히 나타났다. Citrinin의 생성은 곰팡이 대조군(Pc)과 곰팡이를 먼저 접종한군(PcLb 및 PcLc) 에서는 비슷한 함량을 보였으나 곰팡이와 세균을 동시 접종한 경우 (ST) 감소되었고, 특히 Lactobacillus spp. 배양 후 Penicillium citrinum을 접종한 군(LbPc 및 LcPc)에서는 citrinin 생성이 나타나지 않아 Penicillium citrinum의 생육과 citrinin 생성이 경쟁적으로 작용하는 microflora에 의해 큰 영향을 받는 것으로 나타났다.

• Journal of Microbiology and Biotechnology
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• 제31권5호
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• pp.676-685
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• 2021

RNA-binding proteins are involved in RNA metabolism and posttranscriptional regulation of various fundamental biological processes. The PUF family of RNA-binding proteins is highly conserved in eukaryotes, and its members regulate gene expression, mitochondrial biogenesis, and RNA processing. However, their biological functions in Aspergillus species remain mostly unknown in filamentous fungi. Here we have characterized the puf genes in the model organism Aspergillus nidulans. We generated deletion mutant strains for the five putative puf genes present in the A. nidulans genome and investigated their developmental phenotypes. Deletion of pufA or pufE affected fungal growth and asexual development. pufA mutants exhibited decreased production of asexual spores and reduced mRNA expression of genes regulating asexual development. The pufE deletion reduced colony growth, increased formation of asexual spores, and delayed production of sexual fruiting bodies. In addition, the absence of pufE reduced both sterigmatocystin production and the mRNA levels of genes in the sterigmatocystin cluster. Finally, pufE deletion mutants showed reduced trehalose production and lower resistance to thermal stress. Overall, these results demonstrate that PufA and PufE play roles in the development and sterigmatocystin metabolism in A. nidulans.

• Journal of Microbiology and Biotechnology
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• 제28권5호
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• pp.748-756
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• 2018

Biofilms are of vital significance in bioconversion and biotechnological processes. In this work, sugarcane molasses was used to enhance biofilms for the improvement of the production of fumigaclavine C (FC), a conidiation-associated ergot alkaloid with strong anti-inflammatory activities. Biofilm formation was more greatly induced by the addition of molasses than the addition of other reported biofilm inducers. With the optimal molasses concentration (400 g/l), the biofilm biomass was 6-fold higher than that with sucrose, and FC and conidia production was increased by 5.8- and 3.1-fold, respectively. Moreover, the global secondary metabolism regulatory gene laeA, FC biosynthetic gene fgaOx3, and asexual central regulatory genes brlA and wetA were upregulated in molasses-based biofilms, suggesting the upregulation of both asexual development and FC biosynthesis. This study provides novel insight into the stimulatory effects of molasses on biofilm formation and supports the widespread application of molasses as an inexpensive raw material and effective inducer for biofilm production.