• Mycobiology
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• 제30권3호
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• pp.117-127
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• 2002

Cleistothecial development in Aspergillus nidulans(teleomorph, Emericella nidulans) was examined with the transmission electron microscopy. Cleistothecial initial was a small coiled lump of cells, ca. 6 ${\mu}m$ in diameter, which was consisted of a slightly swollen core with a short "tail" hypha. Initials were wrapped with a loose layer of hyphae. Core cells of cleistothecial initials were broad and multinucleated at first, then formed dikaryotic ascogenous cells, followed by post-meiotic tetra-nucleate or octa-nucleate protoasci and finally mature ascospores. Croziers were formed early during cleistothecium development. The peridial layer of mature cleistothecia was derived from the wrapping hyphae which originally invested the young cleistothecium. Completion of peridial layers development was associated with the depositing of a non-enzyme reactive material around peridial cells. $H\ddot{u}lle$ cell formation during the cleistothecial development appeared to be somewhat coordinated with the developmental stages of cleistothecium.

• Mycobiology
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• 제43권1호
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• pp.31-36
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• 2015

We have previously isolated ${\varepsilon}$-COP, the ${\alpha}$-COP interactor in COPI of Aspergillus nidulans, by yeast two-hybrid screening. To understand the function of ${\varepsilon}$-COP, the $aneA^+$ gene for ${\varepsilon}$-COP/AneA was deleted by homologous recombination using a gene-specific disruption cassette. Deletion of the ${\varepsilon}$-COP gene showed no detectable changes in vegetative growth or asexual development, but resulted in decrease in the production of the fruiting body, cleistothecium, under conditions favorable for sexual development. Unlike in the budding yeast Saccharomyces cerevisiae, in A. nidulans, over-expression of ${\varepsilon}$-COP did not rescue the thermo-sensitive growth defect of the ${\alpha}$-COP mutant at $42^{\circ}C$. Together, these data show that ${\varepsilon}$-COP is not essential for viability, but it plays a role in fruiting body formation in A. nidulans.

• Journal of Microbiology and Biotechnology
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• 제3권2호
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• pp.134-138
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• 1993

Monascus anka 732Y3 was induced from Monascus anka KFCC 11832 (IFO 4478, ATCC 16360) by ultra-violet light irradiation. The growth of this new fungus is frequently more dependent on sexual propagation than asexual propagation, compared with that of its parental strain, M. anka KFCC 11832. Less conidia than those of M. anka KFCC 11832 were observed by a microscope. The optical density of the red pigments ($OD_{500}$) produced by M. anka 732Y3 was 157, which was about 10 times higer than that of M. anka KFCC 11832. Such high production of the red pigments by the mutant could be explained by the following observations.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 추계 학술논문 발표대회
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• pp.95-96
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• 2012

This study makes with the environment-friendly artificial stone which doesn't use the cement and natural aggregate and increases the blast furnace slag that is the eco-friendly material that is the industrial byproduct, fly ash, and availability of the red mud and applies the coares aggregate substitute material as the cleistothecium. The experimental plan according to it indicated the compressive strength and flexural strength which is the most excellent in the mixied ratio 40% of the result degree of closeness magnetism of experimenting with the optimal mix obtained through the preceding stude.

• 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.

• Journal of Microbiology
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• 제41권1호
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• pp.34-40
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• 2003

Aspergillus nidulans, a homothalic ascomycete, has a complete sexual reproductive cycle as well as an asexual one. Both sexual and asexual development are known to be genetically programmed, but are also strongly affected by environmental factors including nutrients, light, temperature and osmolarity. We have examined these factors to define favored conditions for fruiting body (cleistothecium) formation. In general, fruiting body formation was enhanced where carbon and nitrogen sources were sufficient. Limitation of C-source caused predominant asexual development while inhibiting sexual development. When higher concentrations of glucose were supplied, more cleistothecia were formed. Other carbon sources including lactose, galactose and glycerol made the fungus develop cleistothecia very well, whereas acetate caused asexual sporulation only. Organic nitrogen sources like casein hydrolysate and glycine, and an increase in nitrate or ammonium concentration also enhanced sexual development. In addition to nutrient effects, low levels of aerobic respiration, caused either by platesealing or treatment with various chemicals, favored sexual development. Carbon limitation, light exposure and a high concentration of salts promoted asexual development preferentially, suggesting that stress conditions may drive the cell to develop asexual sporulation while comfortable and wellnourished growth conditions favored sexual development.

• 식물병연구
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• 제8권3호
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• pp.166-170
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• 2002

2000년 가을에 경기도 수원의 녹두재배포장에서 흰가루병이 발생하여 병원균의 형태 등을 조사하였다. 병징은잎의 앞면, 뒷면과 잎자루에서 흰가루의 균총이 형성되어서 진전됨에 따라서 잎이 황화되어 말라서 결국 낙엽이 되었다. 이 병원균의 분생포자는 분생자경의 끝에 연쇄적으로 생기며, 무색, 단세포, 타원형내지 장타원형으로 피브로신체를 가지고 있으며, 그 크기는 25~38$\times$16~22 $\mu\textrm{m}$ 이었다. 분생포자의 발아관은 단순발아관이며, 부착기는 뚜렷하지 않았고, 분생자경은 거의 수직으로 분지하였고, 기부는 대부분 직선상이었으며, 그 길이는 67~100 $\mu\textrm{m}$ 이었다. 기부세포는 길이가 37~65 $\mu\textrm{m}$, 폭이 10~11 $\mu\textrm{m}$ 이었다. 그리고 부착기는 뚜렷하지 않았으며, 발아관은 단순형이며 분지하지 않았다. 폐쇄자낭각은 구형이나 편구형으로 크기가 85~1130 $\mu\textrm{m}$이며, 부속사는 6-11개이며, 격막이 1~7개, 크기가 192~223$\times$5~7 $\mu\textrm{m}$ 이었다 벽세포는 불규칙다각형으로 15~45$\times$7~26 $\mu\textrm{m}$의 크기이며, 폐쇄자낭각은 하나의 자낭을 가지고 있으며, 자낭은 계란형 또는 반구형으로 8개의 자낭포자를 가지고 있으며, 크기는 62~95$\times$50~67 $\mu\textrm{m}$이었다. 자낭포자는 난원형 또는 반구형으로 크기가 16~24$\times$12~16 $\mu\textrm{m}$ 이었다. 이상의 결과로 Sphae개theca phaseoli 의한 녹두흰가루병으로 동정되어 국내에서 처음으로 보고한다.