• 한국균학회지
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• 제43권1호
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• pp.33-39
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• 2015

사상성 진균에서 veA 유전자와 연계되어 있는 velvet 복합체는 진균의 분화와 이차 대사산물의 조절에 매우 중요한 기능을 한다. 모델 사상균인 Aspergillus nidulans의 경우 methyltransferase인 VipB와 VipC를 포함한 여러 단백질들이 VeA 단백질과 상호작용하는 것으로 알려져 있다. 본 연구에서는 인간 기회감염 진균인 Aspergillus fumigatus에서 vipB와 vipC 유전자의 상동유전자를 분리하여 각각 AfuvipB와 AfuvipC로 명명하였다. AfuvipB 유전자는 AspGD 데이터베이스에 Afu3g14920으로 등록되어 있으며 1,510 bp 길이에 10개의 인트론을 가지고 있고, 유전자 산물은 336 아미노산 잔기로 구성된 단백질로 methyltransferase 도메인을 가지고 있었다. AfuvipC는 Afu8g01930으로 AfuvipB와 유사하게 10개의 인트론을 가지고 있으며 339개의 아미노산으로 구성된 methyltransferase를 암호화하고 있었다. A. fumigatus에서 각각의 유전자에 대한 기능을 알아보고자 유전자제거 돌연변이 균주들을 제조하고 그들의 표현형을 관찰하였다. AfuvipB 유전자 제거 돌연변이는 점 접종을 하였을 경우 대조군에 비하여 표현형의 차이를 보이지 않았다. 그러나 단일 포자에서 성장한 콜로니를 비교해 보았을 때 대조군에 비하여 그 크기가 작고 분화 속도도 약간 더딘 것을 관찰할 수 있었다. 반면에 AfuvipC 유전자 제거 돌연변이는 대조군과 비교하였을 때 표현형의 차이를 보이지 않았다. 이러한 결과는 두 개의 methyltransferase가 상호 중복적인 역할을 수행하거나 정상적인 실험실 배양조건에서는 중요한 기능을 수행하지 않을 수 있음을 시사한다.

• Journal of Microbiology and Biotechnology
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• 제8권6호
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• pp.568-574
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• 1998

Two types of chitosanases produced from Aspergillus fumigatus KH-94 were purified by ion exchange and gel permeation chromatography. Molecular weights of the enzymes are 22.5 kDa (chitosanase I) and 108 kDa (chitosanase II). pI, optimum pH, and temperature of chitosanase I are 7.3, 5.5, and 70-$80^{\circ}C$, respectively, and those of chitosanase II are 4.8, 4.5~5.5, and 50~$60^{\circ}C$, respectively. Activities of both chitosanases were increased by $Mn^{2+}$ but inhibited by $Cu^{2+}$ and $Hg^{2+}$ . Chitosanase I has endo-splitting activity that hydrolyzes chitopentaose, chitohexaose, and chitosan to chitobiose, chitotriose, and chitotetraose, whereas chitosanase II has exo-splitting activity that hydrolyzes chitobiose and chitosan to glucosamine. Chitosanase II was found to have transglycosylation activity also in the reaction of 2% more chitooligosaccharides as a substrate and at the initial reaction. The higher degree of deacetylation, the stronger activities of chitosanase Iand II toward chitosans. Both chitosanases could hydrolyze chitosan and glycol chitosan but not chitin, cellulose, and carboxymethyl cellulose. To produce higher degree of polymerization of chitooligosaccharides, chitosanase I was used and yielded 80% of recovery.

• Fisheries and Aquatic Sciences
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• 제19권9호
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• pp.35.1-35.6
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• 2016

Gliotoxin has been recognized as an immunosuppressive agent for a long time. Recently, it was reported to have antitumor properties. However, the mechanisms by which it inhibits tumors remain unclear. Here, we showed that gliotoxin isolated from the marine fungus Aspergillus fumigatus inhibited proliferation and induced apoptosis in HT1080 human fibrosarcoma cells. Gliotoxin repressed phosphorylation-dependent degradation of $I{\kappa}B-{\alpha}$, an antagonist of nuclear factor kappa B ($NF-{\kappa}B$), which is a known tumor-promoting factor. This coincided with a decrease in nuclear import of $NF-{\kappa}B$, suggesting its signaling activity was impaired. Moreover, gliotoxin increased intracellular reactive oxygen species (ROS). Since ROS have been known to inhibit $NF-{\kappa}B$, this may also contribute to gliotoxin's antitumorigenic effects. These results suggest that gliotoxin suppressed the activation of $NF-{\kappa}B$ by inhibiting phosphorylation and degradation of $I{\kappa}B-{\alpha}$ and by increasing ROS, which resulted in apoptosis of HT1080 cells. Cumulatively, gliotoxin is a promising candidate antagonist of $NF-{\kappa}B$, and it should be investigated for its possible use as a selective inhibitor of human fibrosarcoma cells.

• Molecules and Cells
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• 제43권9호
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• pp.831-840
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• 2020

The β-class of carbonic anhydrases (β-CAs) are zinc metalloenzymes widely distributed in the fungal kingdom that play essential roles in growth, survival, differentiation, and virulence by catalyzing the reversible interconversion of carbon dioxide (CO₂) and bicarbonate (HCO₃^-). Herein, we report the biochemical and crystallographic characterization of the β-CA CafA from the fungal pathogen Aspergillus fumigatus, the main causative agent of invasive aspergillosis. CafA exhibited apparent in vitro CO₂ hydration activity in neutral to weak alkaline conditions, but little activity at acidic pH. The high-resolution crystal structure of CafA revealed a tetramer comprising a dimer of dimers, in which the catalytic zinc ion is tetrahedrally coordinated by three conserved residues (C119, H175, C178) and an acetate anion presumably acquired from the crystallization solution, indicating a freely accessible "open" conformation. Furthermore, knowledge of the structure of CafA in complex with the potent inhibitor acetazolamide, together with its functional intolerance of nitrate (NO₃^-) ions, could be exploited to develop new antifungal agents for the treatment of invasive aspergillosis.

• 대한가정학회지
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• 제25권4호
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• pp.1-8
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• 1987

The effects of Aspergillus niger H-18(AN) and A.fumigatus E-29(AF) on the deterioration of test materials were examined. 1. When the fungi were inoculated to the cotton fibers placed on Czapeck agar, malt extract agar, and potato agar, they grew best on potato agar which in that context was chosen as a basal medium for deterioration studies. The tensile strength of ontton fiber on which AN was grown for 30 days decreased by 33.9% with a concommitant increase in elongation by 43.1%. 2. Cotton fabric lost the weight by 1.35%, when inoculated with AN while it lost the weight by 0.86% when inoculated with AF. 3. When AN and AF were inoculated separately on cotton fibers, tensile strength decreased by 52.8% and 43.3%, respectively, with concommitant increases in elongation by 34.2% and 29.4%, respectively. 4. The cotton was damaged more severely by AN than AF, when they were observed by scanning electron microscope.

• 대한가정학회지
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• 제31권2호
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• pp.213-219
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• 1993

Aspergillus fumigatus(AF) and Penicillum citrinum(PC) were selected for their strong abilities to produce protease. The result are summarized as follows; 1. The λd numerical values of the silk fabrics with AF and PC were 560 and 580 nm for the both stains of molds. 2. By the growth of molds, lightness, original color scale, and grey scale of the fabrics gradually decreased while chroma increased. 3. The minimum inhibitory concentrations of mold proofing agents, such as Leperon WL, 8-hydroxyquinoline copper acetates, trimethylol melamine and dimethly ethylene urea was 50 ppm. 4. Glycoxale was not effective at the abovely concentration. Since Leperon WL, dimethyl ethylene urea effectively inhibited the growth of PC silk, tensile strengh and elongation of the fabrics were not changed.

• 대한가정학회지
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• 제30권2호
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• pp.53-60
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• 1992

The effects of Aspergillus fumigatus(AF) and Penicillium citrinum(PC) deterioration of test materials were examined. When the fungi were inoculated to the silk fibers placed on Czapeck agar, malt extract agar and potato agar, they grew best on potato agar which in that context was chosen as a basal medium for deterioration studies. The tensile strength of silk fiber on which AF was grown for 30 days decreased by 28.5% with a concommitant increase in elongation by 40.1%. Silk fabric lost the weight by 4.74%, when inoculated with AF while it lost the weight by 3.37%, when inoculated with AF. When AF and PC were inoculated separately on silk fibers, tensile strength decreased by 76.3% and 56.4%, respectively, with concommitang increases in elingation by 53.1% and 37.8% respectively. The silk was damaged more severely by AF than PC, when they were observed by scanning electron microscope.

• 한국응용과학기술학회지
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• 제2권2호
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• pp.15-20
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• 1985

Influence of vitamins on the felt and lipid production of Aspergilus niger var. macrosporus, Aspergillus fumigatus and penicillium notatum were investigated after 10 days of incubation at $30^{\circ}C$ under static culture condition. The felt of molds were lower in the media containing vitamins than control medium. The lipids produced by each strains were highest yields in media containing vitamins. Among of these Aspergillus niger var. macrosporus and Aspergillus fumigatus produced. 4.6g and 5.28g in medium containing inositol 2.5mg/l and 0.5mg/l, respectively; while Penicillium notatum produced 1.51g in a medium containing thiamine 10mg/l. The major fatty acid of lipids were palmitic acid, stearic acid, oleic acid and linoleic acid. Aspergillus niger var. macrosporus was lower palmitic acid in media containing vitamins than control medium, While linoleic acid was higher in media containing thiamine and inositol. Aspergillus fumigatus was lower oleic acid in media containing vitamins than control medium, While linoleic acid was higher in media containing vitamins. Peniillium notatum was lower palmitic acid, oleic acid and stearic acid in media containing vitamins but linoleic acid was higher. The composition of fatty acid of lipids changed depending on the media containing vitamins but hardly found a certain tendency except linoleic acid which was higher in a media containing thiamines and inositols. The degree of unsaturation of fatty acids in the lipids were comparatively higher in media containing vitamins than control medium.

• 대한임상검사과학회지
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• 제41권4호
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• pp.158-166
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• 2009

On the basis of morphological characteristics, of total 128 strains of from sputum of tuberculos inpatient were identified as A. fumigatus (61 strains), A. niger (37), A. flavus (26), A. versicolor (1), A. nidulans (1), A. clavatus (1) and Neosartorya fennelliae (1). These strains were re-identified according to recent Aspergillus classification system which is mainly based on molecular characteristics. The strains were grouped by randomly amplified polymorphic DNA (RAPD) techniques. The representative strains from each group were sequenced with partial ${\beta}$-tubulin gene and compared with those of reference strains in the Aspergillus and were identified by the sequence. The identification was confirmed by morphology examination. As the results, they are reidentified as A. fumigatus (58), A. niger (11), A. tubingensis (26), A. flavus (27), A. sydowii (3), A. nidulans (1), A. clavatus (1) and Neosatorya fennelliae (1). This is the first report of A. tubuingensis in clinical field in Korea.

• 대한수의사회지
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• 제41권5호
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• pp.421-425
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• 2005