• 한국미생물·생명공학회지
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• 제7권3호
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• pp.141-147
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• 1979

Aspergillus nidulans가 생산하는 naringinase를 DEAE-Sephadex A-25를 사용하여 이온결합법으로 고정화시키는 조건과 그 고정화효소의 성질 및 column reactor 에서의 연속 반응에 대하여 연구 검토한 것을 요약하면 다음과 같다. 고정화 효소를 조제할 때에 효소가 담체에 흡착되는 최적 pH는 6.0이었고 건조된 담체 1g에 대해 이상적인 수용성 효소의 량은 110 units이였다. 고정화 naringinase의 반응 최적 온도와 pH 는 각각 5$0^{\circ}C$와 7.0이며, 그 pH 안정성과 열 안정성은 수용성 효소보다 모두 높았다. 고정화 naringinase의 활성화 에너지는 Arrhenius plot에 의해 7.96kca1/mo1e이었고 겉보기 Km 값은 5.88$\times$$10^{-4}$M 이었다. 고정화 naringinase를 column 내에서 연속 반응시킬 때 Bar-Eli등의 Michaelis-Menten식의 적분형을 변형하여 유속과 가수분해도의 관계를 검토한 결과, 유속이 증가하면 가수분해도가 감소되었고 동시에 겉보기 Km값도 감소하였다. 또한 반응량 (colum reaction capacity)은 유속이 증가함에 따라서 서서히 감소하였다.

• 한국균학회지
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• 제17권4호
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• pp.209-213
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• 1989

사철 느타리 버섯 Uracil 요구성 균주를 Aspergillus nidulans ans 1과 Neurospora crassa pyr 4 유전자를 지닌 백터를 이용하여 형질전환시켰다. 사철 느타리버섯 ura 요구성 균주의 원형질체를 pyr 4 유전자를 지닌 백터 pDJB3과 혼합 후 PEG와 $CaCl_2$를 처리하였다. 형질전환 균주는 버섯 최소배지에서 안정되게 생육하였고 southern hybridization 결과도 백터 DNA가 사철 느타리 염색체에 삽입되었다. 형질전환 균주는 단핵성이므로 다른 단핵 균사와 균사 융합 후 자실체 형태, 포자형성 등을 조사하였다. 형질전환이 안된 균주는 톱니형 자실체를 형성한데 비해 형질전환된 균주는 톱니형, 깔대기형, 우산형, 갓 미발육형의 자실체를 형성하였다.

• 대한수의학회지
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• 제24권1호
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• pp.36-39
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• 1984

The present survey was undertaken to determine the mycoflora of broiler houses. Attempts were made to isolate and identify fungi in the dust, feed, litter and water from 21 broiler houses. A total of 166 isolates of fungi was identified as yeast spp. (44%), Aspergillus spp. (30.7%), Verticillium spp. (7.2%), Penicillium spp. (3.6%), Paecilomyces spp. (3.6%), Scopulariopsis spp. (3.0%), Cephalosporium spp. (3.0%), Chrysosporium spp. (2.4%), Cladosporium spp. (1.8%) and Absidia spp. (0.6%). Isolated of Aspergillus(A) spp. and Penicillium(P) spp. were identified as A. fumigatus, A. flavus, A. terreus, A. nidulans, A. niger, P. citrinum and P. palitan. Fungal contamination of the broiler houses predominated in the dust. The important point is that must of the isolates were pathogenic fungi.

• Mycobiology
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• 제36권1호
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• pp.1-9
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• 2008

Sixty three species and 5 varieties belonging to 30 fungal genera were collected from 75 soil samples. Cultivated (29 genera and 58 species + 5 var.), desert (22 and 35 + 2 var.) and saline soil (21 and 41 + 1 var.) fungi were recovered on glucose-, cellulose- and 50% sucrose-Czapek's agar at $28^{\circ}C$. The most common genera were Alternaria, Aspergillus, Emerieella, Fusarium, Mycosphaerella, Nectria and Penicillium. The most prevalent species from the three types of soils on the three types of media were Alternaria alternata, Aspergillus flavus, A. fumigatus, A. niger, A. terreus, Emerieella nidulans, Fusarium oxysporum, Myeosphaerella tassiana, Nectria haematococca and Penicillium ehrysogenum. Chaetomium globosum was in the top of fungi in producing endo-$\beta$-1,4-glucanases among the 42 tested isolates obtained from soils on cellulose-Czapek's agar. Maximum production of this enzyme by C. globosum obtained after 6 days of incubation at $30^{\circ}C$ with culture medium containing maltose as a carbon source and ammonium nitrate as a nitrogen source and pH initially adjusted to 6.

• Animal cells and systems
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• 제5권3호
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• pp.225-229
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• 2001

Nek2 is a mammalian protein kinase that is structurally homologous to NIMA, a mitotic regulator in Aspergillus nidulans. To understand cellular processes in which Nek2 participates during mammalian development, we investigated the expression and subcellular localization of Nek2 in vivo. The Nek2 protein was detected in spermatocytes and in a fraction of actively dividing ovarian follicle cells and of embryonic tissues. We also observed that Nek2 was localized in both the nucleus and centrosome in embryonic cells. Such localization pattern supports the proposal that Nek2 is a mitotic regulator that is involved in multiple cell cycle events during mammalian development.

• Mycobiology
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• 제31권3호
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• pp.157-161
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• 2003

Various soil samples were collected from twenty-four areas of ten different poultry farms in Korea and screened for prevalence of keratinolytic fungi. Fourteen species of feather-associated fungi belonging to ten genera Acremonium, Alternaria, Aspergillus, Cladosporium, Curvularia, Fusarium, Monascus, Mucor, Penicillum, and Verticillium isolated from poultry soils were grown on keratin medium. Especially, Aspergillus spp. populations associated with the soil sample is $1{\times}10^5$ cfu/g. A. flavus, A. fumigatus, A. niger, A. nidulans, and A. terreus could utilize keratin of chicken feather and degrade it, producing sulphydryl-containing compounds detected as keratinase, cysteine and total proteins. Keratinolytic activities of five Aspergillus species also changed the pH of the medium more alkaline than those that were less keratinolytic.

• Animal cells and systems
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• 제6권2호
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• pp.181-181
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• 2002

Nek2 is a mammalian protein kinase that is structurally homologous to NIMA, a mitotic regulator in Aspergillus nidulans. We recently observed that the Nek2 protein was localized in multiple sites within a cell in a cell cycle state-specific manner. This suggests that Ndk2 is involved in diverse cellular functions during the cell cycle progression. To have a better understanding on cellular functions in which Nek2 participates, we carried out yeast two-hybrid screening and isolated six candidate clones whose products interact with Nek2. Most of Nek2-interacting proteins (NIPs) appear cytoplasmic, suggesting that Nek2 is involved in cellular functions in cytoplasm. Further experiments are under progress to confirm their interactions with Nek2 and to understand their biological significance.

• Journal of Microbiology and Biotechnology
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• 제13권1호
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• pp.146-148
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• 2003

Effects of propylamine on conidial head formation and growth of Aspergillus niger and Aspergillus oryzae were analyzed. Propylamine inhibited conidial head formation in these two fungi, and the inhibitory effect of propylamine was not suppressed by the addition of potassium chloride at high concentration, which promotes conidial head formation in A. nidulans and A. oryzae. Propylamine also inhibited the growth of A. niger and A. oryzae by $41\%\;and\;32\%$, respectively, when the concentration of propylamine was $2\%$.

• Mycobiology
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• 제29권3호
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• pp.132-134
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• 2001

Since it is known that Agrobacterium tumefaciens, which has long been used to transform plants, can transfer the T-DNA to yeast Saccharomyces cerevisiae during tumourigenesis, a variety of fungi were subjected to transformation to improve their transformation frequency. In this study, I report the A. tumefaciens-mediated transformation of filamentous fungus Aspergillus niger. Transfer of the binary vector pBIN9-Hg, containing the bacterial hygromycin B phosphotransferase gene under the control of the Aspergillus nidulans trpC promoter and terminator as a selectable marker, led to the selection of $50{\sim}100$ hygromycin B-resistant transformants per $1{\times}10^7$ conidia of A. niger. This efficiency is improved $10{\sim}20$ fold more than reported elsewhere. In order to avoid the difficulties in selection transformant from the over-growing non-transformant, I used top agar containing 900 ${\mu}g/ml$ of hygromycin. Genomic PCR and Southern analysis showed that all transformants contained single T-DNA insert per fungal genome. This technique offers an easier and more efficient method than that of using protoplast.

• Mycobiology
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• 제36권3호
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• pp.167-172
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• 2008

Beef luncheon meat is one of the most popular meals in several countries in the world including Egypt. Thirty one fungal species and 3 species varieties were recovered from 30 samples of beef luncheon meat collected from different supermarkets in Qena. Alternaria, Aspergillus, Emericella, Mucor, Mycosphaerella, Penicillium and Rhizopus were the most common genera on the two types of media. From the above genera, the most prevalent species were Alternaria alternate, Aspergillus flavus, A. fumigatus, A. niger, A. terreus, Emericella nidulans, Mucor racemosus, Mycosphaerella tassiana, Penicillium chrysogenum and Rhizopus stolonifer. Screening of fungi for their abilities to produce lipase enzyme showed that, ten isolates represented 32.26% of total isolates appeared high lipase production, while sixteen isolates (51.61%) were moderate and 5 isolates (16.13%) were low producers. Aspergillus niger, Fusarium oxysporum and Nectria haematococca produced the highest amount of lipase enzyme, so these fungi were used in further studies. The incorporation of five food preservatives (Disodium phosphate, sodium benzoate, citric acid, potassium sorbate and sodium citrate) individually in the culture medium of lipase production exhibited an inhibitive effect on the mycelial growth and enzyme production by Aspergillus niger, Fusarium oxysporum and Nectria haematococca.