• Microbiology and Biotechnology Letters
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• v.7 no.3
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• pp.141-147
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• 1979

Naringinase from Atpergillus nidulans was immobillized on DEAE-Sephadex A-25 and its characteristics were studied. The optimal conditions for the preparation of the immobilized enzyme were as follow; optimal pH, incubation time and the suitable amount of enzyme were 6.0, 30 min. and 110 units per gram of the dried ion exchage resin, respectively. The optimal pH of the immobilized enzyme was higher than that of the native enzyme. The optimal temperature increased from 4$0^{\circ}C$ to 5$0^{\circ}C$. The heat and pH stability of the immobillized enzyme were better than those of the native enzyme. No significant difference in the Michaelis constant was detected. Activation energy of the immobilized enzyme was 7.96 Kcal/mole, and the apparent Michaelis rate equation was used to describe the action of this material. The degree of hydrolysis was dependant on the flow rate at low rate of perfusion through the column. As the flow rate increased, the value of the apparent Km decreased.

• The Korean Journal of Mycology
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• v.17 no.4
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• pp.209-213
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• 1989

Transformation of an auxotrophic requirement for uracil in Pleurotus florida P101 has been achieved using chimeric vector containing Aspergillus nidulans ans 1, and Neurospora crassa pyr 4 DNA. Protoplasts of $Ura^-$strains of P. florida were incubated with plasmid pDJB3 containing the cloned pyr 4 gene in the presence of polyethylene glycol and $CaCl_2$. Transformants could grow on MMM showing mitotical stability. Southern hybridization analysis of DNA isolated from transformants showed that the Neurospora pyr 4 gene and vector sequence might be integrated into the P. florida chromosomes. As the transformants were monokaryon, each transformant was mated with the other monokaryon. Fruitbody shape of untransformant was eroded type but those of transformants were eroded type, funnel type, plane type and ungrowing cap type.

• Korean Journal of Veterinary Research
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• v.24 no.1
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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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• v.36 no.1
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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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• v.5 no.3
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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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• v.31 no.3
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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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• v.6 no.2
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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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• v.13 no.1
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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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• v.29 no.3
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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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• v.36 no.3
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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.