• Korean Journal of Microbiology
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• v.31 no.4
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• pp.300-305
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• 1993

Neurospora crassa accumulated cadmium. iron, manganese and lead in the mycelium. The growth of N. crassa was inhibited in the presence of cadmium but not in the presence of iron or manganese. In the presence of lead. the growth of N. crassa was accelerated. In the presence of cadmium. mycelium became thick and a conidiospore grew into a mycelial ball instead of normal threadlike gro~1h. Each metal wa'i accumulated in different subcellular organelles bound to protein and induced different proteins.

• Microbiology and Biotechnology Letters
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• v.19 no.3
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• pp.281-289
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• 1991

Neurospora crassa (KCTC 6079) produces tyrosinase (EC 1.14.18.1) during sexual differentiation under derepressed conditions in the presence of inducers such as amino acid analogues, antimetabolites or protein synthesis inhibitors. The selection of inducer concentration and induction time as well as inducer type are critical for the optimization of the enzyme production. The best inducer was found to be cycloheximide. Since cycloheximide was toxic to the cells, an optimal inducer concentration and an optimal induction time were determined to maximize the enzyme production from batch cultures. Mathematical models for the cell growth and the enzyme production were proposed and used for process optimization. By optimizing the induction conditions, maximum tyrosinase productivity was increased significantly.

• Korean Journal of Microbiology
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• v.40 no.2
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• pp.73-80
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• 2004

Coenzyme Q is a quinone derivative that acts as a lipid electron carrier in the respiratory chain located at mito-chondrial inner membrane in eucaryotes or plasma membrane in procaryotes and also functions as antioxidant. A putative Neurospora crassa coq-4 gene was cloned and functionally expressed in Saccharomyces cerevisiae coq4 mutant. Complemented S. cerevisaie mutant strain was able to produce coenzyme $Q_{6}$ and showed a normal growth rate. They also showed less sensitivities to polyunsaturated fatty acids such as linoleic acid or linolenic acid. The predicted sequence of N. crassa COQ4 is consisted of 347 amino acids with a molecular mass of 39.7 kDa and showed 35% identity and 52% similarity with that of S. cerevisiae.

• Journal of Life Science
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• v.13 no.2
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• pp.191-196
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• 2003

The ars gene of the Neurospora crassa encodes arylsulfatase and is expressed under sulfur limitation. An ars-1 promoter(Pars) translationally-fused to a lacZ gene was transformed into the N. crassa RLM 35-35, a his-3 inl strain and integrated into the his-S locus by a single crossover homologous recombination. $\beta$-galactosidase specific activity was measured from mycelia grown in sulfur-limited Vogel's medium. Enzyme activity reached its maximum at 14 hour after the shift to derepressing condition. When activity from homokaryon generated by microconidiation was measured, it was 17% a higher than that from heterokaryon.

• Environmental Analysis Health and Toxicology
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• v.8 no.1_2
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• pp.11-17
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• 1993

Radioactive elements Li/sup +/, Rb/sup +/and Cs/sup +/ effect the period shortening in proportion to the higher concentration on the growth of Neurospora crassa. 1 mM LiCl presented the result of the period length 0.52 h shorter than average circadian rhythm 21.66 h. 1 mM RbCl reduced the period length 1.13 h than control period 21.89 h and 1 mM CsCl reduced 2.12 h than control period 21.89 h. In the equal concentration Cs/sup +/ had an extreme effect. Fatal doses of Li/sup +/, Rb/sup +/ and Cs/sup +/ are 20mM, 30mM and 20mM. In the fatal concentration Neurospora didn't develop more after 7 days and the formation of spores were not given in regular order. Circadian length of Neurospora decreased generally at the last cycle of the growth.

• Journal of Life Science
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• v.13 no.6
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• pp.933-942
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• 2003

CoenzymeQ is a quinone derivative with a long isoprenoid side chain. It transports electrons in the respiratory chain located in the inner mitochondrial membrane of eukaryotes and the plasma membrane of prokaryotes. It also functions as an antioxidant. Saccharomyces cerevisine coq mutants, that are deficient coenzyme Q biosynthesis fail to aerobically grow. They are not able to grow on non-fermentable carbon sources, such as glycerol, either The putative $coq^{-7}$ gene involved in coenzyme Q biosynthesis of Neurospora crassa was cloned and used for complementation of S. cerevisiae coq7 mutant. The predicted amino acid sequence of N. crassa COQ7 showed about 58% homology with Coq7p of S. cerevisiae. The growth rate of S. cerevisiae $coq^7$ mutant transformed with the N. crassa $coq^{-7}$ gene was restored to the wild-type level. The complemented 5. cerevisiae strain was able to grow with glycerol as a sole carbon source and showed less sensitivities to linolenic acid, a polyunsaturated fatty acid.

• Korean Journal of Microbiology
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• v.26 no.2
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• pp.73-81
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• 1988

$\alpha$-Amylase (EC.3.2.1.1) of Neurospora crassa (ATCC9279) was cloned in E. coli HB101 using shotgun method, and the enzymes isolated from both N. crassa and E. coli were compared. Chromosomal DNA isolated from the spores of N. crassa was partially digested with PstI restriction endonuclease and rejoined to pBR322 which had been digested with the same enzyme. The resulting recombinant DNA were introduced into E. coli HB101 which had competancy by treating with $CaCl_{2}$. As the result, about 8000 colonies which showed tetracycline resistance were selected and two of the colonies which had 13.5Kb recombinant plasmid exhibit starch degrading activity on starch-containing plate when treated with D-cycloserine. $\alpha$-Amylases from both N.crassa and E. coli were isolated by using ammonium sulfate precipitation, DEAE-cellulose ion exchange column chromatography and Bio-Gel P150 gel foltration column. As the result, about 81.3 fold and 5.6 fold purifications in specific activities were obtained respectively, and specific activities of the gel filtrates were 6.1u/mg and 85u/mg respectively. The properties of both enzymes were compared and they showed quite the similar patterns in optimal temperature, optimal pH and had same molecular weight about 100,000 daltons on gel filtration method. Optimal temperatures for both enzymes were $70^{\circ}C$ and optimal pH were about 6 and 10.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.476-476
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• 2012

Although plasma is an efficient means of microbial sterilization, mechanism of plasma effect on microorganisms still needs to be clarified. In addition, a limited number of studies are available on eukaryotic microorganisms such as yeast and fungi in relation to plasma application. Thus, we investigated cellular and molecular aspects of plasma effects on a filamentous fungus, Neurospora crassa by making use of argon plasma jet at atmospheric pressure. The viability and cell morphology of N. crassa spores exposed to plasma were both significantly reduced depending on the exposure time when treated in water. The intracellular genomic DNA content was dramatically reduced in fungal tissues after a plasma treatment and the transcription factor tah-3 was found to be required for fungal tolerance to a harsh plasma environment.

• Korean Journal of Microbiology
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• v.32 no.2
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• pp.132-138
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• 1994

L-Ascorbic acid-producing enzyme in Neurospora crassa was found to exist in mitochondria and the activity of this enzyme was increased by the addition of D-fluconno-${\gamma}$-lactone or L-gulono-${\gamma}$-lactone in the media. L-Ascorbic acid-producin enzyme in N. crassa has been purified with ammonium sulfate precipitation. DEAE Sepharose CL-6B ion exchange chromatography. Sephacryl S-200 gel filtration chromatography and Reactive yellow 3-agarose dye affinity column chromatography. The specific activity of this enzyme was increased to 239.6 fold and the yield was 2.1%. The molecular weight of the native enzyme was 150.000 dalton when it was estimated with Sephacryl S-200 gel filtration chromatography. Its molecular weight appeared as 75.000 dalton by SDS-polyacrylamide gel electrophoresis. which suggested that this enzyme was consisted with two identical subunits. The optimal pH for this enzyme was 9.0 and the $K_m$ value for D-galactono-${\gamma}$-lactone was 0.073 mM.

• Environmental Analysis Health and Toxicology
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• v.10 no.3_4
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• pp.7-13
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• 1995

The most periodlengths($\tau$) of conidiation of Neurospora were shortened in the medium with Li$^+$, Rb$^+$, and Cs$^+$ under the blue or green light. The higher the concentration of the heavy metal elements are, the shorter the circadian lengths are. The largest differences between the maxima- and minima circadian lengths showed in the medium with LiCI, RbCl, and CsCI under the blue lights at 150 Lux, while the little differences of circadian lengths presented in 1 mM heavy metal elements at the 270Lux blue light. Li$^+$ under the blue light effected extremely much and in the order of Rb$^+$ and Cs$^+$ on the conidiation of Neurospora. Under the green lights at 270Lux, the smallest changes of the circadian lengths are resulted in the medium with heavy metal elements. The other way at the green light 150Lux, the conidiation is stimulated by lmM LiCI or RbCl for the average 0.71h and 0.29h longer than the periodlength of control 28.34h. The medium with Li$^+$ under the green light has less effect on the conidiation rhythm of Neurospora than with Rb$^+$ or Cs$^+$.