• Proceedings of the Microbiological Society of Korea Conference
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• 2003.05a
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• pp.51-54
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• 2003

Analysis of the Neurospora crassa genome data reveals at least 14 proteins that contain tetratricopeptide repeat (TPR) motifs. One of them shows over $60\%$ homology with SSN6 of Saccharomyces cerevisiae, a global repressor that mediates repression of genes involved in various cellular processes. Sequence analysis of its cDNA shows that it encodes a putative 102kDa protein. Mutant strains generated by RIP (repeat induced point mutation) process show four distinctive patterns of vegetative growth at various rates. They are male-fertile, yet all female-sterile and produced little or no perithecium. These results indicate that this gene is pleiotropic and involved in several cellular processes of vegetative growth, conidiation and sexual cycle. It is designated rcm-1(regulation of conidiation and morphology).

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.204.4-204
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• 2005

• Journal of Photoscience
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• v.5 no.2
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• pp.73-81
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• 1998

Light signals constitute major factors in regulating gene expression and morphogenesis in plants and fungi. Phytochrome A and B were well characterized red and far-red light receptors in plants. Red light signals increased the phosphorylation of 18 kDa protein, which was identified to be nucleoside diphosphate (NDP) kinase. The NDP kinase catalyzed autophosphorylation and had a protein kinase activity similar to MAP (mitogen activated protein) kinase. As candidates for blue light photoreceptors, cDNAs for CRY1 and CRY2 were isolated. The N-teminal regions of these proteins showed a high hornology to DNA photolyase. The 120 kDa protein first detected in Pisurn sativurn, which showed blue light induced phosphorylation was also detected in Arabidopsis thaliana. The 120 kDa protein was encoded by the nphl gene, which regulated positive phototropism of the plant. In Neurospora crassa, blue light irradiation of the membrane fraction prepared from roycelia stimulated the phosphorylation of the 15 kDa protein, which was also identifmd to be an NDP kinase. Recent progress in understanding early events in light signal transduction mainly in Pisum sativum Alaska, Arabidopsis thaliana and Neurospora crassa was summarized.

• Korean Journal of Environmental Biology
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• v.24 no.4
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• pp.329-336
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• 2006

Distribution of zooplankton communities was sampled vertically with a NORPAC net investigated in costal area of Wando from 30, August at 7 stations. A total of 37 taxa were sampled with a total abundance of zooplankton ranged from $147{\sim}1,696indiv.\;m^{-3}$. Evadne tergestina, Acartia pacifica, Paracalanus parvus s. 1, Decapod larvae, Sagitta crassa were dominant species in coastal area of Wando and they contributed 90% of mean abundance of total zooplankton. Multivariate analysis revealed significant differences in community structure among the three regions: the site 1 (A), the middle part of the sampling area (B) and other sites (C). The number and abundance of zooplankton varied significantly among the three regions (p < 0.05). Of these, the distribution of zooplankton communities in the coastal area of Wando was controlled by Tsushima Warn Current and bottom cold water of Yellow Sea.

• Journal of Microbiology
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• v.44 no.5
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• pp.556-561
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• 2006

A differential display for the expression profiles of wild-type Cryphonectria parasitica and its virally-infected isogenic hypovirulent strain revealed several transcripts of interest, which evidenced significant matches with fungal genes of known function. Among which, we have further analyzed an amplified PCR product with significant sequence similarity to the known fungal stress-responsive thioredoxin gene from Neurospora crassa. The product of the cloned thioredoxin gene, CpTrx1, consists of 117 amino acids, with a predicted molecular mass of 13.0 kDa and a pI of 5.4. Sequence comparisons demonstrated that the deduced protein sequence of the CpTrx1 gene evidenced a high degree of homology to all known thioredoxins, with the highest degree of homology with trx1, a thioredoxin gene from Saccharomyces cerevisiae, and evidenced a preservation of the conserved hall markresidues (Trp-Cys-Gly-Pro-Cys) at the active site of thioredoxin. The E. coli-generated CpTRX1 manifested thioredoxin activity, according to the insulin reduction assay, which indicates that the cloned gene does indeed encode for the C. parasitica thioredoxin.

• Journal of Microbiology and Biotechnology
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• v.15 no.1
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• pp.22-28
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• 2005

Gibberellins (GAs) play important roles in plant growth and development. Fifty-four fungi were isolated from the roots of 4 kinds of Sesamum indicum plants, and the production of GAs was spectrophotometrically examined. The number of GA-producing fungi was two strains from S. indicum, four strains from Gold S. indicum, and five strains from Brown S. indicum. Eleven fungi with GAs-producing activity were incubated for seven days in 40 ml of Czapek's liquid medium at $25^{\circ}C$ and 120 rpm, and the amount of each GA in the medium was measured by gas chromatographymass spectrometery (GC-MS). Penicillium commune KNU5379 produced more $GA_3$, $GA_4$, and $GA_7$ than Gibberella fujikuroi, Fusarium proliferatum, and Neurospora crassa which are known as GAs-producing fungi. GAs-producing activity of the P. commune KNU5379 was shown to produce 71.69 ng of $GA_1$, 252.42 ng of $GA_3$, 612.00 ng of $GA_4$, 259.00 ng of $GA_7$, and 202.69 ng of $GA_9$ in 25 ml of liquid medium. Bioassay of culture fluid of GA-producing fungi was also performed on rice sprout.

• Journal of Microbiology
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• v.43 no.6
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• pp.475-486
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• 2005

Fungal secondary metabolites constitute a wide variety of compounds which either playa vital role in agricultural, pharmaceutical and industrial contexts, or have devastating effects on agriculture, animal and human affairs by virtue of their toxigenicity. Owing to their beneficial and deleterious characteristics, these complex compounds and the genes responsible for their synthesis have been the subjects of extensive investigation by microbiologists and pharmacologists. A majority of the fungal secondary metabolic genes are classified as type I polyketide synthases (PKS) which are often clustered with other secondary metabolism related genes. In this review we discuss on the significance of our recent discovery of chalcone synthase (CHS) genes belonging to the type III PKS superfamily in an industrially important fungus, Aspergillus oryzae. CHS genes are known to playa vital role in the biosynthesis of flavonoids in plants. A comparative genome analyses revealed the unique character of A. oryzae with four CHS-like genes (csyA, csyB, csyC and csyD) amongst other Aspergilli (Aspergillus nidulans and Aspergillus fumigatus) which contained none of the CHS-like genes. Some other fungi such as Neurospora crassa, Fusarium graminearum, Magnaporthe grisea, Podospora anserina and Phanerochaete chrysosporium also contained putative type III PKSs, with a phylogenic distinction from bacteria and plants. The enzymatically active nature of these newly discovered homologues is expected owing to the conservation in the catalytic residues across the different species of plants and fungi, and also by the fact that a majority of these genes (csyA, csyB and csyD) were expressed in A. oryzae. While this finding brings filamentous fungi closer to plants and bacteria which until recently were the only ones considered to possess the type III PKSs, the presence of putative genes encoding other principal enzymes involved in the phenylpropanoid and flavonoid biosynthesis (viz., phenylalanine ammonia-lyase, cinnamic acid hydroxylase and p-coumarate CoA ligase) in the A. oryzae genome undoubtedly prove the extent of its metabolic diversity. Since many of these genes have not been identified earlier, knowledge on their corresponding products or activities remain undeciphered. In future, it is anticipated that these enzymes may be reasonable targets for metabolic engineering in fungi to produce agriculturally and nutritionally important metabolites.

• Korean Journal of Environmental Biology
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• v.17 no.4
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• pp.529-541
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• 1999

In order to elucidate characteristics of water quality, investigation of monthly dynamics of environmental factors and algal populations at major four stations of the mid and lower part in Taechong Reservoir was performed from June 1998 to June 1999. Water temperature, DO and pH were ranged 5.3~27.7$^{\circ}C$, 6.2~13.8 mgO$_2$/1 and 6.4~9.5, respectively. Those were varying as the season changes. Among inorganic nitrogen nutrients, NH$_4$was ranged from 5.5% to 7.2% of NO$_3$and NO$_3$was almost same through the seasons except summer in which it was low. SRP and SRSi were increased in summer when the blue-green algae became dominant. Those were decreased as the cell density of diatom increased when the water temperature dropped. Therefore SRSi was considered to be another important nutrient factor contributing to the increment of biomass of freshwater algae as well as SRP. Average chi-$\alpha$ concentration ranged from s to 12 $\mu$g/1 and in the lower part or the reservoir, the lowest was found. Moreover, there were remarkable increment in summer when TN/TP ratio were decreasing from relationships between TN/TP ratio and chi-$\alpha$ concentration. Annual mean ratio of TN/TP ratio was relatively high as the value was 110, which was relatively high, and it showed that P is the dominant factor in the algal growth. The dynamics of phytoplankton were simply dominated by a few species seasonally. In summer, blue -green algae such as Anabaena, Microcystis and Oscillatoria were dominant and algal bloom of blue -green began from early summer, sustained to late autumn. The average standing crops of A. spiroides v. crassa, M. aeruginosa and O. limosa were ranged 0.3~2.0$\times$10$^4$cells/ml, 6.4$\times$10$^2$~1.0$\times$10$^4$cells/ml and 4.6$\times$10$^3$~1.6$\times$10$^4$cells/ml, respectively. In winter, diatom Stephanodiscus was considered to be an important species whose average standing crops of Stephunodiscus was 4.9$\times$10$^2$cells/ml from November to April of the next year and the highest was 1.3$\times$10$^3$cells/ml in January.

• The Korean Journal of Mycology
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• v.32 no.1
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• pp.16-22
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• 2004

The gibberellins (GAs) play important roles in plant growth and development. Twenty three fungi were isolated from the roots of Lindera obtusiloba and Vaccinium koreanum. The numbers of GA-producing fungi were six strains from Lindera obtusiloba and four strains from Vaccinium koreanum. The fungi with GAs-producing activity were incubated for seven days in 40 ml of Czapek's liquid medium at $25^{\circ}C$, 120 rpm, and the amount of each GA in the medium was measured by gas chromatography-mass spectrometer (GC-MS) to determine the productivity of GAs. Penicillium griseofulvum KNU5379 produced more GA in case of $GA_{3}$ than Neurospora crassa known as a GAs-producing fungus. P. griseofulvum KNU5379 was shown to produce $GA_1\;9.79\;ng,\;GA_3\;133.58\;ng,\;GA_4\;2.64\;ng,\;GA_7\;7.80\;ng\;and\;GA_{53}\;0.73\;ng$ in 25 ml of liquid medium. Bioassay using culture fluid of GAs-production fungi was performed on rice sprout.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.4
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• pp.251-264
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• 1992

Distribution of indicator species of copepods and chaetognaths were studied as an indicator species of water mass in the southeastern area of the Yellow Sea. Undinula darwini, Lucicutia flavicornis, Pleuromamma gracilis, Euchaeta resselli, Euchaeta plane and Sagitta enflata were found to be reliable indicator species for determining warm water mass. Of these species, E. plana and E. rusrelli have a weak tolerance on the low temperature. Sagitta crassa was indicator species of neritic waters; Sagitta bedoti was that of mixing waters. Centropages abdominalis represented neritic cold waters. In February, U darwini, L. flavicornis, P. gracilis, E. russelli, E. plana and S. enflata occurred in the western waters of Cheju-Do where warm waters over $14^{\circ}C$ occupied. Centropages abdominalis occurred in the northern area beyond Chindo with water temperature less than $10^{\circ}C$. E. plana, E. russelli and S. bedoti were found at the regions between Cheju-Do and Chindo where the water temperature was $12- 14^{\circ}C$ corresponding to the mixing waters. Based on cluster analysis and T-S diagram in February three different water masses were identified from the south to the north. In August, water masses were analyzed at two different layers, 0-20m and 20m- bottom layers, separated by bhermocline depth. In 0-20m layer, E. plana and E. russelli were found from the western waters of Cheju-Do to Daehuksando. In 20m- bottom layer, E. russelli and E plena occurred at the northwestern waters of Cheju-Do with the water temperature warmer than $12^{\circ}C.\;C.$ abdominalis was found at the northern area beyond Chindo. Based on the cluster analysis and T-S diagram in August three different water masses at 0-20m and 20m-bottom layers were identified from the coast to the offshore. C. abdominalis was found at the adjacent water of Chindo at 0-20m layer and the northern area beyond Chindo at 20m~bottom layer. This fact suggested that the cold water mass existed at tile adjacent waters of Chindo in summer.