• Journal of Microbiology
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• v.34 no.4
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• pp.311-315
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• 1996

The retroviral Gag polyprotein directs the assembly of virion particles and plays an important role in some events after entry into a host cell. The Gag polyprotein of a virus mixture is responsible for inducing murine acquired immunodeficiency syndrome (MAIDS) when injected into susceptible strains of mice. In order to identify the host cellular proteins which interact with the MAIDS virus Gag proteins and possibly mediate the function of the Gag proteins, mouse T-cell leukemic cDNA expression library was screened using the yeast GAL4 two hybrid system. Of 11 individual positive clones, the clone Y1 was selected for the study of protein-protein interaction. Its DNA sequence revealed that it was an exact match to the murine SH3 domain-containing protein SH3P8. It is expressed as 2.4 kbp transcripts in testis at higher levels and in various tissues tested at lower levels. Glutathione S-transferase-Y1 fusion protein binds tightly to $Pr60^{def-gag}$ as well as $Pr65^{eco-gag}$.

• Korean Journal of Microbiology
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• v.24 no.2
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• pp.91-97
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• 1986

Intra and interspecfic fusants were produced by the protoplast fusion of auxotrophic mutants from Trichoderma koningii ATCC 26113 and Trichoderma reesei QM 9414. It was found that 0.6M $MgSO_4\;and\;0.6M\;NH_4Cl$ was the best osmotic stabilizer for the preparation of protoplasts from the mycelium of T. koningii and T. reesei respectively. However, $MgSO_4$ was the most suitable one for the regeneration of the protoplasts from both species. The intraspecific protoplast fusion frequencies between the auxotrophic mutants from T. reesei were $1.8{\times}10^{-2}\;to\;5.1{\times}10^{-1}$. Interspecific protoplast fusion frequencies between the auxotrophic mutants from T. koningii and T. reesei were $3.6{\times}10^{-3}$\;to\;8.4{\times}10^{-2}. Interspecific complementing fusants, however, were not alwats produced. Fusants obtained from interspecific potoplast fusion were spontaneously segregated into various strains including parental types, non-parental auxotrophic hybrids, and prototrophic hybrids on complete plate. Interspecific hybrids revealed to have partially enhanced celluloytic activities.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.441-444
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• 2004

This paper presnets the tensile behavior of 8 high performance fiber-reinforced cementitious composites (HPFRCCs) members, each reinforced with one deformed bar 16mm in diameter. The variables included HPFRCC(Ductal, steel cord and polyethylene hybrid fiber, PE fiber) versus normal concrete. Fibers used in HPFRCC significantly increased tensile strength, ductility, and tension stiffening of cementitious materials. For HPFRCC, after first cracking, tensile load continue to rise without fracture localization. Sequentially developed parallel cracks contributed to the inelastic strain at increasing stress level. After yielding of the reinforcing bars, HPFRCC showed increases in loads with increasing strains.

• FLOWER RESEARCH JOURNAL
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• v.19 no.1
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• pp.55-63
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• 2011

This study was carried out to develop new cultivars of Hibiscus species from crosses between introduced interspecific hybrids and cultivars in Hibiscus species. Fruit setting of interspecific crosses of Hibiscus strains was less than 10% and the number of seeds in the fruit was also in low level. Three individuals of specific flower and leaf characteristics were selected from crosses between introduced interspecific hybrid, 'Fujimusme'(♀), and H. syriacus 'Namwon'(♂) in 2004. A new strain, Hibiscus ${\times}$ 'W-26', was selected from the crossing of interspecific hybrid, 'Fujimusme'(♀), and H. syriacus 'Namwon'(♂), which had white flower and narrow separated petal. Hibiscus ${\times}$ 'WRB-2' was selected from the crossing of interspecific hybrid, 'Fujimusme'(♀), and H. syriacus 'Namwon'(♂), which had white flower and blue eye spot. Hibiscus ${\times}$ 'R-141' was selected from crosses between introduced interspecific hybrid, 'Shichisai'(♀) and H. syriacus 'Namwon'(♂), which had large flowers over 13 cm diameter and revealed tall tree type. Hibiscus ${\times}$ 'R-142' was selected from the crossing of interspecific hybrid, 'Shichisai'(♀), and H. syriacus 'Namwon'(♂), which had large flowers over 13 cm diameter and revealed tall tree type. The characteristics were succeded after grafting. Flower of 'R-142' had reddish violet color with red eye spot, whereas its parent had blue and purple flowers.

• Journal of Mushroom
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• v.14 no.2
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• pp.64-69
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• 2016

Pleurotus eryngii is one of the most widely cultivated and important edible mushrooms. However, the shelf life of the fruiting body is short, which. To solve this problem, a new cultivar, DanBi 5Ho, of Pleurotus eryngii was developed by mono-mono crossing between monokaryotic strains derived from KNR2598 and KNR2610. The optimum temperature formycelial growth was 25 and that forfruiting body development was 15-16. The quality did not change after a period of 40.0 d at 4. This result was significantly different compared to that ofthe control strain Knneuari 2 Ho. Analysis of genetic characteristics of the new hybrid strain DanBi 5Ho revealeda different profile thanthat of the parental and control strains when random amplification of polymorphic DNA (RAPD) primers we used. The results obtained from this study show that DanBi 5Ho is a new hybrid strain, characterized by improved storability after harvesting.

• Applied Biological Chemistry
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• v.18 no.4
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• pp.219-227
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• 1975

In order to investigate the possibility of wine-making with the grape variety cultivating in Korea, the basic analysises were carried out; analysis of the grape maturity during ripening period, the composition of grape juice, and the chemical components of wine from different varieties. Also the yeasts existing naturally on the grape were isolated and identified. For the selection of strain, the characteristics of 6 strains were studied. The results obtained were summarized as follows. 1. The reducing sugar content increased considerably during two weeks after the ordinary grape-gathering period. 2. The sugar content was highest in Muscat bailey A, which could be fermented naturally. The other varieties, Campbell Early, Steuben, and Alden needed chaptalisation for wine-making. 3. The permanaganate number and the methanol content of wine from all varieties were lower than french wine. 4. The sensory evaluation of wine showed that the pink wine was appreciated better than the red wine of same variety and the foxy taste of wine from hybrid grape influenced little to Korean. 5. The selected 6 strains were identified as Saccharomyces chevaliers, Saccharomyces capensis and Saccharomyces globosus. The strain No. 3 and No. 4 showed the most excellent characters for wine-making.

• Korean Journal of Microbiology
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• v.33 no.1
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• pp.31-37
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• 1997

Intergeneric hybrids between Aspergillus niger and Perricillium ch~y.sop~um(Tyr ), hyperlipolytic enzyne-producing fungi, were obtained by nuclear transfer technique:. Optimal conditions for formation of intergeneric hybrids were investigated. Maximum production of protoplasts were obtainrd by 1% Novozym 234 at $30^{\circ}C$ for 3 hrs and the most effective osmotic stabilizers for the isolation of protoplasts were 0.6 M KC]. Frequencies of hybrid formation by nuclear transfer were $1.3{\times}$10^{-3}$$ $-3.8{\times}$10^{-3}$$. From the chervation of genetic stability, conidial size, DNA content, ;md nuclear stain, it was suggested that their karyotypes are aneuploid. The hybrids showed 1.4-2.2 fold higher lipase activities than parental strains. It was strongly supported by results of this study that nuclear transfer technique is much more efficient in the formation of intergeneric hybrids than protoplast fusion and is very useful for the improvement of strains.

• International Journal of Oral Biology
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• v.35 no.1
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• pp.13-19
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• 2010

The DNA probes Pn17 and Pn34 were evaluated for their ability to specifically detect clinical strains of P. intermedia and P. nigrescens from a Korean population by dot blot hybridization. These probes were sequenced by extension termination and their specificity was determined by Southern blot analysis. The results revealed that the Pn17 sequence (2,517 bp) partially encodes an RNA polymerase beta subunit (rpoB) and that Pn34 (1,918 bp) partially encodes both rpoB (1-169 nts) and the RNA polymerase beta subunit (rpoB'; 695-1918 nts). These probes hybridized with both HindIII- and PstI-digested genomic DNAs from the strains of P. intermedia and P. nigrescens used in this study. Interestingly, each of the hybrid bands generated from the HindIII-digested genomic DNAs of the two bacterial species could be used to distinguish between them via restriction fragment length polymorphism. These results thus indicate that Pn17 and Pn34 can simultaneously detect P. intermedia and P. nigrescens.

• Microbiology and Biotechnology Letters
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• v.24 no.1
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• pp.50-58
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• 1996

Interspecific hybrids between Aspergillus oryzae var oryzae and A. nidulans 514 were obtained by nuclear transfer technique. Several autotrophic mutants isolated from conidiospores of the two strains were mutagenized with ultraviolet and N-methyl-N-nitrosoguanidine. Optimal conditions for formation of intergeneric hybrids were investigated. Frequencies of hybrid formation by nuclear transfer were $3{\times}10^{-5}{\sim}1{\times}10^{-5}$. From observation of genetic stability, conidial size, DNA content, and nuclear stain, it was suggested that their karyptypes are aneuploid. The hybrids showed 1.1~1.4 fold higher xylanase activities than parental strains did. The xylanase of Aspergiilus sp. TAVD514-3 was purified and some of it's enzymatc characteristics were investigated. The enzyme was purified about 85 fold with an overall yield of 17% from the culture medium by ammonium sulfate fractionation, Sephadex G-75 gel permeation chromatography, and CM-sephadex A-50 ion exchange chromatography. The purified enzyme functions optimally at pH 9.0 and 80$^{\circ}C$. The enzymatic activity was increased by the presence of $Mg^{2+}$ and $Mn^2$ ions.

• Korean Journal of Microbiology
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• v.37 no.4
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• pp.312-316
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• 2001

To improve the ethanol fermentability, four Saccharomyces yeast strains with efficient ethanol fermentability were subjected to rare-mating and protoplast fusion. Using these 4 strains, 5 different combinations of mating-pair or fusion-pair were constructed and their hybrids or fusants were obtained. From the statistical analysis of the results of the ethanol fermentation by the hybrids of the different mating-pair or fusion-pair, no difference was found in ethanol production, but [S. kluveri $khl{\times}S$ cerevisiae cp3] pair was shown to be the best combination which can produce high cell-viability. In fact, the clone No. 3 of the [S. kluveri $khl{\times}S$ cerevisiae cp3] pair was selected as the best strain which produced ethanol of 10.11% (w/v) or 12.81% (v/v) from 25% (w/v) glucose at $33^{\circ}C$ for 3 days with the residual sugar of 3.53% (w/v), viability of 62.65%, fermentation efficiency of 92.2%.