• Microbiology and Biotechnology Letters
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• v.22 no.6
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• pp.571-576
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• 1994

One strain of cellulose-producing Acetobacter was isolated from the traditionally fermen- ted grape vinegar in Korea. The isolated strain, designated as KI strain was identified as the Acetobacter xylinum with respect to physiological and biochemical characteristics. KI produced acetic acid from ethanol, and then decomposed acetate to CO$_{2}$ and H$_{2}$O. When the isolated strain was cultivated statically in broth culture, a thick cellulose pellicle was formed. KI was tolerance of 8% ethanol and 30% glucose, and the isolate was positive in ketogenesis from glycerol, $\gamma$-pyrone from glucose and fructose, and 2-ketogluconic acid from glucose. KI strain possessed straight-chain C$_{18:1}$, C$_{16:0}$, and C$_{14:0}$ fatty acid, and contained ubiquinone Q$_{9}$ and Q$_{10}$ as isoprenoid quinone. DNA base composition of KI strain was 57.6% G+C.

• Communications of the Korean Mathematical Society
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• v.16 no.2
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• pp.287-290
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• 2001

Let X$_1$, X$_2$, … be a sequence of independent and identically distributed random variables with continuous cumulative distribution function F(x). X(sub)j is an upper record value of this sequence if X(sub)j > max {X$_1$, X$_2$, …, X(sub)j-1}. We define u(n) = min {j│j > u(n-1), X(sub)j > X(sub)u(n-1), n $\geq$ 2} with u(1) = 1. Then F(x) = 1 - e(sup)-x/c, x > 0 if and only if E[X(sub)n(n+1) - X(sub)u(n)│X(sub)u(m) = y] = c or E[X(sub)u(n+2) - X(sub)u(n)│X(sub)u(m) = y] = 2c, n $\geq$ m+1.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.80-83
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• 2007

In order to characterize the catalytically active sites on carbon black, acetylene chemisorption had been examined recently at 773 and 873 K by using a pulse technique. As the inject ion was repeated at 773 K, the adsorbed amount gradually decreased and eventually the adsorption did not occur any more. At 873 K a constant amount of $C_2H_2$ was consumed repeatedly after several injections. Good linear relationships were obtained between the methane decomposition rate at 1123 or 1173 K and the cumulative acetylene adsorption at 773 K or the constant acetylene consumption at 873 K. Reasonable models for the associative acetylene chemisorption at 773 K and the constant acetylene consumption at 873 K on the armchair face at the edges of graphene layers were proposed. The constant consumpt ion may be explained by the "$C_2H_2$-addition-hydrogen- abstract ion (CAHA)" mechanism.

• Bulletin of the Korean Chemical Society
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• v.16 no.10
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• pp.900-903
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• 1995

• Mycobiology
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• v.38 no.3
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• pp.215-218
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• 2010

Azoles are currently the most widely used class of antifungal drugs clinically, and are effective for treating fungal infections. Target site of azoles is ergosterol biosynthesis in fungal cell membrane, which is absent in the mammalian host. However, the development of resistance to azole treatments in the fungal pathogen has become a significant challenge. Here, we report the identification and functional characterization of a UPC2 homolog in the human pathogen Cryptococcus neoformans. UPC2 plays roles in ergosterol biosynthesis, which is also affected by the availability of iron in Saccharomyces cerevisiae and Candida albicans. C. neoformans mutants lacking UPC2 were constructed, and a number of phenotypic characteristics, including antifungal susceptibility and iron utilization, were analyzed. No differences were found between the mutant phenotypes and wild type, suggesting that the role of C. neoformans UPC2 homolog may be different from those in S. cerevisiae and C. albicans, and that the gene may have a yet unknown function.

• Bulletin of the Korean Chemical Society
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• v.18 no.3
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• pp.311-316
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• 1997

The synthesis and characterization of the mononuclear group 13 heterocyclic carboxaldehyde methyldithiocarbazate complexes Me2M[NC5H4CRNNC(S)SCH3] (M=Al, R=H(1); M=Ga, R=H(2); M=Al, R=CH3(3); M-Ga, R=CH3(4); M=In, R=CH3(5)) are described. Compounds 1-5 were prepared by the reaction of MMe3 (M=Al, Ga, In) with 2-formy or 2-acetylpyridine-S-methyldithiocarbazate in toluene. These compounds 1-5 have been characterized by microanalysis, NMR (1H, 13C) spectroscopy, mass spectra, and single-crystal X-ray diffraction. X-ray single-crystal diffraction analyses reveal that 4-5 are mononuclear metal compounds with coordination number of 5 and N,N,S coordination mode.

• The Plant Pathology Journal
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• v.23 no.2
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• pp.37-44
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• 2007

Colletotrichum contains many important pathogens which cause economically significant diseases of crops like pepper, strawberry, tomato and apple. Forty four isolates were collected to characterize the diversity of Colletotrichum causing apple anthracnose in various regions of Korea. They were analyzed by random amplified polymorphic DNA (RAPD), internal transcribed spacer (ITS) of rDNA and partial $\beta$-tubulin gene DNA sequence, and culture characteristics on PDA and PDA-Benomyl. From the results of molecular analyses, 31 strains belonged to Colletotrichum gloeosporioides, ribosomal DNA group (RG) 4 of Moriwaki et al. (2002), 8 strains belonged to C. acutatum, A2 group of Talhinhas et al. (2005) and 5 strains to C. acutatum, A3 group of Talhinhas et al. (2005). Most isolates of C. gloeosporioides RG4 grew faster on PDA than strains of C. acutatum, A2 and A3 groups and most RG4 strains were sensitive to Benomyl. However, a few strains of RG4 grew slower and were resistant to Benomyl. On the basis of molecular characteristics, apple isolates of C. acutatum were clearly differentiated from red pepper isolates of the species, but apple isolates of C. gloeosporioides were not.

• Proceedings of the Materials Research Society of Korea Conference
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• 1997.05a
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• pp.21-21
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• 1997

• Bulletin of the Korean Chemical Society
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• v.20 no.5
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• pp.600-604
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• 1999

• Environmental Mutagens and Carcinogens
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• v.17 no.1
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• pp.1-6
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• 1997

The RAD4 gene of Saccharomyces cerevisiae is essential for the incision step of UV-induced excision repair. A yeast RAD4 gene has been previously isolated by functional complementation. In order to identify the RAD4 homologous gene from fungus Coprinus cinereus, we have constructed cosmid libraries from electrophoretically separated chromosomes of the C. cinereus. The 13 C. cinereus chromosomes were resolved by pulse-field gel electrophoresis, hybridized with S. cerevisiae RAD4 DNA, and then isolated homologous C. cinereus chromosome. The insert DNA of the RAD4 homolog was contained 3.2 kb. Here, we report the partial cloning and characterization of fungus C. cinereus homolog of yeast RAD4 gene. Southern blot analysis confirmed that C. cinereus contains the sequence homologous DNA to RAD4 gene and this gene exists as a single copy in C. cinereus genome. When total RNA isolated from C. cinereus cells was hybridized with the 1.2 kb PvuII DNA fragment of the S. cerevisiae RAD4 gene, a 2.5 kb of transcript was detected. The level of the transcript did not increase upon UV-irradiation, suggesting that the RAD4 homologous gene in C. cinereus is not UV-inducible.