• KSBB Journal
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• 제27권3호
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• pp.161-166
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• 2012

The purpose of this work was to examine the antibacterial activity derived from a lactic acid bacterium isolated from korean rice wine, called makgeolli. Various physiological and biochemical properties of this strain were characterized. Both the BIOLOG system and phylogenetic analysis using 16S rRNA sequencing were utilized for identification, and the strain was designated as Lactobacillus casei HK-9, and registered in GenBank as [JQ951606]. Growth rate, production of organic acids (e.g., lactic acid and acetic acid), and pH changes during growth were monitored. The maximum concentrations of lactic acid and acetic acid were approximately 576 mM and 199 mM, respectively, and pH was changed from 7.00 to 3.74 after 72 h of incubation. HPLC was used to confirm the production of lactic acid and acetic acid. Significant antimicrobial activity of the concentrated supernatant was demonstrated against various food-poison causing bacteria (e.g., Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, Escherichia coli, Salmonella enteritidis). Ethanol tolerance of L. casei HK-9 showed up to 12% of ethanol within the culture.

• Journal of Microbiology and Biotechnology
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• 제11권1호
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• pp.112-117
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• 2001

A nonconventional yeast strain Y103 capable of degrading several aromatic hydrocarbons was isolated from the wastewater of the Yocheon industrial complex. The strain Y103 was identified as Yarrowia lipolytica on the basis of its unique dimorphic and biochemical characteristics as determined by a Biolog test. Y. lipolytica Y103 was found to degrade phenol and 4-chlorophenol to produce catechol. The catechol then will be further degraded to produce 2-hydroxymuconic semialdehyde via meta-cleavage. These results indicate that strain Y103 degrades 4-chlorophenol, phenol, and catechol through a consecutive reaction to produce 2-hydroxymuconic semialdehyde. The most active degradation of phenol by Y. lipolytica Y103 occurred with a 0.5 mM phenl concentration in an MM2 medium at $30^{\circ}C$ and pH 7.0.

• KSBB Journal
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• 제32권3호
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• pp.179-186
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• 2017

This study was undertaken to identify and characterize hemolytic Bacillus cereus isolated from commercial ssam-jang. The physiological and biochemical properties of isolate were first examined. Using the BIOLOG system, the isolate was identified and assigned to B. cereus MH-2. Phylogenetic tree of MH-2 was plotted based on 16S rRNA sequence comparisons. Hemolytic activity was observed around wells of sheep blood agar plates seeded with MH-2 cultures; the zone of hemolysis gradually increased with increasing incubation time of the cultures. Zymographic analysis estimated the molecular weight of the presumed hemolysis-causing molecule to be about 30 kDa. Survival rates of MH-2 cells decreased with increasing NaCl concentrations in the media. The stress shock proteins (e.g., DnaK and GroEL) induced by NaCl were reduced in proportion to the NaCl concentration and exposure period to B. cereus MH-2. Analysis of SDS-PAGE and Western blot revealed that the stress shock proteins, 70-kDa DnaK and 60-kDa GroEL were decreased proportionate to the NaCl concentrations as well as exposure period in exponentially growing cultures. Scanning electron microscopy demonstrated the presence of perforations and irregular rod forms with wrinkled surfaces in cells treated with NaCl.

• Journal of Microbiology and Biotechnology
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• 제15권2호
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• pp.362-367
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• 2005

On the basis of high osmotic tolerance and xylitol production, a novel yeast strain was screened from soils of rice farming. The isolated strain HY200 was systematically characterized by using general approaches of Biolog Microlog$^{TM}$ and 18S rRNA sequence analyses, and consequently was designated as Candida tropicalis HY200. Under formulated culture conditions, relatively high xylitol yield ($77\%$) and productivity (2.57 g/l$\codt$h) were obtained, in practice, when 200 g/l of xylose was supplemented. In the utilization of nitrogen, inorganic compounds could not serve as nitrogen sources. As a promising phenotype, HY200 steadily flocculated during and/or after growing in the formulated medium. The extent of flocculation was partly affected by nitrogen sources. However, regardless of the kinds of carbon source fed, the flocculent cells were always observed at the end of the exponential growth phase. These observations strongly suggest that the strain HY200 could effectively be used as a potential candidate for the production of xylitol from xylose, especially in repeated batch mode, because of its flocculation ability and tolerance to high substrate concentrations.

• 복식문화연구
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• 제10권5호
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• pp.578-589
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• 2002

The purpose of this research was to analyze the residual water retention and to determine the number and species of microorganisms from the wet cotton fabrics in dehydration and drying process during washing. The drying rates of terrycloth and interlock knit under the rainy seasons were measured according to the dehydration and hanging methods, layers of fabric and pre-treatment agents. Microorganisms were isolated from the dried terrycloth by pure culture, and were identified by Biolog system. The results are as follow: The initial water retention of fabrics after dehydration decreased in the order of dripping>centrifuge>squeezing method, which affected the drying rate. The drying rates were faster by increasing surface area of fabrics. There was no significant difference in drying rate among the fabrics pre-treated with detergent, or fabric softener, or cationic surfactants such as Cetyltrimethylammonium bromide(CTAB) and Benzalkonium chloride(BC). Puedomonas aureginosa was found in the fabrics treated with a powder-type detergent. On the other side, there was no growth of microorganism in the fabrics treated with a liquid-type detergent (containing antibacterial agent), CTAB and BC.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.126-126
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• 2003

Incidence of crown gall on lower stem of chrysanthemum, Chrysanthemum morifolium Ramat., was first observed at Hwasung, Gyeonggi, Korea in 2001, Tumors on the stem were 1.5-2 cm in size and semi-round with rough surface texture of dark brown color. Four strains of bacteria isolated from the tumor tissues were characterized. Their colonies were convex, glistening, circular with an entire edge, and white to tannish-cream in color on PDA plus CaCO$_3$. They were gram negative, oxidase positive, and growing on DIM agar. The bacterial isolates inducing gall formation in chrysanthemum were identified as Agrobacterium tumefaciens based on biochemical and physiological characteristics, fatty acid profile using Sherlock Microbial Identification System, and substrate utilization patterns using Biolog Identification System. Young chrysanthemum plants inoculated with the bacteria developed typical galls within two to three weeks. Seedlings of tomato and slices of carrot roots also produced typical galls two to three weeks after inoculation. This is the first report on crown gall of chrysanthemum in Korea.

• Advances in environmental research
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• 제3권4호
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• pp.283-292
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• 2014

Iron precipitating organisms play a significant role in the formation of ferric hydroxide precipitate, which acts as strong adsorbent for toxic metal. In this respect four different iron precipitating cultures were isolated from Hutti gold mine surface winze water sample on citrate agar medium. The best isolate was screened out for metal removal study on the basis of fast visual iron precipitation. The selected isolate was identified as Enterobacter sp. based on routine biochemical tests and Biolog GN microplate results and as Enterobacter cloacae subsp. dissolvens by 16S rRNA gene sequence analysis (GenBank accession number EU429448). Influence of medium composition, medium initial pH, the influence of inoculum size, effect of various media and ferric ammonium citrate concentration were studied on metal removal in shake flask experiments. Under the optimized conditions studied, E. cloacae showed $94{\pm}2$, $95{\pm}2$ and $70{\pm}2%$ of cadmium, copper and mercury removal from a simulated waste in shake flask studies. In lab scale column reactor more than 85% of copper and mercury removal was achieved.

• 대한의생명과학회지
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• 제9권2호
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• pp.105-110
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• 2003

Ankyrins are a ubiquitously expressed family of intracellular adaptor proteins involved in targeting diverse proteins to specialized membrane domains in both the plasma membrane and the endoplasmic reticulum. Canonical ankyrins are 190-220 kDa proteins expressed in most tissues and cell types and comprise a membrane-binding domain (MBD) of 24 ANK repeats, a spectrin-binding domain, a death domain and a C-terminal domain. Rescue studies with ankyrin-B/G chimeras have identified the C-terminal domain of ankyrin-B as the defining domain in specifying ankyrin-B activity, but the function of C-terminal domain of ankyrin-B is, however, not known. We report here that the C-terminal domain of ankyrin-B is capable of interacting with the C-terminal Region of Hsp40. The Hsps are induced not only by heat shock but also by various other environmental stresses. Hsps are also expressed constitutively at normal growth temperatures and have basic and indispensable functions in the life cycle of proteins as molecular chaperones, as well as playing a role in protecting cells from the deleterious stresses. The binding sites required in the interaction between C-terminal domain of ankyrin-B and C-terminal region of Hsp40 were characterized using the yeast two-hybrid system and GST-pull down assay. The interaction between ankyrin-B and Hsp40 represents the first direct evidence of ankyrin's role as chaperones.

• 대한수의학회지
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• 제50권3호
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• pp.231-237
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• 2010

This study was conducted to investigate characteristics and antimicrobial susceptibility of Escherichia (E.) coli isolates isolated from vaginal mucosa and clitorial fossa of 105 Thoroughbred mares suspicious of the genital disease in Korea during the period from March 2006 to July 2007. Ninety six E. coli isolates were identified as standard biochemical properties and using BIOLOG system. Fifty three isolates (55.2%) could be classified into a total of 21 O serotypes and forty three isolates (44.8%) were non-typeable with 51 O antisera used in this study. The verotoxin 1 (VT 1) and verotoxin 2 genes were analyzed by multiplex PCR. Among them, one isolate was detected VT 1 gene (130 bp). Most of isolates showed a high susceptibility in ciprofloxacin (100%), enrofloxacin (100%), norfloxacin (100%), cefoxitin (96.9%), gentamicin (96.9%), sulphamethoxazole (96.9%), nitrofurantoin (94.8%), amikacin (93.8%), nalidixic acid (92.7%) and tetracycline (90.6%). These results may provide the basic information to establish strategies for the treatment and prevention of reproductive disease in Thoroughbred mares in Korea.

• 환경생물
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• 제19권1호
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• pp.87-92
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• 2001

For the biological treatment of industrial wastewater containing high concentration of phenol, isolation and characterization of phenol - degrading bacterium were carried out. A bacterial strain P2 capable of degrading phenol was isolated from contaminated soils by enrichment culture technique and identified as the genus Rhodococcus by morphological, cultural, biochemical characteristics, and Biolog system. The optimal medium composition and cultural conditions for the growth and degradation of phenol by Rhodococcus sp. P2 were 0.1% of (NH$_4$)$_2$SO$_4$, 0.2% of KH$_2$PO$_4$, 0.25% of Na$_2$HPO$_4$ㆍ12$H_2O$, 0.2% of MgSO$_4$ㆍ7$H_2O$, and 0.008% of CaC1$_2$ㆍ2$H_2O$ along with initial pH 8.5 at 3$0^{\circ}C$. Rhodococcus sp. P2 could grow with phenol as the sole carbon source up to 1,800 ppm in batch cultures, but did not grow in medium containing above 2,000 ppm of phenol. When 800 ppm phenol was given in the optimal media, Rhodococcus sp. P2 completely degraded it within 24 h. Meanwhile, 1,800 ppm of phenol was degraded within 9 days. Rhodococcus sp. P2 could utilize toluene, n-hexane, xylene and benzene as sole carbon source .