• Applied Biological Chemistry
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• v.46 no.3
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• pp.176-182
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• 2003

An alkaline fibrinolytic protease-producing bacteria was isolated front Korean traditional soy sauce and identified as Bacillus subtilis K7 from the results of analyses of its morphological and physiological properties, $API^{\circledR}$, and Biolog system. The enzyme was purified by 75% ammonium sulfate fractionation, QAE-Sephadex anion and SP-Sephadex cation exchange column chromatography and Sephadex G-100 gel filtration. The specific activity of the purified enByme was 233.9 unit/mg protein and the yield of enzyme was 3.8%. The homogeneity of the purified enzyme was confirmed by polyacrylamide gel electrophoresis. Molecular mass of the enzyme was estimated about 21,500 Da by SDS-polyacrylamide get electrophoresis and gel chromatography. The optimum temperature and pH for the enzyme activity were $40^{\circ}C$ and 9.0, respectively. The enzyme was stable in a pH range of 5.0 to 12.0, and 60% of its activity was lost on heat treatment at $50^{\circ}C$ for 20 min. The activity of the purified enzyme was inhibited by the presence of $Fe^{2+},\;Ag^{2+},\;Cu6{2+}$, iodoacetate, ethylene diamine tetraacetic acid (EDTA), and trans-1,2-diaminocycloheane-N,N,N',N'-tetraacetic acid (CDTA). The results indicates that the enzyme requires a metal ion for its enzymatic activity.

• Korean Journal of Environmental Agriculture
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• v.35 no.4
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• pp.294-301
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• 2016

BACKGROUND: Recent studies have described the importance of microbes and enzymes that can compost food waste. This study was carried out to improve production of protease of isolated microbes from food waste. METHODS AND RESULTS: Seven bacteria isolated from various sources were screened for protease production by adding skim milk into the agar medium. About 7 microbes producing protease were tested, and strain JH-35 showed the highest protease activity among them. The strain was identified as Bacillus amyloliquefaciens JH-35 based on morphological, cultural, physiological characteristics and 16S rRNA. In the fermentation experiment, the assay B. amyloliquefaciens JH-35 showed the highest protease activity in the condition of 1% glucose, 1.5% yeast extract and 0.2%$ K_2HPO_4$. The optimal condition of culture with temperature $35^{\circ}C$, initial pH of 7 and shaking speed of 200 rpm and 24 hr. CONCLUSION: The protease of the B. amyloliquefaciens JH-35 had its activity at pH 7 and the optimal culture time was 24 hr. Also, B. amyloliquefaciens JH-35 was high salt tolerance. Our results suggest that B. amyloliquefaciens JH-35 from food waste may have the potential to degrade protein and carbohydrate in food waste.

• Research in Plant Disease
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• v.11 no.2
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• pp.162-166
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• 2005

Disease progress of gray blight of tea (Camellia sinensis O. Kuntze) cv. Yabukita was investigated during the growing season of 2004 at Boseong Tea Experiment Station, Jeonnam Agriculture Research and Extension Service, Boseong, Jeonnam. The disease began to occur from late June and peaked in late July. Antagonistic bacteria against Pestalotiopsis longiseta, the causal pathogen of causing gray blight of tea plants were isolated from phylloplanes of tea plants. An isolate BD0310 which showed the strongest antifungal activity against the pathogen but nonpathogenic to tea plants was selected as a biocontrol agent for the gray blight. The isolate was identified as Bacillus subtilis based on its cultural, morphological, and biochemical characterization and 16S rDNA sequence analysis.

• Research in Plant Disease
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• v.16 no.2
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• pp.158-162
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• 2010

Four promising biocontrol agents against Phytophthora capsici were selected from 507 bacterial isolates collected from rhizosphere soils and roots of pepper plants. In vitro experiment, these four biocontrol agents inhibited mycelial growth, germination of cystospores, and formation of zoosporangia and zoospores of Phytophthora capsici. In the pot experiment, the four biocontrol agents showed control efficiency higher than 70%. In greenhouse experiment, the isolates G28-6 gave the control value of 79.4%. These four biocontrol agents successfully colonized in the population density beyond 105 cfu/g on roots of pepper in vitro. The isolates G28-6 was identified as Pseudomonas aurantiaca, based on its cultural, morphological, and biochemical characterization and 16S rRNA gene sequence analysis.

• Journal of Sericultural and Entomological Science
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• v.36 no.1
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• pp.30-36
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• 1994

choChorion(egg-shell) morphology of the F1 hybrid between Bombyx mori and Bombyx mandarina has been observed by scanning electrom microscope and chorion protein was analyzed by electrophoresis. The chorion surface structure of F1 hybrids in the lateral(flat) region was similar to that of maternal line. The F1 hybrids chorion was found to have basically a three layer structure. The middle and inner layer were very much like those of the Bombyx mandarina and Bombyx mori. There were many conic pillar structures in the outer layer of the F1 hybrid, which was similar to Bombyx mandarina. This conic pillar structure had a thin cover layer was more clear in the dorsal and ventral side of the F1 hybrid chorion. The conic pillar structure of Bombyx mandarina was found to be dominant in F1 hybrid chorion irrespective of their maternal line. Major components of chorion protein were analyzed by two-dimensional electrophoresis and found to have isoelectric points in the range of pH 4.0-6.5 and molecular weight 10 to 50 kd. F1 hybrid chorion protein components related directly to those of the maternal line. The conic pillar structure was dominat characteristic and it was present in all F1 hybrid.

• The Korean Journal of Mycology
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• v.25 no.3 s.82
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• pp.191-201
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• 1997

A mutant (HSMl) of Cryphonectria parasitica created during transformation reproduced the hypovirulent symptoms in virus-free wild type. Its phenomena have been proved with morphological marker such as reduced sporulation, pigmentation, and laccase production. In addition to the changes in phenotypic characteristics, down-regulations of Lac1, Crp1, Vir1 and Vir2 were also observed. The integration of transforming vector was confirmed and located within genome by marker rescuing. Vector integration occurred between two genes, Cpg2 and Cpg3, which resulted in the disruption of neither Cpg2 nor Cpg3. Both Cpg2 and Cpg3 genes, sized at 1.8 kb and 1.9 kb respectively, were rarely transcribed genes in Cryphonectria parasitica. Cpg2 expression was significantly overexpressed from 4 to 5 day old culture of both UEP1 and HSM1 while no differences were observed in Cpg3 expression. It appears that an aberration from the normal expression of Cpg2, not Cpg3, results in the hypovirulent symptoms in virus-free wild type.

• Korean Journal of Environmental Biology
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• v.38 no.3
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• pp.433-449
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• 2020

Nine fish and one clam species were collected from freshwater environments in Korea, including four lakes, two streams, and the Nakdong River, to investigate the host-associated bacteria. Hundreds of bacterial strains were isolated from the samples using a cell sorter and a dilution plating method. After identification of the bacterial strains using 16S rRNA gene sequences, 42 strains with greater than 98.7% sequence similarity with validly published species were determined to be unrecorded bacterial species in Korea. These strains were phylogenetically diverse and assigned to four phyla, six classes, 17 orders, 27 families, and 32 genera. At the genus level, the unrecorded species were classified as Corynebacterium, Mycobacterium, Mycolicibacterium, Gordonia, Williamsia, Modestobacter, Brachybacterium, Sanquibacter, Arthrobacter, and Mycolicibacterium of the class Actinobacteria; Empedobacter, and Flavobacterium of the class Flavobacteriia; Fictibacillus, Psychrobacillus, Cohnella, Paenibacillus, Rummeliibacillus, Enterococcus, and Vagococcus of the class Bacilli; Aquamicrobium, Paracoccus, and Sphingomonas of the class Alphaproteobacteria; Achromobacter, Delftia, and Deefgea of the class Betaproteobacteria; and Aeromonas, Providencia, Yersinia, Marinomonas, Acinetobacter, and Pseudomonas of the class Gammaproteobacteria. The 42 unrecorded species were subjected to further taxonomic characterization using gram staining, cellular and colony morphological determination, biochemical analyses, and phylogenetic analyses. This paper provides detailed descriptions of the 42 previously unrecorded bacterial species.

• Journal of fish pathology
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• v.3 no.1
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• pp.1-9
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• 1990

The present study was carried out to reveal the characteristics of organism responsible for so called vibriosis prevailing in warm water season among cultured kuruma prawn Penaeus japonicus. A bacterium was isolated from the heart, lymphoid organ and muscle of the diseased kuruma prawn. Six strains obtained from diseased kuruma prawn in some culture farms in Namhae and Anhung from august to october in 1989 were submitted to the morphological, biochemical and physiological characterization. All the strains were gram-negative, nonsporning short rods with one polar flagellum. Glucose was fermented with no gas production by these strains. Some distinguishing features of the organisms were negative to lysine, arginine, ornithine decarboxilization test. In general, the temperature $20{\sim}27^{\circ}C$, the NaCl concentration of 2~3% and pH of 6~8 were optimal for the growth in peptone water. The organisms were sensitive to the vibrio static agent 0/129. The isolated should be identified as Vibrio sp.. No essential differences in histopathological finding were noted between the naturally and the experimentally infected prawns. Most characteristic pathological changes were extensive necrosis caused by severe bacteria invasion and multiple formation of meranized nodules in the lymphoid organ.

• Journal of Life Science
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• v.11 no.5
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• pp.432-438
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• 2001

Various lactic acid bacteria were isolated from Korean Dongchimi (whole radish Kimichi with added water) in order to study their antimutagenic activity. Ames test using Salmonella enterica serovar typhimurium TA98 and TA100 showed the strain DLAB19 to have the highest antimutagenic activity among the 300 isolated strains against MNNG(N-methyl-N-nitro-N-nitrosoguanidine), NPD (4-nitro-O-phenylenediamine), 4-NQO(4-nitroquinoline-1-oxide) and AFB$_{1}$(aflatoxin B$_{1}$). The strain was identified as Leuconostoc mesenteroides subsp. cremoris according to the Bergeys Mannual Systematic Bscteriology based on its morphological, cultural, physiological characteristics and biological system Antimutagenic activity of Leu. mesenteroides subsp. cremoris DLAB19 was found in the culture supernatant suggesting the bacterium secretes, the antimutagenic substance in the media. The antimutagenic activity of Leu. mesenteroides subsp. cremoris DLAB19 was reconfirmed by the spore-rec assay using spores of Bacillus subtilis H17 (Rec$^{+}$) and M45 (Rec$^{[-10]}$ ).).

• KSBB Journal
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• v.20 no.5 s.94
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• pp.345-349
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• 2005

The microorganism for odor gas removal was isolated from sewage and contaminated soil. This was characterized as Pseudomonas sp. TKC by morphological, biochemical/physiological, and cultural characteristics analysis of the isolates. The optimum conditions for isolates growth were as follows; substrate concentration 500 ppm, initial medium pH 7.0, incubation temperature $30^{\circ}C$, agitation speed 150 rpm, and MSM medium containing 3 g/L $(NH_4)_2SO_4$.