• Journal of Microbiology and Biotechnology
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• v.11 no.4
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• pp.685-692
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• 2001

A gene, Egl, from Paenibacillus sp. KCTC 8848P encoding endo-${\circ}$-1,4-glucanase was cloned and expressed in Escherichia coli. It consisted of an open reading frame of 1,191 bp for a protein that consisted of 397 amino acids with a molecular weight of 44,539 Da. The deduced amino acid sequence of the endo-${\circ}$-1,4-glucanase gene had a 94% similarity to the endo-$\beta$-1,4-glucanase of Bacillus polymyxa. The Egl gene was also expressed in Saccharomyces cerevisiae secreting Endomyces fibuliger $\beta$-glucosidase (BGL1) under the control of the alcohol dehydrogenase (ADC1) gene promoter, S. cerevisiae transformant producing both endo-${\circ}$-1,4-glucanase and ${\circ}$-glucosidase grew on carboxymethyl cellulose as the sole carbon source.

• The Korean Journal of Pesticide Science
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• v.19 no.1
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• pp.71-79
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• 2015

In order to investigating the effects of antifungal activity of intestinal bacteria obtained from insect, it was identified these bacteria isolated from the gut. In this result, total 49 isolates of intestinal bacteria were identified from 10 kinds of insect species. It was that 4 isolates including Cedecea sp. from Nesidiocoris tenuis, 3 isolates including Enterobacter sp. from Odontotaenius disjunctus, 4 isolates including Acinetobacter sp. from Reticulitermes speratus, 4 isolates including Clavibacter sp. from Riptortus clavatus, 11 isolates including Bacillus sp. from Lema decempunctata, 3 isolates including Enterococcus sp. from Henosepilachna vigintioctopunctata 2 isolates including Staphylococccus sp. from Harmonia axyridis, 5 isolates including Enterobacter asburiae from Popillia mutans, 7 isolates including Aeromonas sp. from Hydrophilus acuminatus, and 7 isolates including Brucella sp. from Anomala octiescostata. In order to investigating antifungal activity against plant-pathogenic fungi, Altanaria solani, Colletotrichum gloeosporioides, Botrytis cinerea, Fusarium oxysporum, Phytophthora capsici, Rhizoctonia solani and Selerotinia sclerotiorum were dual cultured with each 49 gut enterobacteriaceae. As these results showed that many isolates have the antifungal activities including 26 isolates against A. solani, 6 isolates against B. cinerea, 13 isolates against C. gloeosporioides, 11 isolates against F. oxysporum, 17 isolates P. capsici, 2 isolates against R. solani and 2 isolates against S. sclerotiorum. Pseudomonas aeruginosa was showed strong antifungal activity against all of tested plant pathogens. It might be taken a potential for application against plant-pathogenic fungi with useful control agent.

• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.76-81
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• 2008

Currently, natural food colorants and preservatives are being used for their general health benefits. Monascus koji, the product of certain fungi that grow on rice grains, has been added to many foods for coloring and preservation. In this study, the antimicrobial activities of Monascus koji ethanol extracts were investigated. Six Monascus strains (M. araneosus KFRI 00371, M. kaoliang ATCC 46597, M. pilosus IFO 4520, M. purpureus IFO 4482, M. ruber IFO 32318 and M. sp. ATCC 16437) were selected based on their relative intensity of red pigment. Two Monascus extracts, M. kaoliang ATCC 46597 and M. purpureus IFO 4482, displayed antimicrobial activities against Bacillus subtilis, B. cereus, Micrococcus luteus, Staphylococcus aureus and Salmonella typhimurium in concentration-dependent manners. The two extracts showed their strongest antimicrobial activity against S. typhimurium, a cause of food poisoning. Therefore, these results suggest that Monascus koji could be used as a natural food colorant and preservative.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.1
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• pp.76-83
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• 1999

Studies were conducted during 2 months from May of 1997 to evaluate the effects of pig manure compost(PMC) on soil microbial flora. To do so, a field experiment of Chinese cabbage(Brassica campestris L.) was conducted in a randomized block design on a sandy loam soil and microbial floral characteristics in soils were analyzed. Treatments to control included the application of PMC at (A) $8Mg\;ha^{-1}$CM-8), (B) $29Mg\;ha^{-1}$(CM-2,9), and (C) $57Mg\;ha^{-1}$(CM-57), and of chemical fertilizer(D) at $320N-80P_2O_5-200K_2O\;kg\;ha^{-1}$(NPK). In each treatment, the rhizosphere and non-rhizosphere soils were tested for the analysis of microbial populations. The populations of bacteria, actinomycetes, and fungi increased in soils with the applications of PMC and chemical fertilizer, but that of Bacillus sp. decreased. However, the population of fluorescent Pseudomonas sp. was reduced in NPK plots only. With increasing application rates of PMC, the number of colony forming units(cfu) of bacteria (Pseudomonas sp. and actinomycetes) and fungi increased. in all PMC-treated plots, the population density peaked at early growth stage for bacteria(including Bacillus sp.), at late growth for fluorscent Pseudomonas sp., and at harvest for fungi and actinomycetes. The rhizosphere effect was greatest for fluorscent Pseudomonas sp. As the application rates of PMC increased, Total N, organic matter, available phosphate, and exchangeable -K, -Ca, and -Mg increased compared to control, but soil pH was lowered. In NPK plots, EC was 3.4-fold and exchangeable K was 5-fold higher than control.

• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.563-567
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• 1989

An alkalophilic bacterium isolated from compost was selected, identified and tested for the production of glutamic acid from ammonium fumarate. The bacterium was closely related to Bacillus brevis. The conditions for glutamic acid production were pH 8.0, 2% fumaric acid, and 0.8% nutrient broth. The mechanism of glutamic acid formation in this strain was postulated as following scheme. (1) Ammonium fumarate longrightarrow Aspartic acid (2) Aspartic acid ＋ $\alpha$-Ketoglutaric acid longrightarrow Glutamic acid + Oxaloacetic acid.

• Microbiology and Biotechnology Letters
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• v.32 no.1
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• pp.96-100
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• 2004

Chlorothalonil is a wide-spectrum fungicide that is widely used in the world. Chlorothalonil is known as a potential toxic pollutant due to its high application rate, persistence, and toxicity to humans and other species. With the Increase of necessity of bioremediation, this study was conducted to isolate the chlorothalonil dissipation bacteria from soil. Soil samples were collected from 184 sites of farmland and wastewater disposal soil.661 strains resistant to chlorothalonil were isolated by dilution method from chlorothalonil-containing enrichment culture. After incubating at $30^{\circ}C$ in 1/10 LB media containing 10 ppm of chlorothalonil for a week, dissipation ability of chlorothalonil was investigated by HPLC. Finally, a strain SH35B, capable of dissipating chlorothalonil efficiently, was selected. The strain SH35B was identified as Ochrobactrum sp. Ten ppm of chlorothalonil In 1/10 LB media were completely dissipated by the growth of Ochrobactrum sp. SH35B for 30 h at $30^{\circ}C$. In the isolated strain, the content of glutathione and the activity of glutathione S-transferase were supposed to be ones of the Important factors for chlorothalonil dissipation and were higher than those of control strains, Escherichia coli and Bacillus subtilis.

• Food Science and Biotechnology
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• v.15 no.4
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• pp.549-554
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• 2006

To standardize a manufacturing method and improve the quality of traditional kochujang, eight-types of meju with different shapes (brick, grain) were prepared using Aspergillus oryzae (A.o) or Aspergillus sojae (A.s) alone or in combination with Bacillus subtilis (B.s). The physicochemical characteristics and enzyme activities of the various meju were compared during fermentation for 12 days at $28^{\circ}C$. The moisture content of both the brick- and grain-shaped meju were gradually decreased from an initial content of 50.47 to 54.89% to a content of 12.91 to 16.25% on day 12 of fermentation. The neutral protease activities of the brick-shaped meju ranged from $1.19{\pm}0.12$ to $1.25{\pm}0.28\;unit/mL$, and were similar for all treatments. The ${\alpha}$-amylase activities in A.s+B.s treatment of brick-shaped and grain-shaped meju were the highest, $11{\pm}0.6$ and $9{\pm}0.7\;unit/mL$, respectively. The ${\beta}$-amylase activities ranged from $1.53{\pm}0.01$ to $1.56{\pm}0.02\;unit/mL$, and were similar for all treatments. The amino type nitrogen content of A.o+B.s brick-shaped meju was the highest, $0.39{\pm}0.03%$. We confirmed that the brick-shaped meju prepared with A. oryzae and B. subtilis could be used to prepare traditional kochujang to improve the quality of the product.

• Journal of Microbiology and Biotechnology
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• v.12 no.2
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• pp.340-344
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• 2002

A gene, npl, encoding neopullulanase from Paenibacillus sp. KCTC 8848P was cloned and expressed in Escherichia coli. It consisted of an open reading frame of 1,530 bp for a protein that consisted of 510 amino acids with a molecular weight of 58,075 Da. The deduced amino acid sequence of the neopullulanase gene had $92\%$ identity with the neopullulanase of Bacillus polymyxa. The npl gene was also expressed in Saccharomyces cerevisiae secreting Schwanniomyces occidentalis glucoamylase (GAM1) under the control of the yeast actin gene (ACT1) promoter. Secretion of the neopullulanase was directed by the yeast mating pheromone ${\alpha}$ -factor ($MF{\alpha}1$) prepro region. Enzyme assays confirmed that co-expression of npl and GAM1 enhanced starch and pullulan degradation by S. cerevisiae.

• Proceedings of the Microbiological Society of Korea Conference
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• 2003.05a
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• pp.122-124
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• 2003

Cyclodextrin glucanotransferase (CGTase) and endoxylanase genes of Bacillus sp. were subcloned down-stream of yeast ADH1 promoter and expressed in S. cerevisiae. Most of the CGTase and endoxylanase expressed were detected in the extracellular medium with activity of 0.6 and 7-8 unit/ml, respectively. The recombinant enzymes were secreted as N-linked-glycosylated forms, resulting an enhanced thermal stability. CGTase predominantly produced $\alpha-cyclodextrin$ from starch and endoxylanase produced xylobiose and xylotriose from xylan.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.106-107
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• 2003

The effect of biological control agent Bacillus sp. (BAC03-3-1, BAC03-3-2, BAC02-4) on pre- and postemergence Sclerotinia rot of perilla (Perilla frutescens var. japonica) caused by Sclerotinia sclerotiorum was determined from greenhouse field trials. The ability of this antagonist to reduce germination of sclerotia of S. sclerotiorum was also evaluated. In the greenhouse, suspension of BAC03-3-1 application as root drench of perilla, which provided as little as 10$\^$7/ cells/ $m\ell$ per gram of soil, significantly increased plant stand in pathogen-infested soil over that in the untreated control. All three isolates reduced the germination of sclerotia of S. sclerotiorum in loamy sand soils in the greenhouse. In loamy sand amended with rice bran the sclerotial germination was inversely correlated (r = -0.79) with perilla stand in the greenhouse. However, a higher rate of bacterial suspension with rice bran(Ig dwt./100g soil) than that applied with bacterial suspensions only was necessary to achieve a comparable reduction in sclerotial germination. In field study, all three isolates added to soil to provide 10$\^$7/ cells/$m\ell$ per gram significantly prevented Sclerotinia rot (73-85％) after 35 days of growth. The isolate BAC02-4, BAC03-3-1 and BAC03-3-2 gave final stands of 65 to 75, 60 to 70, and 55 to 60％, respectively. The addition of rice bran(1 ％) to loamy sand in the field resulted in a 10-fold increase in propagule numbers of the three isolates within 10 days of application.