• The Korean Journal of Food And Nutrition
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• v.8 no.3
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• pp.253-261
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• 1995

A strain of alkalophilic Bacillus sp. C-21 has been Isolated from sold. The strain was capable of producing large amount of cyclodextrin glycosyltransferase (CGTase) in the high alkaline pH medium. The preferable medium composition was determined to be as follows : 1.0% soluble starch, 1.0% peptone, 0.5% yeast extract, 0.1% K2HP04, 0.02% MgSO4.7H2O and 1.0% Na2CO3(pH 10.0) The highest enzyme production was observed after 30hours of cultivation at 33$^{\circ}C$. The optimum temperature and pH for the activity of crude enzyme were 6$0^{\circ}C$ and 6.0, respectively. The enzyme was stable between pH 6.0 and 9.6, and up to 55$^{\circ}C$.

• Microbiology and Biotechnology Letters
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• v.23 no.5
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• pp.544-549
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• 1995

The alkaline elastase is an extracellular serine protease of the alkalophilic Bacillus strain Ya-B. To increase the gene copy number and the production level of the alkaline elastase Ya-B, we designed, on the B. subtilis chromosome, a gene amplification of the 10.6 kb repeating unit containing amyE, aleE (alkaline elastase Ya-B gene) and tmrB. The aleE was inserted between amyE and tmrB, and B. subtilis APT119 strain was transformed with this amyE-aleE-tmrB-junction region fragment. As a result, we succeeded in obtaining tunicamycin-resistant (Tm$^{r}$) transformants (Tf-1, Tf-2) in which the designed gene amplification of 10.6 kb occurred in chromosome. The transformants showed high productivity of $\alpha $-amylase and alkaline elastase Ya-B. The copy number of the repeating unit (amyE-aleE-tmrB) was estimated to be 25, but plasmid vector (pUC19) was not integrated. The amplified aleE of chromosome was more stable than that of plasmid in absence of antibiotics.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.2
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• pp.305-312
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• 2011

Bacillus anthracis(Ba) is a Gram-positive spore-forming bacterium that causes the disease anthrax. The feature of Ba is the presence of two large virulence plasmids, pXO1 and pXO2. Molecular genotyping of Ba has been difficult to the lack of polymorphic DNA marker. Ba isolated from Korea has been genotyped using various nucleotide analysis methods, such as 16s rDNA sequencing and multiple-locus variable-number tandem repeat (MLVA) analysis. We identified genotypes that represent a genetic lineage in the B1 cluster. This study emphasized the need to perform molecular genotyping when attempting to verify a strain-specific Ba.

• Microbiology and Biotechnology Letters
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• v.21 no.5
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• pp.478-485
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• 1993

The strain which produced highly viscous exopolysaccharides (EPS) in liquid culture was selected from soil. The strain was supposed to Bacillus sp. from the results of mophological, biochemical and physiological tests. The medium composition for EPS production was trypton 0.75%, sucrose 4%, CaCO3 0.01%, Winogradsky's nitrogen free mineral medium 5ml/l and pH 7.0. In 2-l jar fernenter, the viscosity of culture broth after 120-hr cultivation time was very high (60, 000 cps) and the amount of EPS was 6.2g/l.

• Korean Journal of Organic Agriculture
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• v.11 no.4
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• pp.61-74
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• 2003

This study was conducted to screen the antagonistic bacteria which inhibit the growth of plant pathogen, fusarium wilt(Fusarium oxysporum) occurred in tomato plants in greenhouse. We isolated an effective bacterial strains and investigated into the antifungal activity of the antagonistic microorganism and it’s identification. Ten bacterial strains which strongly inhibited Fusarium oxysporum were isolated from the nature, and the best antagonistic bacterial strain designated as KC175, was selected. The antagonistic strain KC175 was identified to be the genus Bacillus sp. based on the morphological and biochemical characterization. The Bacillus sp. KC175 showed 58.2% of antifungal activity against the growth of Fusarium oxysporum. By the bacterialization of the culture broth and the heat bacterialization culture filtrate of it, Bacillus sp. KC175 showed 91% and 18% of antifungal activity, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.3
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• pp.476-482
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• 2006

The aim of this work was to perform the screening and identification of the bacterium, MK-15 having the activity of fibrinolytic enzyme for the commercial use. Initially, strain MK-15 was enriched and isolated from naturally fermented soybean. Morphological and various physiological characteristics of the strain MK-15 was examined. The activity of fibrinolytic enzyme derived from supernatants of test culture MK-15 was performed by fibrin plate method for solid fibrinolytic activity. As the result, the fibrinolytic activity of MK-15 grown on the soybean media was about 2.7 times greater than that of plasmin used as stardard. 16S rRNA analyses revealed that strain MK-15 was 99.9% similar to Bacillus subtilis species cluster, and the bacterium was designated as Bacillus sp. MK-15. Strain MK-15 was registered in GenBank as [DQ163021].

• Applied Biological Chemistry
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• v.41 no.1
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• pp.18-22
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• 1998

A mutant strain which hyperproduced thermostable ${\alpha}-amylase$ was obtained by chemical mutagenesis of Bacillus licheniformis. The mutant strain, SK-5, produced the enzyme about 50 times higher than the original strain. The mutant was longer and slimmer in shape, slower in growth compared to the original strain. Nucleotide sequence analysis of the SK-5 ${\alpha}-amylase$ gene revealed no changes in the the structural gene. The changes found in the promoter region might be responsible for the hyperproduction of the enzyme by the mutant. No structural changes in the enzyme structure could be observed when the secreted enzymes at various culture times were analyzed by Western blot.

• The Korean Journal of Community Living Science
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• v.18 no.2
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• pp.241-246
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• 2007

This study was conducted to select and screen for an antifungal bacterial strain showing pathogen inhibitory activity against Diaporthe actinidiae, which causes stem-end rot in kiwi fruit. Four bacterial strains were isolated which strongly inhibit Diaporthe actinidiae from among two hundred and fifty bacterial strains screened from the soil where kiwi fruit were grown. By co-culturing bacterial strain #72 and the pathogen causing the stem-end rot of kiwi fruit, bacterial strain #72 showed 81.0% antifungal activity against Diaporthe actinidiae. Bacterial strain #72 was identified to be from the genus Bacillus sp. based on morphological and biochemical characterization. The bacterialization of culture broth for Bacillus sp. #72 which was sterilized at $121^{\circ}C$ for 15 minutes and than purified by $0.45{\mu}m$ membrane filter showed almost all of the antagonistic activity against Diaporthe actinidiae. We have also confirmed that in vitro treatment of Bacillus sp. #72 cultured in SD+B+P(sugar 5%, soy sauce 3%, beef extract 0.2%, peptone 0.2%) medium efficiently inhibited the growth of Diaporthe actinidiae responsible for stem-end rot in kiwi fruit.

• Korean Journal of Microbiology
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• v.45 no.2
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• pp.185-192
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• 2009

Chungkookjang fermenting Bacillus subtilis 028-1 strain suppressed the growth of Staphylococcus sp. LS2, Saccharomyces cerevisiae, and Candida albicans. B. subtilis 028-1 strain produced antibiotic effectively in the medium of 2% soybean meal and 1% maltose as a disaccharide, when the shaking was continued 15~18 h and the pH of culture medium was maintained under 6.5. The antibiotic activity was optimized when the initial pH of the culture medium of test strain was adjusted with weak alkali, was remained after 20 min of boiling and for more than 1 month in room temperature, and was weakened slowly by the digestion of chymotrypsin and papain. The molecular weight of the antibiotic was identified between 500 and 1,000 dalton by dialysis, and antibiotic substance was considered as not surfactin but a member of iturin family because of the absence of fibrinolytic activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.594-599
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• 2001

This study was attempted to isolate and identify the strain revealing high angiotensin converting enzyme (ACE) inhibitory activity from various soy fermented foods, i.e. meju, soybean paste and soy sauce. Forty-two strains with morphologically different characteristics were selected and the ACE inhibitory and proteolytic activities were examined. Of the strains tested, SS103 which was isolated from soy sauce showed the highest ACE inhibitory and proteolytic activities and was finally selected for further studies. The SS103 strain showed motility, rod form and ellipsoidal spores. The shape of colonies on the agar media was irregular, mucoidal and surface dull. The strain could grow under aerobic conditions of pH 5~9 and 10~$50^{\circ}C$. Main cellular fatty acid was $C_{15:0}$ anteiso, $C_{17:0}$ cis and $C_{17:0}$ iso, which was 33.9%, 18.8% and 16.5%, respectively. Based upon these morphological, biochemical and cultural properties, SS103 was identified as a Bacillus subtilis. Optimum cultural condition of Bacillus subtilis SS103 was pH 8.0, $37^{\circ}C$ and 48 hr.48 hr.