• Food Science and Preservation
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• v.7 no.4
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• pp.414-417
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• 2000

Competent cell transformation of B. subtilis AC819 was carried out using phenotypic protease-defective(Npr-) DNA of B. subtilis MT-2. An obtained transformant, designated B. subtilis HL-1, was obtained by homologous DNA recombination. Phenotypes of B. subtilis HL-1 were characterized histidine requirement streptomycin-resistance, tetracyclin resistance and non-producing protease. Protoplast transformation frequency of B. subtilis HL-1 by plasmid pUB110 was higher than that of B. subtilis MT-2. From this result, B. subtilis HL-1 is useful for protease gene transformation and thermostable protease gene cloning as a host.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.3
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• pp.526-533
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• 1999

Two species of antimicrobial agent producing bacteria and one sensitive strain were isolated from soil. Those were identified as B. subtilis, B. licheniformis, and Curtobacterium sp. by morphological, biochemical, physiological and chemotaxonomic characteristics. These were designated as B. subtilis cx1, B. licheniformis cy2 and Curtobacterium sp. cf3, respectively. Antimicrobial agent produced by B. subtilis cx1 showed high antibacterial activity against gram positive bacteria including of B. subtilis, Curtobacterium sp., L. mesenteroids, Staphy. aureus, S. faecalis and even gram negative bacteria, P. aeruginosa. Antimicrobial agent from B. licheniformis cy2 showed slightly lower antimi crobial activity than that from B. subtilis cx1. These two strains showed maximum production of antimicrobial agents at 30oC for 9~21hr cultivation. Curtobacterium sp. cf3 showed more sensitive activity than a sensitive strain of B. subtilis ATCC 6633 which was same genus or species with the B. subtilis cx1 and B. subtilis cy2, when the antimicrobial agent producing strains, B. subtilis cx1 and B. subtilis cy2, were directly applied onto these sensitive lawns.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.326-331
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• 2010

Bacillus subtilis B29, B. subtilis M10 and Streptomyces sp. CC19 obtained from phyllosphere of cucumber plants were selected for biological control of fungal air-borne diseases. For the downy mildew, diseased area of B. subtilis B29, B. subtilis M10 and Streptomyces sp. CC19 showed 0.5%, 20.2% and 42.0%, but that of control was 82.0% respectively, in cucumber seedling test. Incidence of powdery mildew by once application of B. subtilis B29, B. subtilis M10 and Streptomyces sp. CC19 was 2.8%, 3.6% and 12.3%, respectively, whereas that of control was 65.6%. On the gray mold, diseased area of B. subtilis B29, B. subtilis M10 and Streptomyces sp. CC19 was 8.0%, 30.8% and 5.2%, respectively, compared to 81.2% for the control. Therefore, B. subtilis B29 could be a prospective antagonist for biological control of powdery mildew, downy mildew and gray mold of cucumber plant.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.873-878
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• 2002

In order to industrialize traditional Meju-tasting Koji, the characteristics of Koji manufactured with bacteria and fungi found in traditional Meju were investigated. Bacillus subtilis B-4 and Aspergillus oryzae F-5 showing high enzyme activities including those of amylase and protease were used. L-value of Koji manufactured with B. subtilis B-4 had darker color and higher enzyme production than A. oryzae F-5 made one. B. subtilis B-4 made Koji showed higher enzyme production and sensony evaluation score than A. oryzae F-5 Koji. A. oryzae F-5 Koji showed superior color to B. subtilis B-4 Koji. Activity in color, capacity of enzyme production, viable cell count, and sensory evaluation of water activity controlled Koji was superior to the uncontrolled one.

• Microbiology and Biotechnology Letters
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• v.34 no.3
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• pp.221-227
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• 2006

BSCX1 was an antimicrobial peptide produced by Bacillus subtilis cx1. Attempts were made to determine the location of inducing factor in the bacteriocin-sensitive cell affecting bacteriocin BSCX1 production. Mixed culture of the bacteriocin producer strain B. subtilis cx1 and its sensitive strain B. subtilis ATCC6633, increased production of bacteriocin BSCX1. The result suggested the presence of a bacteriocin inducing factor in the sensitive strain. The inducing factor was localized in the cell debris and intracellular fraction of B. subtilis ATCC6633. Bacteriocin BSCX1 inducing factor was found to be highly stable in the pH range 2.5-9.5, but inactivated within 3h over $50^{\circ}C$, and treatment with proteinase K destroyed its inducing activity, this result suggested that the inducing factor should be a proteinaceous nature.

• Journal of fish pathology
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• v.26 no.3
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• pp.185-191
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• 2013

The present study was performed to investigate an antibacterial activity of specific bacteriophage (phage) and Bacillus subtilis KM-1 (B. subtilis) mixture against Edwardsiella tarda (E. tarda). An appropriate number of phage showing the most effective antibacterial activity was $2{\times}10^5$ PFU/ml with $1{\times}10^7$ CFU/ml of B. subtilis 36 h post incubation. On the other hand, B. subtilis showed a dose dependant manner in inducing antibacterial activity in the presence of phage ($2{\times}10^5$ PFU/ml). The phage and B. subtilis mixture showed higher antibacterial activity against E. tarda than phage or B. subtilis only. These results suggest that the phage and B. subtilis mixture could be utilized as an alternative to antibiotics in the control of fish diseases caused by E. tarda.

• Journal of Microbiology and Biotechnology
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• v.17 no.10
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• pp.1688-1694
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• 2007

A gene encoding the mannanase of Bacillus subtilis WL-3, which had been isolated from Korean soybean paste, was cloned into Escherichia coli and the nucleotide sequence of a 2.7-kb DNA fragment containing the mannanase gene was subsequently determined. The mannanase gene, designated manA, consisted of 1,080 nucleotides encoding a polypeptide of 360 amino acid residues. The deduced amino acid sequence was highly homologous to those of mannanases belonging to glycosyl hydrolase family 26. The manA gene was strongly expressed in B. subtilis 168 by cloning the gene downstream of a strong B. subtilis promoter of plasmid $pJ27{\Delta}88U$. In flask cultures, the production of mannanase by recombinant B. subtilis 168 reached maximum levels of 300 units/ml and 450 units/ml in LB medium and LB medium containing 0.3% locust bean gum, respectively. Based on the zymogram ofthe mannanase, it was found that the mannanase produced by recombinant B. subtilis could be maintained stably without proteolytic degradation during the culture time.

• Microbiology and Biotechnology Letters
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• v.47 no.4
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• pp.498-508
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• 2019

Bacillus species were isolated from iru, a traditional fermented condiment in Nigeria. Polyphasic approach was used to evaluate the phylogenetic relationship and strain sub-type of the isolated species. Additionally, the phylogenetic profiles of the species isolated from iru were compared with those of bacilli isolated from different continents. The phylogenetic diversity analysis was performed using the combination of 16S rRNA gene sequencing, ITS-PCR, ITS-PCR-RFLP, and M13 RAPD-PCR. The analysis revealed that Bacillus subtilis U170B and B. subtilis U146A isolated from iru were the closest relatives of strains belonging to the phylogeny of B. subtilis sensu stricto and were related to other bacilli isolated from different continents that had functional benefits. The two isolated species exhibited resistance to acidic pH (pH 2.0). The survival rates of B. subtilis U170B, B. subtilis U146A, and B. clausii UBBC-07 (commercial probiotic strain) cultured at pH 2.0 for 3 h were 33.45, 12.44, and 9.53%, respectively. The strains were highly tolerant to bile salts [0.3% (w/v)]. B. subtilis U170B exhibited the highest cell viability (43.45%) when cultured for 3 h in the presence of bile salts, followed by B. subtilis U146A (25%) and B. clausii UBBC-07 (18.94%). B. subtilis U170B and B. subtilis U146A did not exhibit haemolytic activity and were susceptible to different antibiotics. Additionally, these two strains exhibited weak antagonistic activity against B. cereus. The diverse wild strains of B. subtilis can be used as a safe multifunctional starter culture for the industrial production of condiments with health benefits.

• Current Research on Agriculture and Life Sciences
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• v.31 no.1
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• pp.30-37
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• 2013

Bacillus subtilis and Bacillus amyloliquefaciens are closely related species that share a similar genomic background, and are both known to secrete large amounts of proteins directly into a medium. The extracellular proteomes of two strains of Bacillus subtilis and two strains of Bacillus amyloliquefaciens were compared by 2-D gel electrophoresis during the late exponential growth phase. The relative abundance of some minor protein spots varied among the four strains of Bacillus. Over 123 spots of extracellular proteins were visualized on the gel for B. subtilis CH 97, 68 spots for B. subtilis 3-5, 230 spots for B. amyloliquefaciens CH 51, and 60 spotsfor B. amyloliquefaciens 86-1. 2D gel electrophoresis images of the four Bacillus strains showed significantly different protein profiles. Consistent with the 2D gel electrophoretic analysis, most of the B. subtilis proteins differed from the proteases secreted by the B. amyloliquefaciensstrains. Among the proteins identified from B. subtilis, approximately 50% were cytoplasmic and 30% were canonically extracellular proteins. The secreted protein profiles for B. subtilis CH 97 and B. subtilis 3-5 were quite different, as were the profiles for B. amyloliquefaciens CH 51 and 86-1. The four proteomes also differed in the major protein composition. The B. subtilis CH 97 and B. amyloliquefaciens CH 51 proteomes both contained large amounts of secreted hydrolytic enzymes. Among the four strains, B. subtilis 3-5 secreted the least number of proteins. Therefore, even closely related bacteria in terms of genomic sequences can still have significant differences in their physiology and proteome layout.

• Journal of Microbiology and Biotechnology
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• v.28 no.10
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• pp.1760-1768
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• 2018

The type strain Bacillus subtilis subsp. subtilis KCTC $3135^T$ was deeply sequenced and annotated, replacing a previous draft genome in this study. The tar and tag genes were involved in synthesizing wall teichoic acids (WTAs), and these genes and their products were previously regarded as the distinguishing difference between B. s. subtilis and B. s. spizizenii. However, a comparative genomic analysis of B. subtilis spp. revealed that both B. s. subtilis and B. s. spizizenii had various types of cell walls. These tar and tag operons were mutually exclusive and the tar genes from B. s. spizizenii were very similar to the genes from non-Bacillus bacteria, unlike the tag genes from B. s. subtilis. The results and previous studies suggest that the tar genes and the tag genes are not inherited after subspecies speciation. The phylogenetic tree based on whole genome sequences showed that each subspecies clearly formed a monophyletic group, while the tree based on tar genes showed that monophyletic groups were formed according to the cell wall type rather than the subspecies. These findings indicate that the tar genes and the presence of ribitol as a cell-wall constituent were not the distinguishing difference between the subspecies of B. subtilis and that the description of subspecies B. s. spizizenii should be updated.