• Microbiology and Biotechnology Letters
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• v.25 no.6
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• pp.566-570
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• 1997

During sporulation, Bacillus thuringiensis strains produce crystals consist of toxin proteins highly specific against insect pests. Their host specificities are desirable from a standpoint of environmental safety, but also limit market potential. Thus, development of improved Bacillus thuringiensis strains having broad host spectrum will contribute to increase its use. For the construction of Bacillus thuringiensis strain having broad host spectrum, we cloned cry1C gene encoding a toxin protein highly toxic against Spodoptera exigua from a B. thuringiensis isolate and constructed two recombinant plasmids, pUBClC and plC60. The plasmid PUBC1C has a replication origin of the natural plasmid pBC16 from B. cereus which is closely related species to B. thuringiensis, and the pBC16 was known to be replicated by rolling-circle mechanism. The plasmid pIC60 has a replication origin of a resident 60 MDa plasmid from B. thuringiensis subsp. kurstaki HD263, and it is believed that the pIC60 is replicated in a theta mode. The two plasmids were introduced into B. thuringiensis subsp. kurstaki cryB strain, and the transformed strains produced well-shaped bipyramidal crystals. We confirmed the expression of the cry1C gene by SDS-PAGE, and Western blotting. By investigating the segregational stability, it was found that the plasmid pIC60 is more stable than the pUBC1C.

• Korean journal of applied entomology
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• v.35 no.1
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• pp.66-73
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• 1996

For the effective control of mosquito larvae, Anopheles sinensis, the expression vector pCYASK5-1 containing cryIVD gene of Bacillus thuringiensis subsp. morrisoni PG-14 was constructed and transformed into the cyanobacterium Synechocystis PCC6803. The transformants were selected on BG-11 medium containing kanamycin. The expression of cryIVD gene in transformant was confirmed by SDS-PAGE and Western blot analysis. The mortality of A. sinensis larvae was scored for 3 days. Furthermore, growth and distribution rate of transformant were examined. The results showed that Synechocystis PCC6803 transformed with cryIVD gene of B. thuringiensis subsp. morrisoni PG-14 was highly toxic to A. sinensis larvae, demonstrating that it will be a potential agent for mosquito control.

• Korean Journal of Microbiology
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• v.39 no.3
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• pp.135-140
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• 2003

Bacillus sp. secretes high levels of extracellular enzymes into the culture medium. The signal recognition particle (SRP) and the SRP receptor play a central role in targeting pre secretory proteins to the translocase. By the analysis of the DNA microarray of B. lentimorbus WJ5, it was detected that WJ5m12, antifungal activity deficient mutant induced by gamma radiation, had a down-regulated expression of the SRP receptor gene (B. subtitis srb homologue, srbL). To determine the relationship of SRP receptor to antifungal activity, srbL of B. lentimorbus WJ5 was amplified by PCR and ligated into pQE30 vector, and then transferred into WJ5m12. The transformant, WJ5m12::srbL, recovered the antifungal activity. From the 2-DE analysis, the several presecretory proteins accumulated in the mutant cell and decreased to a level of the wild type in WJ5m12::srbL. It seems that the srbL could play an important role in the secretion of the antifungal activity related proteins of B. lentimorbus WJ5.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.5
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• pp.644-648
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• 2009

Antiproliferative effects of soy milk fermented with Bacillus subtilis from chungkukjang was studied in AGS human gastric adenocarcinoma cells. The fermented soy milk by B. subtilis (B. subtilis-F-SM) exhibited 82% growth inhibitory effect at 2 mg/mL concentration, while non-fermented soy milk (Non-F-SM) showed 68%. B. subtilis-F-SM treated AGS cells induced more apoptotic bodies than the Non-F-SM treated cells. In mRNA expressions, B. subtilis-F-SM showed decreased expression of anti-apoptotic bcl-2 and increased expression of pro-apoptotic bax. The expressions of tumor suppressor genes of p53 and p21 were also increased. These results suggest that fermented soy milk by B. subtilis exhibited higher antiproliferative activities compared with non-fermented soy milk.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.707-710
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• 2003

A strong constitutive $P_{JH}$ promoter from Bacillus was applied to overexpress the end oxylanase gene in Bacillus subtilis. The expression plasmid, pJHKJ4, was designed to contain the $P_{JH}$ promoter and endoxylanase promoter $(P_B)$, and introduced into Bacillus subtilis DB431 The total activities of the enzymes reached about 140 unit/ml by cultivation of B. subtilis DB431 harboring pJHKJ4 in LB glucose medium. Ultrafilteration is effective its yield is 70%.

• Journal of Life Science
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• v.11 no.1
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• pp.42-46
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• 2001

Subtilisin YaB, produced by alkalophilic Bacillus strain YaB, is an extracellular alkaline serine protease having 55% homology to subtilisin BPN'. It is synthesized as a 378-amino acid preproenzyme and secreted into the culture medium as a 265-amino acid mature protease. To examine the role of pro-sequence for the secretion of subtilisin YaB, we have studied the expression, in Bacillus subtilis, of a mutant preprosubtilisin YaB in which active site Ser214 is substituted with Cys. The use of a six protease-deficient strain, WB600, was required for its efficient production. The prosubtilisin YaB, thus produced, was indeed secreted into the culture medium and was processed to its mature form upon treatment with exogenously added active subtilisin YaB. From these results, we have concluded that the processing of pro-sequence is not essential for the secretion of the enzyme.

• Microbiology and Biotechnology Letters
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• v.23 no.2
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• pp.243-248
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• 1995

Agrochemicals for the plant-disease control are criticized severely for causing environmental pollution and residual problems, and consequently microbial disease control agents are expected to be safer and more economical for sustainable agriculture. Treatment of biological control agents to seed requires the use of effective delivery systems that allow full expression of the benefical qualities of the bioprotectant. For the activation and establishment of bioprotectant around the plant seed which are able protect the seeds and seedlings from pathogen attack, the optimal liquid coating formulation was obtained using 2% sodium carboxymethyl cellulose (binder), 20% sesame dregs (solid particulate material), and dried spore of Bacillus subtilis YBL-7 (bioprotectants, 10 mg/g of seed). Suppressive of root rot was demonstrated in pot trials with coated kidney bean (Phaseolus vulgaris L.) seeds. Coated seeds with B. subtilis YBL-7 spore in F. solani-infested soil reduced disease incidence by 85% to 90% after 30 days.

• Microbiology and Biotechnology Letters
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• v.21 no.2
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• pp.113-118
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• 1993

Fro the purpose of producing glouse from cellobiose or oligo saccharide and obtaining genetic information of beta-1,4-glucosidase gene, alpha beta-1,4-glucosidase gene of Pseudomonas sp. LBC505, potent cellulase complex and xylanase producing strain, was cloned in Esherichia coli and Bacillus subtilis into pUC19 and pBD64, respectively. Recombinant plasmid pGL1 contained 1.2kb EcoRI fragment was isolated from transformants forming blue color around colony on LB agar plate containing 20 ng/ml of 5-bromo-4-chloro-3-indolyl-beta-D-glucopyranoside(X-glu) and ampicillin.

• Journal of Microbiology and Biotechnology
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• v.1 no.4
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• pp.251-255
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• 1991

A 16 kilobase (kb) HindIII fragment of alkalophilic Bacillus sp. YC-335 containing a gene for xylanase synthesis was inserted at the HindIII site of pBR322 and cloned in Escherichia coli HB101. After subcloning of recombinant plasmid pYS52, the 1.5 kb fragment was found to code for xylanase activity, and the hybrid plasmid was named pYS55. The DNA insert of the plasmid was subjected to restriction enzyme mapping, which showed that pYS55 had single site for PuvII and SstI in the 1.5 kb insert fragment. Southern hybridization analysis revealed that the cloned gene was hybridized with chromosomal DNA from alkalophilic Bacillus sp. YC-335. About 64% of the enzyme activity was observed in the extracellular and periplasmic space of E. coli HB10l carrying pYS55.

• Korean Journal of Microbiology
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• v.30 no.6
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• pp.421-424
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• 1992

Escherichia coli JM83 harboring penicilin G acylase gene of Bacillus megaterium ATCC14945 produced a protein in large amount (>20% of the total protein). The protein was identified as GroEL, one of the E. coli heat shock protein, by N-terminal amino acid sequence analysis. It was found that GroEL was induced by the expressed foreign penicilin G acylase at both 27 and $37^{\circ}C$.