• Korean journal of applied entomology
• /
• v.47 no.2
• /
• pp.175-184
• /
• 2008

To screen highly active Bacillus thuringiensis isolates against Spodoptera litura (Lepidoptera, Noctuidae), 46 B. thuringiensis was isolated from 115 samples obtained from several crop soils. Especially, B. thuringiensis subsp. kurstaki CAB133 and CAB162 isolates showed 100% mortality against S. litura. $LD_{50}$ values of CAB 133, CAB162 and HD-1 strains of B. thuringiensis subsp. kurstaki were 0.089, 3.144 and $0.513{\mu}g/ml$ against 2nd larva of S. litura, respectively. The weight of 3rd larva of S. litura which were fed crystal inclusion protein $(1.267{\mu}g/ml)$ with B. thuringiensis subsp. kurstaki CAB133 was about 30 times lass than control group. CAB133 and CAB 162 strains of B. thuringiensis subsp. kurstaki which were taken a highly toxity against S. litura were analyzed by SDS-PAGE, and estimated the molecular weight of the Cry proteins. Their serological identification by H serotypes were showed B. thuringiensis subsp. kurstaki (3abc) type.

• Microbiology and Biotechnology Letters
• /
• v.19 no.3
• /
• pp.303-307
• /
• 1991

The hemolyic polypeptide in delta-endotoxin from Bacillus thun'ngiensis subsp. darmstadiensis 73ElO-2 was purified by Sephadex G-IOO gel filtration and DEAE-cellulose ion exchange column chromatography. The purity of hemolysin was confirmed by ouchterlony test and SDS-PAGE. The molecular weight of the purified hemolysin was approximately 64 KDa by SDS-PAGE. The purified hemolysin has not mosquitocidal activity against larvae of Aedes agypti, but hemolytic activity on red blood cells of rat. There is no serological relationship between delta-endotoxin from B. thuringiensis subsp. israelensis and the purified hemolysin from the . strain 73ElO-2.

• Microbiology and Biotechnology Letters
• /
• v.14 no.4
• /
• pp.325-328
• /
• 1986

The lethality to Pieris raepi larvae and the safety tests to mice of the endotoxin crystals and the pesticide of B thuringiensis serovar kurstaki were carried out. The LD50 of the endotoxin (3.9$\times$10$^9$ spores/$m{\ell}$) appeared to be 1$\mu$g and that of the pesticide (2.6$\times$10$^9$ spores/$m{\ell}$) was about 9 $\mu$g. When the endotoxin solution and the pesticide were injected to the mice's intraperitoneal cavities, 10 to 20% of the mite were dead. Also in the case of intracerebral injection 20% of the mice were dead at the doses of 7.8$\times$10$^3$ spores and 100% of the mice were dead at the concentration of 7.8$\times$10$^8$ spores. but the mice in the oral, subcutaneous and inhalation treatment groups were safe and healthy. When the pesticide applied to the cabbage field for raepi larvae, 52 to 65% of the larvae in the field were killed in 4 days postapplication.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.9 no.2
• /
• pp.183-186
• /
• 2004

Recently, we have developed an easy, simple and convenient circular DNA cloning system named plasmid capture system (PCS). To investigate usefulness of PCS in cloning of plasmids from Bacillus thuringiensis strains, PCS donors, pPCS-S and pPCS-L were applied to clone plasmids of B. thuringiensis subsp. israelensis by in vitro transposition using 4{TnsABC^*}$ transposase. In result, 3 small plasmids were cloned, and these were consistent with pTX14-1, pTX14-2 and pTX14-3 reported previously from B. thuringiensis subsp. israelensis. Therefore, the PCS can be successfully applied to clone small plasmids from B. thuringiensis strains.

• Journal of Life Science
• /
• v.6 no.4
• /
• pp.293-298
• /
• 1996

Thirteen subspecies of Bacillus thuringiensis including B. t. israelensis, B. t. morrisoni PG-14 and B.t. darmstadoemsos known to be toxic to dipteran insects were treated on the mushroom (Flammulina velutipes) compost to estimate the biological control effect of a sciarid fly, Lycoriella sp. According to the results, it was found that there were no significant effects of the tested strains of B, thuringiensis on the control of Lycoriella sp. For further confirmation, larval gut juice of Lycoriella sp. and trypsin were respectively treated into the parasporal crystal proteins of three subspecies of B. t. israelensis, B. t. morrisoni PG-14, and B. t. darmstadiensis. The proteins were separated by SDS-PAGE. According to the results, the major parasporal crystal proteins were respectively produced by B. t. morrisoni as the amount of 52 kd, B. y. israelensis as 37kd and B. t. darmstadiensis as 39kd, but the activity of these proteins could not be unfortunately confirmed in this study.

• Journal of Microbiology and Biotechnology
• /
• v.16 no.11
• /
• pp.1713-1719
• /
• 2006

A method for the simple, rapid, specific, and accurate detection of Bacillus anthracis spores was developed by employing specific capture peptides conjugated with fluorescent quantum dots (QDs). It was possible to distinguish B. anthracis spores from the spores of B. thuringiensis and B. cereus using these peptide-QD conjugates by flow cytometric and confocal laser scanning microscopic analyses. For more convenient high-throughput detection of B. anthracis spores, spectrofluorometric analysis of spore-peptide-QD conjugates was performed. B. anthracis spores could be detected in less than 1 h using this method. In order to avoid any minor yet false-positive signal caused by the presence of B. thuringiensis spores, the B-Negative peptide, which can only bind to B. thuringiensis, conjugated with another type of QD that fluoresces at different wavelength was also developed. In the presence of mixed B. anthracis and B. thuringiensis spores, the BABA peptide conjugated with QD525 and the B-Negative peptide conjugated with QD585 were able to bind to the former and the latter, specifically and respectively, thus allowing the clear detection of B. anthracis spores against B. thuringiensis spores by using two QD-labeling systems. This capture peptide-conjugated QD system should be useful for the detection of B. anthracis spores.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.8 no.1
• /
• pp.61-66
• /
• 2004

Bacillus thuringiensis 656-3 which was isolated from a soil sample of mushroom house and showed high toxicity to mushroom flies, Lycoliella mali and Coboldia fuscipes, was surveyed for insecticidal effect in the oyster mushroom house.3. thutingiensis 656-3 was mass-cultured in the fermenter containing soybean cake(2%) and wheat bran (2%) as media source. Semi-for-mutation of B. thuringiensis 656-3 was performed with metamorphic starch only. When the formulation suspension containing $5{\times}{10^7}$ cfu was sprayed on the mushroom in mushroom house, the insecticidal effect of B. thuringiensis 656-3 to mushroom flies,1. mali and C. fuscipes, was maintained over 90% by the fifth day after starting spraying. The yield of oyster mushroom house with B. thuringiensis 656-3 was significantly increased compared to control. B. thuringiensis 656-3 represents a powerful biological insecticide for the control of mushroom flies.

• Journal of environmental and Sanitary engineering
• /
• v.12 no.2
• /
• pp.59-64
• /
• 1997

For purification of a 70kDa toxic protein of mosquitocidal delta-endotoxin from B. thuringiensis strain H9B, immuno-affinity chromatography was performed. After separation of 70kDa toxic proteins from the delta-endotoxin of the strain H9B on SDS-PAGE, the 70kDa toxic protein was subcutaneously injected into rabbit for making a polyclonal antibody. A anti-70kDa toxic protein was purified by a column chromatography packed with protein A-sepharose 4B gels. The 70kDa toxic protein from delta-endotoxin of the strain H9B was also purified by an immuno-affinity chromatography packed with CNBr-activated sepharose 4B gels conjugated anti-70kDa toxic protein after elution with 1/10M citric acid-1/5M Na$_{2}$HPO$_{4}$ buffer(pH3.2) containing 0.5M NaCl. The 70kDa toxic protein was purified through only one step-separation system, was demonstrated by SDS-PAGE and immunoblot.

• Korean journal of applied entomology
• /
• v.48 no.4
• /
• pp.509-517
• /
• 2009

Bacillus thuringiensis subsp. aizawai CAB109 isolated in Korea is known active against Spodoptera sp.. Especially, B. thuringiensis aizawai CAB109 isolates showed 100% mortality against Spodoptera litura and Spodoptera exigua. To screen highly active B. thuringiensis, the pathogenicity of B. thuringiensis CAB109 was compared with that of commercialized B. thuringiensis products. $LC_{50}$ values of CAB109, product TB-WP and product SC strains of B. thuringiensis were $1.3{\times}10^5$, $2.3{\times}10^6$ and $5.2{\times}10^5\;cfu/ml$ against the 2nd larva of S. litura and $1.8{\times}10^4$, $1.3{\times}10^6$ and $1.5{\times}10^6\;cfu/ml$ against the 2nd larva S. exigua, respectively. To determine new gene's existence and absence, the plasmid DNA was extracted, and compared to that of B.t. aizawai HD-133. Both B. thuringiensis were not like plasmid DNA pattern. PCR technique was used to predict both plasmid DNA's cry gene. PCR products analysis showed that B.t. CAB109 harbor Cry1Aa, Cry1Ab, Cry1C and Cry1D and B.t. HD-133 has Cry1Aa and Cry1Ab, respectively.

• Microbiology and Biotechnology Letters
• /
• v.27 no.5
• /
• pp.359-363
• /
• 1999

To prevent appearance of resistant mosquitoes against $\delta$-endotoxin of bacillus thuringiensis subsp. israelensis (Bti) in field, a mosquitocidal Bacillus thuringiensis strain 21-2(Bt21-2) producing a new type of $\delta$-endotoxin was isolated. The strain Bt 21-2 belongs to H serotype 43, B. thuringiensis subsp. guiyangiensis (Btg). The $\delta$-endotoxins from the strain Bt 21-2 and the strain Bti were a cuboid shape morphologically, but the $\delta$-endotoxin of the strain Bt 21-2 was composed of 150, 90 and 70kDa proteins on SDS-PAGE, and the antigenicity of $\delta$-endotoxin of the strain Bt 21-2 was different from that of the strain Bti on immunoblot. The $\delta$-endotoxin gene of the strain Bt 21-2 was not amplified with specific primers of $\delta$-endotoxin gene (cry4A and cry4B) of the strain Bti on PCR.