• Applied Biological Chemistry
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• 제35권4호
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• pp.227-231
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• 1992

식물병원성 사상균에 대해 길항력을 갖는 그람음성 Pseudomonas fluorescens KR164의 chromosome에 그람 양성인 Bacillus thuringiensis(BT)의 HD-1 toxin gene을 삽입하기 위하여 이 유전자를 갖는 plasmids pSUPBT과 pSUPBTR을 작성하였다. Conjugation을 이용한 transposition으로 P. fluorescens KR164의 chromosome에 이 plasmids를 삽입시켜 BT toxin 유전자를 갖는 P. fluorescens KR164의 변이균주를 조제하였다. Southern blotting으로 균주의 cellular DNAs를 조사한 결과 모든 변이균주에서 한 개 이상의 BT toxin gene의 삽입이 확인 되었으며 독소단백질의 존재 역시 SDS-PAGE에 의해서 확인되었으며 이러한 독소단백질의 결정 생성은 전자현미경에서도 확인되었다.

• 한국미생물·생명공학회지
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• 제23권4호
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• pp.390-396
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• 1995

Bacillus sphaericus 1593 is a larvicidal toxin-producing mosquitocidal bacterium. The toxin contains a parasporal crystalline inclusion which is composed of a protein that is activated under alkaline condition. To enhance alkaline environment around toxin protein, cryptic plasmid cured, B. sphaericus 1593 was transformed by the Bacillus pasteurii urease gene which generate ammonia from urea. Transformant produced urease at about 80% more than wild type strain. B. sphaericus 1593, and the urease gene was stably maintained. It also produced crystalline toxin protein at the same level as the wild type strain B. sphaericus 1593.

• International Journal of Industrial Entomology and Biomaterials
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• 제4권1호
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• pp.43-49
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• 2002

We have cloned cDNAs encoding toxin from the spider, Araneus ventricosus, and constructed a recombinant baculovirus expressing the insecticidal toxin. The cDNAs encoding toxin were cloned from the cDNA library of A. ventricosus. Sequence analysis of the cDNAs encoding the toxin of A. ventricosus revealed that the 240 bp cDNA for AvTox-1 and 192 bp cDNA for AvTox-2 have an open reading frame of 80 and 64 amino acid residues, respectively. The deduced protein sequence of the toxin genes of AvTox-1 and AvTox-2 was aligned to that of the snack Anemonia sulcata and scorpion Centruroides limpidus limpidus, respectively. Northern blot analysis indicated that AvTox-2 toxin gene showed a fat body-spe-cific expression pattern at the transcriptional level. Furthermore, we have explored the possibility of improving baculovirus by incorporating the A. vontricosus toxin gene into Bombyx mori nuclear polyhedrosis virus genome under the control of polyhedrin promoter, The AvTox-2 toxin gene was expressed as approximately 5.8 kDa band in the recombinant baculovirus-injected silkworm larvae. Bioassays with the recombinant virus expressing AvTox-2 on 5th instar silkworm larvae demonstrated a decrease in the time to kill $(LT_{50} days)$ compared to wild-type BmNPV-Kl $(LT_{50} 6.72 days)$ in the injection of 10 viruses. These results indicate that A. ventricosus toxin is a novel member of the spider toxin family, suggesting that the toxin gene can be used in recombinant baculoviruses to reduce insect feeding damage and increase the speed of insect kill.

• 한국식품영양학회지
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• 제9권4호
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• pp.459-465
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• 1996

지금까지 많은 연구가 되어 있지 않던 Bacillus thuringiensis serovar. darmstadiensis의 내독소를 Renografin-76 단계적 기울기 원심분리로 분리하여 전자 현미경으로 관찰하여 이중피라미드 구조를 가진 독소 단백질을 확인하였으며 B. thuringiensis serovar. kurstaki HD1의 독소 생성유전자와 B. thuringiensis serovar. darmstadiensis의 유전자가 유사성이 있다는 보고를 근거로 하여 B. thuringiensis serovar. HD1의 독소 생성유전자를 가진 프로브(pUYBT 9044)로 이용하여 colony hybridization 및 Southern hybridization 한 결과 2.6Kb EcoRI 단편 및 3.6Kb Hind III 단편을 선발할 수 있었다. 이들 단편들은 B. thuringiensis serovar. kurstaki HD1 독소 유전자와 hybridization시 유사성이 있었다. 특히 3.5Kb HindIII 단편은 2.6Kb EcoR I 단편에 클로닝되어 있는 1.8Kb의 HD1 독소 유전자와 유사성이 있는 부분을 공유하고 있었으며 1.0Kb 정도의 EcoR I-HindIII 부분이 더 삽입한 것을 알 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제27권8호
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• pp.1449-1456
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• 2017

The prevalence and toxin characteristics of Bacillus thuringiensis isolated from 39 organic vegetables were investigated. B. thuringiensis was detected in 30 out of the 39 organic vegetables (76.9%) with a mean value of 2.60 log CFU/g. Twenty-five out of the 30 B. thuringiensis isolates (83.3%) showed insecticidal toxicity against Spodoptera exigua. The hblCDA, nheABC, and entFM genes were found to be the major toxin genes, but the ces gene was not detected in any of the tested B. thuringiensis isolates. The hemolysin BL enterotoxin was detected in all 30 B. thuringiensis isolates (100%). The non-hemolytic enterotoxin complex was found in 27 out of 30 B. thuringiensis isolates (90.0%). The B. thuringiensis tested in this study had similar toxin gene characteristics to B. cereus, which possessed more than one toxin gene. B. thuringiensis could have the potential risk of foodborne illness based on the toxin genes and toxin-producing ability.

• Journal of Plant Biotechnology
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• 제6권1호
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• pp.21-24
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• 2004

A modified $\delta$-endotoxin gene of Bacillus thuringiensis ssp. tenebrionis (B.t.t.), encoding a coleoptera-specific toxin, was utilized to transform citrus plants, Citrus reticulata Blanco 'Ponkan' mandarian. By co-culturing the nucelli with Agrobacterium tumefaciens harboring the modified gene in the binary vector pBinAR-Btt, the chimeric toxin gene was transferred into citrus plants. The transgenic plants were selected on modified Murashige and Skoog medium containing kanamycin. Hybridization experiments demonstrated that the transgenic plants contained and expressed the toxin protein gene.

• Applied Biological Chemistry
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• 제41권2호
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• pp.137-140
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• 1998

딱정 벌레목 유충에 살충성을 나타내는 형질 전환 토마토 식물체를 4세대까지 분자 육종을 하였다. 분자 육종된 4세대 식물체에서 살충성 유전자인 B.t.t. 독소 유전자와 유전자가 발현되는 것을 확인하였다. 이 4세대 형질 전환 식물체는 독소 유전자 발현에 의해 딱정 벌레 유충에 살충성을 나타내고 있음이 확인 되었고, 4세대 형질 전환 식물체는 염색체는 2 배수체로 확인되어 정상적인 토마토 식물체임이 증명 되었다. 이 결과들은 형질 전환에 사용된 독소 유전자가 다음 세대로 안정되게 유전되고 있음을 나타내고 있다는 증거이다. 이러한 형질 전환된 식물체의 분자 육종은 농업에 있어서 현재의 일시적인 해충 방제에 비해 장기적인 해충 구제에 대한 새로운 방법의 가능성을 제시하고 있다고 하겠다.

• 한국수산과학회지
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• 제56권6호
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• pp.826-832
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• 2023

Clostridium perfringens causes diarrhea and other diseases in humans and animals. We investigated the prevalence, toxin gene profiles, and antimicrobial resistance of C. perfringens isolated from commercial jeotgal sample. C. perfringens was isolated from 11 of 22 commercial jeotgals. All C. perfringens strains were positive for the alpha toxin gene, but not for the beta, epsilon, iota, CPE or NetB toxin genes; therefore, all strains were identified as type A C. perfringens. However, the beta2 toxin gene was identified in 54.5% of isolates. Disk diffusion susceptibility tests showed that most isolates were resistant to kanamycin (90.9%), nalidixic acid (72.7%), oxacillin (54.5%), erythromycin (27.3%), ciprofloxacin (9.1%) and clindamycin (9.1%). However, all strains were susceptible to 14 other antimicrobial including amoxicillin, ampicillin, and chloramphenicol. The average minimum inhibitory concentrations against C. perfringens of clindamycin, kanamycin, and nalidixic acid were 128.0, 128.0, and 54.0 ㎍/mL, respectively. These results provide new insight into the necessity for sanitation of commercial jeotgal, and provide evidence to help reduce the risk of contamination with antimicrobial-resistant bacteria.

• Toxicological Research
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• 제13권4호
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• pp.417-421
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• 1997

Synaptobrevin is a kind of vesicle associated membrane proteins (VAMPs) which plays a secretary role in the neuronal synapse and was recently known as the biochemical target of botulinum neurotoxin type B. The structural gene of the synaptobrevin was cloned from mouse brain using RT-PCR technique and was seqrtenced. The deduced amino acid sequence showed that the synaptobrevin protein from mouse brain is exactly the same with that of the rat brain in the amino acid level. The synaptobrevin gene was subcloned into pET3a vector and expressed in E. coli. The molecular weight of the recombinant protein was 19 kDa as expected. Moreover, when the recombinant synaptobrevin protein was incubated with the native neurotoxin of Clostridium botulinum type B, it was cleaved by the toxin in a time dependent manner. This implies that the recombinant synaptobrevin protein and the native toxin are reacted in the same way as the native synaptobrevin did in the neuronal cells.

• Journal of Microbiology
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• 제44권3호
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• pp.320-326
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• 2006

Pasteurella multocida is an important veterinary and opportunistic human pathogen. In particular, strains of P. multocida serogroup D cause progressive atrophic rhinitis, and produce a potent, intracellular, mitogenic toxin known as P. multocida toxin (PMT), which is encoded by the toxA gene. To further investigate the toxigenic and pathogenic effects of PMT, a toxA-deleted mutant was developed by homologous gene recombination. When administrated to mice, the toxigenicity of the toxA mutant P. multocida was drastically reduced, suggesting that the PMT constributes the major part of the toxigenicity of P, multocida. Similar results were obtained in a subsequent experiment, while high mortalities were observed when toxA(+) P. multocida bacterial culture or culture Iysate were administrated. Mice immunized with toxA(-) P. multocida were not protected (none survived) following challenge with toxA(+) P. multocida or bacterial culture Iysate (toxin). These results suggest that the toxigenicity of P. multocida is mainly derived from PMT.