• Journal of Microbiology
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• v.41 no.2
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• pp.161-164
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• 2003

Recombinant light chain of Clostridium botulinum neurotoxin type B stimulated transglutaminase activity in a dose dependent manner, Compared to native toxin, recombinant light chain showed av greater stimulatory effect on transglutaminase activity. Zn-chelating agents, inhibiting the proteolytic activity of the clostridial toxins, did not interfere with this stimulation. These results suggest that the light chain plays a major stimulatory role, which is not due to its metallopeptidase activity, but is possibly due to specific interaction with transglutaminase. More importantly, this report provides a new insight into the intracellular action of C. botulinum neurotoxins.

• Toxicological Research
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• v.13 no.4
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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.

• Molecules and Cells
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• v.22 no.3
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• pp.336-342
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• 2006

Real time reverse transcription (RT)-PCR was used to quantify the expression of the botulinum neurotoxin type A (BoNT/A) gene (cntA) by normalization with the expression of 16S rRNA. The method were confirmed by monitoring the mRNA levels of cntA during growth in five type A strains. In all but one of the strains the expression of cntA mRNA was maximal in the late exponential phase, and approximately 35-fold greater than in the early exponential phase. The concentration of the extracellular BoNT/A complex detected by ELISA was highest in stationary phase. Sodium nitrite and sorbic acid completely inhibited growth at 20 ppm and $4mg\;ml^{-1}$, respectively. CntA expression became lower in proportion to the concentration of sorbic acid, and this reduction was confirmed by mouse bioassay. Our results show that real time RT-PCR can be used to quantify levels of C. botulinum type A neurotoxin transcripts and to assess the effects of food additives on botulinal risk.

• Journal of Microbiology and Biotechnology
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• v.13 no.2
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• pp.287-291
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• 2003

Botulinum neurotoxin type A (BONT/A) is an extremely potent toxin, which is produced by Clostridium botulinum. The light chain of this protein (BONT/A LC), which is known as a zinc endopeptidase, cleaves SNAP-25 involved in the exocytosis process. In this work, the expression of recombinant BoNT/A LC in E. coli is described. The BONT/A LC gene of C. botulinum contains a high frequency of the arginine AGA and isoleucine ATA codons that are rarely used in genes of E. coli, hampering the translation of recombinant protein. The argD and ilex tRNA genes were cloned into pACYC184 vector, resulting in pAAD131X plasmid. The translational stress of the toxin gene related to codon bias was reversed by fupplernentation of the AGA arginyl tRNA of T4 phage and AUA isoleucyl tRNA of E. coli. This system may be applicable for the expression of a variety of AT-rich heterologous genes in E. coli.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.295-301
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• 2017

Botulinum neurotoxin (BoNT/A) is a neurotoxin that selectively attacks the peripheral cholinergic nerve endings. It is produced by Gram -positive, endospore-forming strict anaerobic bacteria, Clostridium botulinum. Since BoNT/A could be a biothreat agent, as well as a contaminator of food and water supplies, the development of sensitive assays for toxin detection and potent antitoxin for the treatment of intoxication is necessary. In this study, for the purpose of producing monoclonal antibodies (mAbs) that are capable of neutralizing Botulinum neurotoxin type A (BoNT/A), scFv (single-chain variable domain fragment) libraries from the rabbit antisera against BoNT/A was fused to a human IgG. The resulting recombinant scFvIgG antibody protein was expressed in stable cell lines and was purified using a protein A affinity chromatography. The efficacy of scFvIgG mAb was confirmed by ELISA and was evaluated for the neutralization of BoNT/A in vivo. Such an in vivo toxin neutralization assay was performed using mice. Although scFvIgG antibody proteins (10 ug) failed to fully protect the mice challenged with BoNT/A (100,000 $LD_{50}$), it significantly prolonged the survival time. These results suggest that scFvIgG mAb may be capable of neutralizing BoNT/A single-chain variable domain fragment.

• Food Science and Biotechnology
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• v.15 no.4
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• pp.499-505
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• 2006

Clostridium botulinum spores are widely distributed in nature. Type A and proteolytic type B bacteria produce heat-resistant spores that are primarily involved in most of the food-borne botulism outbreaks associated with low-acid canned foods. Food-borne botulism results from the consumption of food in which C. botulinum has grown and produced neurotoxin. Growth and toxin production of type A and proteolytic type B in canned foods can be prevented by the use of thermal sterilization alone or in combination with salt and nitrite. The hazardousness of C. botulinum in low-acid canned foods can also be reduced by preventing post-process contamination and introducing hazard analysis and critical control point (HACCP) practices during production. Effectiveness of non-thermal technologies such as high pressure processing with elevated process temperatures on inactivation of spores of C. botulinum will be discussed.

• The Journal of the Korean dental association
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• v.41 no.12 s.415
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• pp.826-830
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• 2003

botulinum toxin type A는 anaerobic bacterium clostridium botulinum에서 유래된 poly peptide neurotoxin으로서 사시, 안면연축, 수부다한증등에 치료목적으로 안정적으로 사용되어오다 최근에는 이마주름, 눈가주름등 주름살의 개선 목적으로 널리 사용되어 오고있다. 특히 턱얼굴외과 영역에서는 이러한 주름살의 개선이외에도 사각턱, 안면 신경의 이상으로 인한 안면 비대칭등 적용범위가 상당히 넓고 치료효과도 만족할 만하다고 하겠다. 이에 턱얼굴외과의사 나아가 치과의사들의 많은 사용을 기대하여 botulinum toxin 사용의 역사적 배경, 약리 및 작용기전, 가능한 합병증, 턱얼굴영역에서의 적용가능성 등에 대해 알아보고자 한다.

• Proceedings of the KSLP Conference
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• 2002.04a
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• pp.75-82
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• 2002

Botulinum toxin-A, a neurotoxin derived from Clostridia Botulinum, has been injected into the laryngeal muscle(s) for the treatment of the spasmodic dysphonia at the Voice Clinic, Yonsei Institute of Logopedics and phoniatrics since December 1995. We analyzed 355 patients with spasmodic dysphonia, using Botox register review. In the 355 patients, female is 86.8%. male is 13.2%. 305 patients (85.9%) had adductor type of spasmodic dysphonia and 35 patients (9.9%) were vocal tremor type and 15 patients were abduction and mixed type. Botulinum toxin type-A (Botox) injection using EMG was most frequently conducted as 587 cases, comparing with flexible nasopharyngoscopy gudied injection (68cases) and tele- laryn-goscopy guided injection (31cases). In the respect of frequency of Botox injection, 137 patients(38.6%) were injected one time but 1 patient was injected 17times. The mean dose of Botox is 6.2U. Clinically, initial dose of Botulinum toxin-A was high dose (7-8U) but current dose is small dose (3U). And the mean duration of Botox injection is 6.4 month. In conclusion, to optimize effect of the treatment for spasmodic dysphonia, Botulinum toxin-A injection is combined with voice therapy.

• Speech Sciences
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• v.3
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• pp.5-17
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• 1998

Botulinum toxin, a neurotoxin derived from Clostridia Botulinum, has been injected into the target muscle(s) for the treatment of several kinds of voice and speech disorders at the Voice Clinic, Yonsei Institute of Logopedics and Phoniatrics since December 1995. Criteria for the diagnosis and method of injection for spasmodic dysphonia, mutational dysphonia, muscle tension dysphonia, dysphonia after total laryngectomy, and stuttering were summarized. Among 144 patients with adductor type spasmodic dysphonia, who were injected one time to maximum 8 times during the 27 months, 90% were recognized as having better than slight improvement. Even though the injected cases were small, not only the abductor type spasmodic dysphonia, but also the intractable mutational dysphonia or muscle tension dysphonia resistant to voice therapy revealed that botulinum toxin injection would be another options for treatment. Patients who cannot phonate after total laryngectomy and some forms of adulthood stutterers can also be candidates for the injection of botulinum toxin.

• Korean Journal of Microbiology
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• v.20 no.4
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• pp.183-188
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• 1982

The neurotoxin of Clostridium botulinum type B was purified from a liquid culture. The purification steps consist of ammonium sulfate precipitation of whole culture, treatment of Polymin P(0.15%, v/v), gel filtration on Sephadex G-100 at pH5.6 and DEAE-Sephadex charomatography at pH8.0. The procedure recovered 17% of the toxin assayed in the starting culture. The toxin was homogeneous by sodium dodecyl sulfate(SDS)-polyacrylamide gel electrophoresis and had a molecular weight of 163, 000. Subunits of 106, 000 and 56, 000 molecular weight were found when purified toxin was treated with a disulfide-reducing agent and electro phoresed on SDS-polyacrylamide gels.