A unique strain of Clostridium botulinum serotype D 4947 produces toxin complexes that are composed of un-nicked components, including a neurotoxin (BoNT) and auxiliary proteins. This BoNT showed aberrant elution upon Superdex gel filtration, indicating a much lower molecular weight, due to hydrophobic interaction with the column. Limited trypsin proteolysis of BoNT produces two nicks; first nick yielded a BoNT 50 kDa light chain disulfide linked to a 100 kDa heavy chain (Hc), and a second nick arose in Hc C-terminal 10 kDa. The second nick occurred in the putative binding domain of the BoNT molecule and induced alterations in its secondary structure, leading to a significant reduction of mouse toxicity in comparison with that of the fully-activated singly nicked BoNT. These results help to clarify the role of the C-terminal half of the Hc in the oral toxicity of single-chain and more complex forms of BoNT.
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http://dx.doi.org/10.1007/s10930-006-9059-7 | DOI Listing |
Int J Mol Sci
January 2025
Botulinum Research Center, Institute of Advanced Sciences, Dartmouth, MA 02747, USA.
Botulinum toxin (BoNT), the most potent substance known to humans, likely evolved not to kill but to serve other biological purposes. While its use in cosmetic applications is well known, its medical utility has become increasingly significant due to the intricacies of its structure and function. The toxin's structural complexity enables it to target specific cellular processes with remarkable precision, making it an invaluable tool in both basic and applied biomedical research.
View Article and Find Full Text PDFGeorgian Med News
November 2024
1Department of biology, College of Education for Women, University of Kirkuk, Iraq.
Background: Botulinum toxin is an attenuated neurotoxin of Clostridium Botulinum gram positive bacterial, which is used in medication sialorrhea, cervical dystonia, hyperhidrosis and non-surgical cosmetic operation (aesthetic) such as facial wrinkles and reduced the bulky appearance hypertrophied of masseter muscle. This study was designed to revealed the effect of zygomiticus inoculation of botulinum toxin B in zygomatic muscle of rats on zygomatic bone.
Methods: A total of 25 male albino rats (200-260 gm) were injected facial intramuscular by a single dose of 2.
Vaccines (Basel)
January 2025
Division of High-Risk Pathogens, Department of Laboratory Diagnosis and Analysis, Korea Disease Control and Prevention Agency, KDCA, Cheongju 28159, Republic of Korea.
Background: Botulinum neurotoxins (BoNTs), produced by , are potent protein toxins that can cause botulism, which leads to death or neuroparalysis in humans by targeting the nervous system. BoNTs comprise three functional domains: a light-chain enzymatic domain (LC), a heavy-chain translocation domain (HC), and a heavy-chain receptor-binding domain (HC). The HC domain is critical for binding to neuronal cell membrane receptors and facilitating BoNT internalization via endocytosis.
View Article and Find Full Text PDFMedicine (Baltimore)
January 2025
Department of Rehabilitation Medicine, Hebei General Hospital, Shijiazhuang, Hebei, China.
Rationale: Steven-Johnson syndrome (SJS) is characterized by severe illness, rapid progression, and high mortality rates, with the vast majority of cases induced by medications. Botulinum toxin, a neurotoxin produced by Clostridium botulinum, has not been reported in the literature as a causative agent of SJS.
Patient Concerns: A 56-year-old male patient, who underwent surgery for cerebral hemorrhage, developed widespread patchy annular papules following the injection of botulinum toxin into the masseter muscle.
Poult Sci
January 2025
Ploufragan-Plouzané-Niort Laboratory, Epidemiology Health and Welfare Unit, French Agency for Food, Environmental and Occupational Health and Safety (ANSES), BP53 22440 Ploufragan, France. Electronic address:
Appropriate disposal of dead farming animals is required to guarantee effective disease control while protecting the environment. In crisis situations, alternatives to rendering can be used, including on-farm burial. The objectives of this study were to: (i) describe the burial and monitoring protocols used on poultry farms in France in response to major avian influenza outbreaks; (ii) assess the effectiveness of the burial protocol, in terms of both technical and biosecurity aspects, and microbiological, physical and chemical changes of the buried materials and the environment over time; (iii) provide recommendations for future burial and follow-up protocols.
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