background: botulinum neurotoxin (bont) complexes consist of neurotoxin and neurotoxin-associated proteins. hemagglutinin-33 (ha-33) is a member of bont type a (bont/a) complex. considering the protective role of ha-33 in preservation of bont/a in gastrointestinal harsh conditions and also its adjuvant role, recombinant production of this protein is favorable. thus in this study, ha-33 was expr...

Clostridium botulinum serotype A produces a neurotoxin composed of a 100-kDa heavy chain and a 50-kDa light chain linked by a disulfide bond. This neurotoxin is part of a ca. 900-kDa complex, formed by noncovalent association with a single nontoxin, nonhemagglutinin subunit and a family of hemagglutinating proteins. Previous work has suggested, although never conclusively demonstrated, that neu...

Botulinum neurotoxin, produced mainly by the spore-forming bacterium Clostridium botulinum, is the most poisonous biological substance known. Here, we show that CodY, a global regulator conserved in low-G+C Gram-positive bacteria, positively regulates the botulinum neurotoxin gene expression. Inactivation of codY resulted in decreased expression of botA, encoding the neurotoxin, as well as in r...

Blocking neurotransmission, botulinum neurotoxin is the most poisonous biological substance known to mankind. Despite its infamy as the scourge of the food industry, the neurotoxin is increasingly used as a pharmaceutical to treat an expanding range of muscle disorders. Whilst neurotoxin expression by the spore-forming bacterium Clostridium botulinum appears tightly regulated, to date only posi...

Cobra neurotoxin, a short-chain peptide isolated from snake venom of Naja naja atra, showed both a central analgesic effect and a hyperalgesic effect in mice tests. In order to explore mechanisms, a hypothesis is put forward that cobra neurotoxin takes effect through adenosine receptor pathway. The central effects of cobra neurotoxin were evaluated using the hot plate test (a model of acute pai...

Botulinum neurotoxins (BoNTs) are highly potent poisons produced by seven serotypes of Clostridium botulinum. The mechanism of neurotoxin action is a multistep process which leads to the cleavage of one of three different SNARE proteins essential for synaptic vesicle fusion and transmission of the nerve signals to muscles: synaptobrevin, syntaxin, or SNAP-25. In order to understand the precise ...

BACKGROUND Botulinum neurotoxin type A (BoNT/A) is the active substance in preparations used for the highly effective treatment of neurologic disorders such as cervical dystonia, blepharospasm, or spasticity, as well as other indications such as axillary and palmar hyperhidrosis, and urologic disorders. OBJECTIVE To determine the amount of BoNT/A protein present in pharmaceutical preparations...

A postsynaptic neurotoxin was purified from Daboia russelli russelli venom using gel filtration, ion-exchange chromatography and reverse-phase high-performance liquid chromatography. The N-terminal sequence, molecular mass and pharmacological activities of the neurotoxin/cytotoxin indicate that it is a short-chain neurotoxin like that found in Elapid venom. This is the first report on the prese...

Genome sequences of five different Group II (nonproteolytic) Clostridium botulinum type F6 strains were compared at a 50-kb locus containing the neurotoxin gene cluster. A clonal origin for these strains is indicated by the fact that sequences were identical except for strain Eklund 202F, with 10 single-nucleotide polymorphisms and a 15-bp deletion. The essential topB gene encoding topoisomeras...

conclusion: the newly produced recombinant protein bmk revealed to be immunogenic. moreover, anti-bmk antibodies produced in mice were able to recognize both the recombinant bmk neurotoxin and the one in m. eupeus crude venome. taken together, the molecular characterization and recombinant production of the iranian scorpion m. eupeus venom component can serve as a new probe for further studies ...