Novel structure of a subtype of the botulism neurotoxin could be used to enhance therapeutics

摘要

Scientists from the US Department of Energy's (DOE) Brookhaven National Laboratory (NY, USA) have discovered the structure of the botulism neurotoxin subtype E, a deadly toxin produced by specific bacteria that is often used to calm hyperactive bladder. Its components are arranged in a different way to the other serotypes and this distinct structure could lead to greater therapeutic potential.The bacteria, Clostridium botulinum produces seven distinct neurotoxins that have similar functionality and 3-D structures. The subtypes share a common mechanism to produce their deadly effects, with each step carried out by a specific protein domain. First the toxin binds to a nerve cell. It moves into the cell and cleaves specific proteins, blocking the release of neurotransmitters. Without these transmitters, communication between nerve cells and muscles breaks down and the result is paralysis. When you consider that this can take place in the cells controlling breathing you can see why the toxin causes fatalites.