Detoxification of a bacterial toxin by the toxin itself

Several bacterial protein toxins act by forming oligomers on the cell surface. A novel approach to the prevention of the damage caused by oligomeric pore-forming toxins has recently been discovered using one such protein: the protective antigen (PA) of Bacillus anthracis. Some PA mutants act as dominant-negative effectors of the function performed by the oligomer. In fact, the PA mutant co-oligomerizes with native PA, but the mixed oligomer is nonfunctional. This finding might turn out to be of general validity.