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Elisa Granato
Bacteria are aggressive organisms that have evolved a host of draconian ways to kill and inhibit their competitors. One of the most extreme of these strategies is where cells actively break themselves apart and die to release large toxins that kill other strains. While it was known that some bacteria do this, the extent of the behaviour was not known and it was typically assumed that only a few cells would perform these suicidal attacks.
A new study, published today in Current Biology, shows this is far from the case: in some areas of bacterial battlegrounds, almost all cells will kill themselves to generate a massive simultaneous attack.
Suicidal behaviours are very rare in the natural world and it is typically hard to understand why they would evolve. This study reveals that millions of bacteria will simultaneously engage in a suicidal behaviour. Moreover, it shows that this occurs in the best studied of all bacteria: the common gut bacterium, Escherichia coli. This discovery has striking similarities to behaviours seen in social insects, bee and ant