Stressed-out bacteria make difficult decisions

We may think of bacteria as rather dull, thoughtless organisms, but when the going get tough it seems that they are able to weigh up their options and make life or death decisions. 

Biologists at Rice and Tel Aviv University, led by Dr José Onuchic, have found that faced with life-threatening conditions, such as drought or radiation, the majority of bacteria (around 99%) will choose the safe option and enter a state of dormancy. A few, however, will take a gamble and remain active.

The bacteria used in this study - Bacillus subtilis

So what defines a bacterium that will play it safe versus a risk-taker? To understand this, the researchers identified some of the genes and proteins involved in decision-making, which gave them a clearer understanding of the process.

It is thought that bacteria communicate with each other via chemical signals and can use these to assess each other’s condition – so if a bacterium becomes dormant, its neighbour can tell. As more bacteria become dormant there is less competition for dwindling resources, and a minority of bacteria, sensing that their neighbours have become dormant, will take advantage of this and decide to remain active.

It is hoped that this research may provide an insight into how cells in our own body work – we know that they too communicate via chemical signals, and it may be they are using these to make complicated decisions concerning our health and ability to tackle disease.