On the face of it, this seems an unlikely proposition. Natural sources of radio waves include lightning, stars and pulsars while artificial sources include radar, mobile phones and computers. This is a diverse list. So it’s hard to see what these things might have in common with bacteria that could be responsible for making radio waves.
But today, Allan Widom at Northeastern University in Boston and a few pals, say they’ve worked out how it could be done.
They point out that many types of bacterial DNA take the form of circular loops. So they’ve modelled the behaviour of free electrons moving around such a small loop, pointing out that, as quantum objects, the electrons can take certain energy levels.
Widom and co calculate that the transition frequencies between these energy levels correspond to radio signals broadcast at 0.5, 1 and 1.5 kilohertz. And they point out that exactly this kind of signal has been measured in E Coli bacteria.