Black dots are micro-particles of gold collected by programmed bacteria
Researchers at Duke University (North Carolina, USA) have taught bacteria to create simple devices by programming synthetic gene chains.
A colony of such bacteria grows and takes the form of a hemisphere. At the same time, a chain of genes within bacteria triggers the "production" of a certain type of protein, the purpose of which is to collect and accumulate inorganic materials. If, after that, gold nanoparticles are introduced into the colony, the bacteria will collect from them a golden shell, the size and shape of which can be changed by adjusting the conditions for the growth of the colony.
Using this method, researchers have already managed to create a simple electronic device - a pressure sensor. To get it, scientists grew two domed structures and mirrored their bases. Then each structure was connected to an LED light through a copper wire. During the compression, the domes pressed against each other, and the resulting deformation contributed to an increase in conductivity - as a result, the light bulb lit up. The harder the pressure was, the brighter the light burned.