The fewer resources available on the planet, the more daring the flight of thought of scientists becomes. A pair of researchers from the Stevens Institute of Technology in New Jersey, USA, designed a mold with a bioluminescent glow function. And this is not an achievement of gene architecture, but an engineering structure, an applied passive power plant.
The first layer of the "mushroom" is 3D printed from ink interspersed with pieces of graphene, it is the basis. The second one is printed on top of ink with cyanobacteria. You can choose any pattern for printing both layers, but there are two conditions: the layer with live bacteria must be accessible for irradiation with light and have intersection points with the lower layer.
When light hits the bacteria, the process of photosynthesis is triggered, due to which free electrons are formed, which flow through the contact points to the conductor with graphene. Their movement generates an electric current, very weak, of the order of 65 nanoAmperes. But it is enough to make a couple of LEDs glow, and since the initial energy is free, with the help of arrays of such mushrooms and suitable weather, you can illuminate an entire room for quite some time.
Aesthetically similar generators and lamps look controversial - like smears of dirt on a wall lit by the sun. But if you provide them with an influx of water and nutrients, then bacteria can not only survive, but also multiply. In general, the project opens up scope for creative experimentation.