via +Carlos Toscano Ochoa 1 year old, but still interesting work by an iGEM team:
"Although our project is pretty ambitious, it is also certainly feasible. We are going to build circuits based on collections of different bacteria strains, where each strain works as a logic gate. A logic gate is the basic component of an electronic circuit, such as AND, OR or XOR, and it exchanges information with the others.Combining the correct strains and using certain chemical substances as system inputs we can manipulate a bacterial community into performing complex functions.
To achieve our goal we are going to define a standard of programming modularized biological circuits, where a community of bacteria from different but interconnected strains form a physically independent module. Combining different modules in this way makes it possible to recycle strains and substances. To implement this system, the key is to standardise the inter-modular communication substances. This is exactly what we are going to do: we are going to define a substance, which we have named the Universal BioBit (or Ubbit for short), that will be the element of communication between modules. Just like that, any research group could use the modules created by any other group and combine them with their own without the necessity of knowing how it internally works, just by using the Ubbit standard."