Growing on Carbon Dioxide

Scientists have developed a strain of E. coli that is able to produce all its cell mass from carbon dioxide. Of course, plants do this, using energy from the sun. But other organisms, including humans, normally can't. They consume other organisms, plants or animals, and use the chemicals from their food to grow. Some of the food is used to produce energy, and some is used to produce mass.

The developed strain of the bacterium E. coli uses carbon dioxide to produce mass, but it still needs an energy source. It can't use the sun. But it can use formate (a 1-carbon compound) to produce energy, and the formate can be produced electrochemically.

Now, I know some of us may feel that we produce cell mass (gain weight) just by breathing, or smelling food, but of course that's not really true. We need to eat if we want to gain weight or maintain what weight we already have, because we're constantly breaking down our mass in order to produce energy. This new type of bacteria can gain weight by using carbon dioxide as a carbon source.

The methods they used to get these new strains of E. coli are complex, but if you're interested, you can read the paper here.

The new strain still prefers glucose, rather than carbon dioxide, as a carbon source, so in the near future, this research will have very little practical application, but with time, these bacteria could be used to remove carbon dioxide from the atmosphere. E. coli bacteria are already used to produce human insulin, and if the bacteria could be grown even more cheaply because they didn't require food, just formate, perhaps the production of insulin would be cheaper. I say "perhaps" because Big Pharma would probably figure out some way to keep the insulin prices high.

But despite the lack of immediate application, this research is interesting and shows that bacteria can be trained to evolve in a way that produces some compound or compounds that we need. I just hope they don't develop greedy bacteria that can eat only chocolate. They might spread throughout my kitchen cabinets and decimate my supply.