Re: Is there a bacteria that uses hydrogen as its energy source?

Hi Sam,

Thanks for your question. The quick answer is yes - there are microorganisms that use hydrogen as an energy source. Such organisms are called hydrogenotrophs, or are described as hydrogenotrophic. I mention those words because they are specific terms which will help you when you're searching the Web for more information.

Hydrogenotrophs can be bacteria, but they are more commonly archaea. Archaea are prokaryotic, single-celled microorganisms that resemble bacteria in appearance, but genetically, have many features in common with eukaryotes (organisms with a membrane-bound nucleus, such as ourselves!) In fact they are different enough that they are grouped together in their own separate kingdom of life.

As you indicated, methane from cows is generated by methanogens, which are archaea. However, these organisms are also the "hydrogen-eating" organisms - the hydrogenotrophs. They generate energy by combining hydrogen with carbon dioxide, producing methane as a by-product. So for your plan to work, you would need to introduce a micro-organism that used hydrogen more efficiently than the methanogens, or was able to out-compete them. Or another approach would be to introduce a methanotrophic species - one which could consume the generated methane.

All organisms generate energy by oxidising a chemical compound and then getting rid of the electrons generated by reducing a second compound. Humans, for example, oxidise sugars and reduce oxygen to water. Bacteria and archaea are very metabolically versatile - there are species that can grow given almost any element or compound as an energy source. Your challenge will be to find the correct combination and one that is able to survive and thrive inside the cow.