Life in hydrogen

For the first time, yeast and Escherichia coli have been shown to not only survive but thrive in a 100% hydrogen atmosphere. The findings suggest that life could exist even on exoplanets with a hydrogen-rich atmosphere.

Neither E coli nor yeast are adapted to living under hydrogen, although both can grow in anaerobic conditions. Researchers have now grown the two microorganisms in solutions saturated with hydrogen inside bottles also filled with the gas. Both species survived and even reproduced, albeit more slowly.

E coli grew half as fast in hydrogen as in air, but faster than in a nitrogen/carbon dioxide atmosphere. This is because carbon dioxide acidifies the growth medium. Yeast cells were affected more severely, growing two and a half times faster in air than under hydrogen or nitrogen/carbon dioxide. Without oxygen, yeast can’t synthesise certain chemicals such as haem and sterols, and rely on external sources of these compounds.

Use the starter slide with your class to help them explore the connection between the atmosphere of planets and the life on them.

Read the full story in Chemistry World.