New research from the University of East Anglia reveals how soil bacteria build the only known enzyme for the destruction of the potent global warming and ozone-depleting gas nitrous oxide (N2O), also called laughing gas. Some soil bacteria can 'breathe' N2O in environments where oxygen (O2) is limited. This ability is entirely dependent on an enzyme, produced by the bacteria, called 'nitrous oxide reductase', which is the only enzyme known to destroy N2O. N2O has around 300 times the global warming potential of CO2 and stays in the atmosphere for about 120 years, where it accounts for around nine per cent of total greenhouse gas. It also destroys the ozone layer with similar potency to the now banned chlorofluorocarbons (CFCs). Atmospheric levels of N2O are rising year on year as microorganisms break down heavily used synthetic nitrogen fertilisers added to agricultural soil. The findings have been published in the journal Chemical Science.