The enzyme co-substrate S-adenosylmethionine is a potential source of two different free radicals, yet only one seemed to occur in nature. The discovery of an unusual enzyme reveals that both radicals can be formed.

The groundwork for analysing the human microbiome — sequencing the collective genome of all our resident microorganisms — is now done. This work is of significance for understanding both human health and disease.

Losses in biodiversity and the emergence of new infectious diseases are among the greatest threats to life on the planet. The declines in amphibian populations lie at the interface between these issues.