The nitrogenase protein complex reduces dinitrogen to ammonia by electron transfer between its subunits, switched on and off by the hydrolysis of ATP.

A newly described gene encoding a very large protein allows the malaria parasite to switch the receptor it uses for red blood cell infection, which helps in evading host defenses.

The addition of a small regulatory peptide to a transcription factor component of the circadian clock is required for its own rhythmic expression and is controlled by another clock component.