A research team led by Pierre Rustin in Paris, together with Howy Jacobs in the Institute of Biotechnology have released startling findings about the temperature of mitochondria inside our cells. Although the body as a whole is maintained at a relatively cool 37 °C, the power plants of our cells, mitochondria, operate at a much higher temperature, a sizzling 50 °C.– This discovery requires us to rethink a lot of conventional biochemistry, says Jacobs. The findings should have great importance for understanding how mitochondrial dysfunction impacts human health. They also invite us to reconsider how biological systems cope with extreme temperatures and with the wide fluctuations in temperature and nutrition that are common in the natural environment. The work is reported on the pre-print server BioRxiv (doi.org/10.1101/133223), and is currently under peer-review at a leading journal. Howy Jacobs, director of the Institute of Biotechnology, University of Helsinkitel. +358 02941 59359, firstname.lastname@example.org