Life Down Under ... Zero, That Is

Courtesy of Brian Oakley

Researchers say they have identified bacteria thriving at the lowest temperatures for which such activity is documented. Several such ultracold microbe findings are making the possibility of life elsewhere in the Solar System seem less distant and are presenting new biotechnological possibilities.

The University of Washington's James Staley and colleagues say they cultured rod-shaped bacteria, tentatively named Psychromonas ingrahamii, from off Alaska's coast, at -12°C.¹ Populations doubled every 10 days, Staley says, making this temperature the lowest for which growth has been "authenticated with a growth curve."

Pennsylvania State University researchers report finding various bacteria and archaebacteria alive in 120,000-year-old ice from 3 km below Greenland's surface. At about -9°C, temperatures there were downright balmy by P. ingrahamii's standards. The bacteria appear to have survived other harsh stresses, including desiccation and pressure, reported Penn State's Vanya Miteva and Jean Brenchley last month...