Life seems tough at hydrothermal vents deep in the ocean: crushing pressures, high temperatures and a steady flow of acidic chemicals. But life thrives. Scientists have discovered a slew of bacteria and other microbes that bask in 120-degree Celsius water. Yet, in an environment where pH levels can dip as low as 3 (acidic), scientists had not cultivated acid-loving microorganisms--until now.

Biologist Anna-Louise Reysenbach of Portland State University and her colleagues collected samples from several vent sites off the Pacific coast of South America and isolated a microorganism that seemed to persist near areas of elemental sulfur deposits. Back in the lab, the microbe flourished when allowed to propagate in a sulfur-rich, acidic environment. Further experiments showed that the Archaea-domain critters could prosper in pHs ranging from 3.3 to 5.8 and temperatures between 77 and 50 degrees C. The tiny cellular organism sports a single flagellum to propel it and an outer coating that "resembles a delicate bridal veil," the researchers write. Reysenbach and her team dubbed the microbe Aciduliprofundum boonei based on its preference for environments that are a little sour and deep as well as for David Boone, a pioneer in the study of Archaea, who recently passed away.

The existence of this acid-loving, warm water extremophile confirms yet another niche in which life can prosper, including extremes of temperature and chemical composition. It also raises the prospect that early life on the earth--or elsewhere in the universe--may have been closer to A. boonei than bacteria. The paper presenting the finding appears in today's Nature.