Saturday, April 25, 2009

exotic respiration...,

The Scientist | Members of a microbial community from a pool of water deep under the Arctic ice power their metabolism by "breathing" iron, a study in this week's Science reports. The previously unknown mechanism may explain how microbes survived during a period 600 million years ago, when the earth's oceans were covered in ice, the authors say.

The identification of the bacterial ecosystem's oddball respiration is a "remarkable discovery," said Alan J. Kaufman, a biogeochemist at the University of Maryland in College Park, who was not involved in the study. It's impressive, he said, that the group was able to "look with such detail at the microbiology of the consortium of organisms that is basically eking out a living in an environment where there's no new food."

Jill Mikucki, a geomicrobiologist at Dartmouth College in Hanover, NH, who led the research, first discovered the microbial community several years ago in a pool of marine brine seeping out from Blood Falls, a frozen, rust-laced waterfall at the mouth of the Taylor Glacier in East Antarctica.

In this study, Mikucki's team investigated the microbes' metabolism by studying their use of different minerals.