Article: Grow in the Dark - Bottom-dwelling bacterium survives on geothermal glow

Grow in the Dark: Bottom-dwelling bacterium survives on geothermal glow
Naila Moreira

A microbe discovered in the deepest, darkest reaches of the Pacific Ocean
makes its living in an unlikely way-by photosynthesis. The newly described
species, announced in the June 28 Proceedings of the National Academy of
Sciences, uses faint light emitted by deep-sea hydrothermal vents to power
its metabolism.

A host of weird creatures lives at these vents, often called black smokers,
where volcanically heated fluids gush from Earth's crust (SN: 11/24/01, p.
331: Available to subscribers at
http://www.sciencenews.org/articles/20011124/note12.asp). But the microbe,
the only photosynthetic organism in nature known to use a light source other
than sunlight, may be among the most unexpected.\

"It expands our vision of possible environments where you could have
photosynthesis," says biochemist Robert Blankenship of Arizona State
University in Tempe.

He and his colleagues cultivated what Blankenship describes as a "beautiful,
emerald green organism" from water they'd collected from the vents of the
East Pacific Rise, which lies 2,500 meters underwater off the Mexican coast.
They'd begun searching for deep-sea photosynthesizers a decade ago, after
coauthor Cindy van Dover of the College of William and Mary in Williamsburg,
Va., discovered that hydrothermal vents emit small amounts of light.

Full text at ScienceWeek
http://www.sciencenews.org/articles/20050625/fob5.asp

Posted By
Robert Karl Stonjek


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