Bacterial chats limit carbon absorption by sea

Bacterial chats could significantly impact our climate by limiting the quantity of carbon dioxide absorbed by the seas from the air.

Last Updated: Oct 13, 2011, 12:14 PM IST

Washington: Bacterial chats could significantly impact our climate by limiting the quantity of carbon dioxide absorbed by the seas from the air.

Woods Hole Oceanographic Institution (WHOI) scientists made this discovery, throwing up the first ever evidence that chat among bugs plays a crucial role in our carbon cycle.

"Microscopic bacteria buffer the amount of carbon dioxide (Co2) in the air through their `conversations`," said Benjamin Van Mooy from WHOI, the journal Environmental Microbiology Reports.

"I think it`s amazing that there are a near infinite number of these conversations going on in the ocean right now, and they are affecting the Earth`s carbon cycle," added Van Mooy, according to WHOI statement.

Bacteria unite on tiny particles of carbon-rich detritus sinking through the ocean depths, sending out chemical signals to entice their cousins in the vicinity, according to WHOI marine biogeochemists Laura Hmelo, Van Mooy and Tracy Mincer.

If enough of their cohorts are nearby, they begin secreting enzymes to break up the carbon-containing molecules within the particles into more digestible bits.

Arguably, this coordinated expression of enzymes is very advantageous for bacteria on sinking particles, and Hmelo and her colleagues have uncovered the first proof of this in the ocean.

"We don`t often think about bacteria making group decisions, but that is exactly what our data suggests is happening," said Hmelo, now at the University of Washington.

The source of carbon in the particles is atmospheric CO2, a heat-trapping greenhouse gas. Bacterial communication could lead to the release of carbon from the particles at shallower depths, rather than sinking to the ocean`s depths.

IANS