This Tiny Organism Plays A Big Role In Regulating Earth’s Climate
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Ocean currents act much like a conveyer belt, transporting warm water and precipitation from the equator towards the poles and cold water from the poles back to the tropics. And now a new study, which appeared in the journal Nature Microbiology, has revealed that the bacterial group Pelagibacterales is playing an important role in the regulation of the Earth's climate.

According to researchers, Pelagibacterales are among the most abundant organisms on Earth and comprises up to half a million microbial cells found in every teaspoon of seawater. This tiny yet plentiful organism plays an important function in the stabilization of the Earth's atmosphere.

Ben Temperton, lecturer in the department of Biosciences at the University of Exeter who was a member of this research team, has also identified Pelagibacterales as a likely source for the production of dimethylsulfide (DMS) that is known to stimulate cloud formation.

The scientists added that this tiny ocean organism is also integral to a negative feedback loop known as the CLAW hypothesis. According to the study, "Under this hypothesis, the temperature of the Earth's atmosphere is stabilized through a negative feedback loop where sunlight increases the abundance of certain phytoplankton, which in turn produce more dimethylsulfoniopropionate (DMSP). This is broken down into DMS by other members of the microbial community. Through a series of chemical processes, DMS increases cloud droplets that in turn reduces the amount of sunlight hitting the ocean surface."

"This work shows that the Pelagibacterales are likely an important component in climate stability. If we are going to improve models of how DMS impacts climate, we need to consider this organism as a major contributor," said Temperton.

It must be noted that Pelagibacterales don't have the genetic regulatory mechanisms found in most bacteria.

As part of her successful PhD at the University of East Anglia, Dr Emily Fowler has conducted an extensive research on the characterization of the Pelagibacterales DMS generating enzymes. She said, "The way Pelagibacterales generates DMS is via a previously unknown enzyme, and we have found that the same enzyme is present in other hugely abundant marine bacterial species."

This study could help researchers in understanding the microbial contribution in the production of DMS gas.

(Image: Ben Temperton)