Microbes floating among clouds may munch on sugar

Floating in a cloud and noshing sweets while wrapped in a cozy bubble sounds like a pleasant dream. For some lucky bacteria, it may be a reality.

Researchers have discovered that a cloud-dwelling microbe, in this case a species of Bacillus bacteria, can eat up the sugars floating around in the atmosphere.

The microbes, plucked from clouds above the Auvergne region of France, were known to be metabolically active, but their diets were a mystery. Back in the lab, the researchers provided a feast of carbohydrates commonly kicked into the atmosphere by Earthlings. The bacteria broke down the heavenly sweets and reused the molecular rubble as building blocks for protective polysaccharide coatings. Those coatings, which may shield the microbes from ultraviolet radiation and frigid temperatures, may also spur droplet formation in clouds, which could alter atmospheric processes, the authors report Nov. 12 in Environmental Science & Technology.