Happy Spring
 |
Snow flakes can have bacteria
at the center |
As Spring gets started and the American midwest is hopeful that the snow will finally melt away and
the Polar vortex of the 2014 winter will be done already, there's a bacterium--
Pseudomonas syringae-- that can
control the weather, cause
frost damage to plants, and it also bears the distinction of being the
first GMO approved for release to the environment. In fact, this bacterium might even explain the ice powers of
Elsa in
Frozen -- maybe she just had the right bacteria at her fingertips.
Snow -- and hail and rain -- can be caused by bacteria. It's not that bacteria are synthesizing the water, but bacteria can serve as the nucleation point, encouraging water molecules to surround them and form a droplet. This means that all those unique snowflakes have a structure something like a Tootsie roll pop. Except instead of a candy center, when you catch a snowflake on your tongue and it melts away, the delicious center is a tiny cluster of bacteria.
Controlling the Weather
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| Making it rain |
This may seem like an idle curiosity, but the implications of this are actually pretty amazing. Bacteria could potentially help us control the weather. Bacteria (or the proteins they use to nucleate water) are already used in snow machines at ski resorts, and have been used in some pilot studies to look at
using drones to seed the air around Lake Tahoe with bacteria to encourage more snow to fall. If approaches like this are successful, one could imagine a future where we actually coax rain from clouds to alleviate drought.
The Frost Queen
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Snow machines make use of
bacterial technology |
The organism responsible for water nucleation is most often
Pseudomonas syringae, and it's an organism everyone should know. In order to make it rain, this organism has to survive up in the atmosphere miles above the surface--and it does. How does it get there? Well, it primarily grows on the surfaces of plant leaves, and is accustomed to getting blown around by the wind so that it can colonize new plant leaves. But it's not always benevolent.
P. syringae is a pathogen for many species of plant, and it's ability to encourage ice to form means that it is often responsible for frost damage killing plants.
The First GMO
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| Bacteria encourage frost during cold snaps |
P. syringae also bears the distinction of being
the first genetically modified organism (GMO) approved to be released into the environment, back in 1987. The idea was to spray crops with mutants that lack the ice-nucleating proteins. It worked, and protected the plants from damage, but as far as I know wasn't cheap enough to go on to wide spread use.
