Friday, June 15, 2012

Dry Dry again

The word of the day today is Desiccation.

Desiccation means to remove all of the water from something, or to make it really dry. Beef jerky= dessicated, egyptian mummies= dessicated, the last turkey I tried to cook= desiccated.



Now, humans, and most other organisms for that matter, don't do well when it comes to drying out. That's why drinking fluids is so imporatnt. If we don't replentish the water we loose we dry out and die.

What if you are an organism that lives in a dessert where there is very little water? Well, dessert organisms have developed some pretty ingeneous/crazy adaptations to find and conserve as much water as possible.

What if you happen to live somewhere even drier than that, like say... The McMurdo Dry valleys?



The McMurdo Dy Valleys are among the driest places on the planet. They barely even get snow. There are some lakes, but all of them are extremely salty, some are even saltier than the Dead Sea, making them impossible to drink. Even the ominously named blood falls make it seem as if nothing could live there.

For more pictures of Blood Falls CLICK HERE!

 Yet, things do. Specifically fungi. Despite the super-harsh conditions, many species still manage to thrive.

How do they do it? It's quite simple really. Many of these fungi have adapted so they can be dried out. When they dry out they enter a sort of stasis. Once water is added again, they moisten back up and continue growing and reproducing.  BAM! Instant fungus. 

From the makers of Rotten Crawfish Juice.

We here at Connell Lab, have decided to test the resiliency of some of these organisms. We are doing this by taking various fungi we have collected and drying them out. After a week or two of desiccation we add water to them and see how many have survived.

Now, you may be thinking, "That's cool and all, but why should we care?"

Good question.

 Dr. Rodrı ́guez-Porrata from The Department of Biochemistry and Biotechnology at The University Rovira, (et al), suggested that since fungi are actually surprisingly closely related to humans, if we can learn how fungi preserve themselves by drying out, we may be able to do something similar. That doesn't mean spraying King Tut with a garden hose to bring him back to life mind you. Dr. Rodrı ́guez-Porrata suggests that we could use what we learn to create more effective way of preserving red blood cells for transfusions.

Now comes in four unique flavors!

Beyond that though, desiccation resistance helps provide evidence for a pretty awesome hypothesis called Lithopanspermia.

In short, lithopanspermia is a hypothesis that suggests that organisms are capable of traveling from one planet to another by, for example, traveling on asteroids knocked off from other planets.

It may seem a little far fetched, but it's actually not as crazy as it sounds. Dr. Onofri of the Università degli Studi della Tuscia, Largo dell’Universita, (et al), suggests that in order to survive in space, an organism would need to be able to survive, desiccation,  large changes in temperature, exposure to UV radiation, and of course exposure to a vacuum. Some preliminary research showed that some Antarctic fungus could survive these conditions. To further test this hypothesis, Dr. Onofri's team are putting fungi samples on the outside of the International Space Station to see if they can actually survive in space.

Please understand that, if the samples do come back alive, that is not definitive evidence that life originated on another planet, it will simply prove that we can't say it didn't.


By Ben Segee

Citations: B. Rodriguez-Porrata, D. Camona-Gutierrez, A. Reisenbichler, M. Bauer, G. Lopez, X. Escote, A. Mas, F. Madeo, R. Cordero-Otero (2011): Sip18 hydrophilin prevents yeast cell death during desiccation stress, Journal of Applied Microbiology, 112, 512-525.

 S. Onofri1, D. Barreca, L. Selbmann, D. Isola, E. Rabbow,  G.  Horneck, J.P.P. de Vera,  J.  Hatton and L. Zucconi, (2008): Fungal Biodiversity Center, 99-109.

S. Onofri, L. Selbmann, D. Barreca, D. Isola & L. Zucconi (2009): Do fungi survive under actual space conditions? Searching for evidence in favour of lithopanspermia, Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology: Official Journal of the Societa Botanica Italiana, 143:sup1, S85-S87

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