# It's Life Jim, but not as we know it



## Perpetual Man (Dec 2, 2010)

A friend of mine posted this else where and I thought it was rather interesting...

NASA Finds New Life


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## Dave (Dec 2, 2010)

I agree about the importance of this. It would be the biggest thing since the Miller–Urey experiment or cracking the structure of DNA. It changes one of the Drake Equation factors quite fundamentally. Is it really true? I just watched the BBC news and no mention of this NASA conference.


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## sloweye (Dec 2, 2010)

It is Dave, just looked it up in the updates in my NASA app. 

http://www.nasa.gov/ntv


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## Starbeast (Dec 2, 2010)

Talking at the NASA conference, Wolfe Simon said that the important thing here is that this breaks our ideas on how life can be created and grow, pointing out that scientists will now be looking for new types of organisms and metabolism that now only uses arsenic, but other elements as well. She says that she's working on a few possibilities herself.




 
NASA's geobiologist Pamela Conrad thinks that the discovery is huge and "phenomenal", like comparing it to the _STAR TREK_ episode in which the Enterprise crew finds a "Horta", a silicon-based alien lifeform that can't be detected with tricorders because it wasn't carbon-based. It's like saying that we may be looking for new life in the wrong places with the wrong methods. Indeed, NASA tweeted that this discovery *"will change how we search for life elsewhere in the universe."*


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## Dave (Dec 2, 2010)

The BBC have it now:
BBC News - Arsenic-loving bacteria may help in hunt for alien life
The research is described in _Science_:
A Bacterium That Can Grow by Using Arsenic Instead of Phosphorus | Science/AAAS

Even though I love _Star Trek_ and the idea, I think Silicon replacing Carbon is less likely because carbon chemistry is quite unique, but it does open the door to other elements in the periodic table that could serve the same functions being replaced, or for Ammonia replacing Water as a solvent in cold temperatures, or just that novel kinds of DNA Nucleobases could actually exist.


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## Dave (Dec 2, 2010)

Reading more on this now, it is a little less 'Huge' than I originally thought and less than NASA is making it out to be.

Arsenic-based bacteria point to new life forms - life - 02 December 2010 - New Scientist


> Despite surviving on arsenic for a year, the bacteria would still "prefer" to grow using phosphorous: biomolecules react more efficiently in water and seem to be more stable when constructed with phosphorous than arsenic. They only substitute arsenic if there is no alternative.
> 
> Steven Benner, a chemist from the Foundation for Applied Molecular Evolution in Gainesville, Florida, who works on alternative forms of DNA, is sceptical that the bacteria really do contain arsenic. "I doubt these results," he says, since in order to measure the modified DNA it has to be put into a water-containing gel, which would rapidly dissolve any arsenate molecules. Any hypothesis that arsenate might replace phosphate in biomolecules must take this into account, he says.



So, they were causing existing bacteria to feed on the substitute element. I thought a new life-form had been discovered that had evolved along different lines. It is still important, and I do still think it increases the size of the Drake Equation factor fℓ (that fraction of planets that develop life.)

N = R* x fp x ne x fℓ x fi x fc x L 

where,

R* = the average rate of star formation per year in our galaxy
fp = the fraction of those stars that have planets
ne = the average number of planets that can potentially support life per star that has planets
fℓ = the fraction of the above that actually go on to develop life at some point
fi = the fraction of the above that actually go on to develop intelligent life
fc = the fraction of civilizations that develop a technology that releases detectable signs of their existence into space
L = the length of time such civilizations release detectable signals into space.

But, it is hardly Earth-shattering!


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## mosaix (Dec 2, 2010)

Thanks, PM. Very interesting.


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## Stephen Palmer (Dec 3, 2010)

People interested in this story might like this book:

Amazon.com: Life Ascending: The Ten Great Inventions of Evolution (9780393338669): Nick Lane: Books

I'm reading it at the moment, and I highly recommend it.


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## Nik (Dec 3, 2010)

The new bugs are interesting as an example of hyper-extremophiles (sic) but I don't think they merit NASA's hype. For one thing, the bugs still need a trace of phosphorous...

Also, IIRC, Arsenic is rarer than Phosphorous, except where concentrated by hot springs and mineral seeps...

I must wonder how the bugs have evolved enzymes that don't clog in the presence of Arsenic. My feeling is that they carry two sets of genes for their enzymes, the mutated variety being 'too loose' to hold onto phosphorous well, thus allowing Arsenic to work...

These bugs could be very useful for cleaning up toxic seeps etc, provided you could extract the arsenic without that escaping. I'm thinking of those naturally polluted Indian aquifers....


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## ScrambleEggHead (Dec 8, 2010)

There is that which we know, that which we know we don't know, and that which we don't know that we don't know.


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## Deathpool (Dec 8, 2010)

That is interesting.


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## Starbeast (Dec 8, 2010)

*It's not Life Jim, so let's forget the whole thing.*

I read an article that scientists outside of NASA are having trouble believing this "new life" finding, they think the that NASA has either bad scientists, or that NASA is still pushing their own agendas.

At this point I really could care less, I would rather have NASA pursue "alien contact" so we can work together with our galactic neighbors to help solve our world problems. Or at least tell us that the military is still heavily testing new types of aircraft, so we can stop looking at the sky hoping there is someone out there that can help us.


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