# NASA discovers new lifeform with totally different DNA than anything else

by Simfish
Tags: discovers, lifeform, nasa, totally
 P: 489 What would happen if we ate this bacteria? Would it be like eating arsenic?
 P: 112 Well yes but assumeing you cleansed it off first it would be a extreemly dilute dose, however if you were to dip your hand in the lake im pretty sure it could end badly.
 P: 1,641 Thanks for that. The first sentences of the five points make pretty clear to me that arsenic is playing a role in their biochemistry. I wonder though how robust the bacteria are? Does the arsenic provide any clear advantage to their continued evolutionary success even in the most friendly environments to their biochemistry or would they quickly become extinct if their cozy salt lake changed even slightly? Perhaps though the answer is obvious: most (complex) life on (average) earth is phosphate-based and therefore, I would guess, the arsenic, although interesting, is probably not a viable adaptive strategy against sometimes drastically changing environments that phosphate-based organisms have been so successful at overcoming.
P: 2,490
 Quote by madcat8000 Are the implications that it uses arsenic in every way the same as it uses phosphorus or only in certain select aplications? Do they use Adenotriarsenate instead of Adenotriphosphate? IMHO if it only uses arsenic where its convienient and easy then its a cute biochemical trick, but if it uses ATAs......thats a real biochemical revolution!!!
This article says that the native Mono Lake bacteria were cultured in an As rich, phosphorus poor environment. In the cultured bacteria As does replace phosphorus (P) in ATP yielding ATAs. I don't know if this is the case in the native strains, but if it isn't, then it detracts from the significance of this discovery. In any case, it's still not all that remarkable. Now silicon replacing carbon, that would be something!

P: 21,694
 Quote by jackmell Perhaps though the answer is obvious: most (complex) life on (average) earth is phosphate-based and therefore, I would guess, the arsenic, although interesting, is probably not a viable adaptive strategy against sometimes drastically changing environments that phosphate-based organisms have been so successful at overcoming.
Note that abundance of P on Earth is about 1000 higher than As. In most environments there is plenty of P available (as compared to As).

http://en.wikipedia.org/wiki/Abundan...nts_(data_page)

Also note numbers listed are mass fractions, we should be looking at molar fractions, that would mean even twice less As.

So even if they were interchangeable, P would be preferred just because of its availability.
 P: 1,641 Ok, then what about just bond energies. Take just ATP and ATA. What is the energy difference in cleaving a phosphate off of ATP and a what $AO_4$ off of ATA? What about the phosphate-ribose bond in nucleic acids? What is the energy difference in the analogous $AO_4$-ribose bond? Would be interesting to know if it's less or more than for phosphate. If it's less, then these molecules are less stable. If it's more, then the energy required would perhaps cause other species in the surrounding medium to be susceptible to this energy abundance causing them to be less stable. I assume in this particular bacteria, these energy adjustments and associated (chemical) species have adapted through Natural Selection. Just how much adaptation is needed to account for this energy difference?
 P: 112 Yeah i wonder if it would be possible to produce a media that would have almost no trace of phosphate.
 PF Patron Sci Advisor Emeritus P: 11,137 Someone's got to do it: Source: http://xkcd.com/829/
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P: 2,949
 Quote by Gokul43201 Someone's got to do it: Source: http://xkcd.com/829/
Arg. Beat me by 5 mins. I'll post the mouse-over text then.

According to a new paper published in the journal Science, reporters are unable to thrive in an arsenic-rich environment.
 P: 2 Research Sugar - I believe it came from another planet - It destroys the human Body - Think I'm pulling your chain? - Read this http://www.science20.com/news_releas...egion_g3141031
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