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NASA Earth Science

NASA Confirms Discovery of Organism With Phosphorus-Free DNA 380

Posted by timothy
from the well-it's-not-that-shaggy dept.
GNUALMAFUERTE writes "As we mentioned before, NASA's Department of Astrobiology had an important announcement to make today. It looks like Gizmodo was right. You can watch the presentation online right now. It looks like the bacteria in question uses arsenic as a phosphorus replacement in its DNA."
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NASA Confirms Discovery of Organism With Phosphorus-Free DNA

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  • by Anonymous Coward on Thursday December 02, 2010 @03:55PM (#34421762)

    It's life Jim, but not as we know it.

  • Neat, but... (Score:5, Insightful)

    by mikaelwbergene (1944966) on Thursday December 02, 2010 @03:56PM (#34421770)

    This is neat and clearly an important discovery and all, but I'd be lying if I said I wasn't a little bit disappointed.

    • by ultranova (717540) on Thursday December 02, 2010 @03:59PM (#34421832)

      This is neat and clearly an important discovery and all, but I'd be lying if I said I wasn't a little bit disappointed.

      Cheer up, the broadcast is still going. They're just using the phosphorus-free DNA as a red herring to make the final part more shocking. You know, the last minute where they reveal Bush tied to a chair, take a good grip on his nose, and pull off the human mask to reveal a reptilian overlord beneath.

      • by albeit unknown (136964) on Thursday December 02, 2010 @04:16PM (#34422164)

        This is neat and clearly an important discovery and all, but I'd be lying if I said I wasn't a little bit disappointed.

        Cheer up, the broadcast is still going. They're just using the phosphorus-free DNA as a red herring to make the final part more shocking. You know, the last minute where they reveal Bush tied to a chair, take a good grip on his nose, and pull off the human mask to reveal a reptilian overlord beneath.

        and he would have gotten away with it if it weren't for you meddling kids!

      • by Bob9113 (14996) on Thursday December 02, 2010 @04:33PM (#34422436) Homepage

        where they reveal Bush tied to a chair, take a good grip on his nose, and pull off the human mask to reveal a reptilian overlord beneath.

        Don't they have to rip the Obama mask off first to reveal Bush underneath?

      • Re:Neat, but... (Score:5, Insightful)

        by Obfuscant (592200) on Thursday December 02, 2010 @05:16PM (#34423038)
        You know, it gets a bit old and stale, and quite a bit tiring, for this gratuitous political-based bashing, here in a blog intended for "news that matters" for "nerds".

        It's depressing to come to a discussion about some new discovery in science just to find a long and boring thread with Bush (or Obama) bashing as the goal.

        • Re:Neat, but... (Score:5, Informative)

          by c6gunner (950153) on Thursday December 02, 2010 @05:36PM (#34423388)

          It wasn't "political based bashing", it was a joke at the expense of David Icke and his weirdos. And it was damn funny, too.

        • by ultranova (717540)

          You know, it gets a bit old and stale, and quite a bit tiring, for this gratuitous political-based bashing, here in a blog intended for "news that matters" for "nerds".

          I dunno if Bush has arsenic in his DNA, but he sure is arsenic for the rest of us.

          That's bashing. "Bush/Obama/Michael Jackson/The Pope/Richard Dawkins is a reptilian overlord" is a (non-malicious) joke. See the difference?

    • by MBCook (132727)
      Yesterday, some show on NPR asked their correspondents to to guess what the announcement would be, and I liked theirs better. Here are the three I can remember:
      • It's actually pronounced NAY-sa, not NA-sa
      • All astronauts can actually fly. If you put a normal person in space, they would still be bound by gravity
      • We've known the moon was made of cheese, but no one suspected it is actually made of Cheeze-Wiz
    • Re: (Score:2, Funny)

      This is what girls used to tell me... always.
    • by semiotec (948062)
      It's because the Gizmodo write-up is a hyperbolic piece of crap.

      ... a bacteria whose DNA is completely alien to what we know today.

      Bullshit. That's not what's claimed, and the DNA structure is still essentially the same, except that phosphorus has been replaced by arsenic. And it has been theorized, just not found until now.

      but at least they have now removed the stupid sentence which said:

      this discovery does indeed change everything we know about biology.

      It's like they were practicing writing script for some crappy sci-fi B movie.

  • made of arsenic.

  • Someone get a fire engine, some Selenium, and David Duchovney.

    • by Nidi62 (1525137)
      I think no one was happier with this announcement than Head and Shoulders. Probably should have bought some stock in them.
  • Not Phosphorus-Free (Score:5, Informative)

    by Elder Entropist (788485) on Thursday December 02, 2010 @03:58PM (#34421828)

    It replaces MOST phosphorus atoms with arsenic, but not all.

    • by SleazyRidr (1563649) on Thursday December 02, 2010 @04:02PM (#34421904)

      But it's still a carbon-based life-form right?

      (Not that I'm trying to diminish this, I think it's awesome. Just trying to get my facts straight.)

      • by dtmos (447842)

        Yes.

      • by jfengel (409917) on Thursday December 02, 2010 @04:08PM (#34422036) Homepage Journal

        That's correct. The carbons (and hydrogens and oxygens and nitrogens) are all where they should be. It's only the phosphorus that has been swapped out, for arsenic (right below it on the periodic table).

        In fact arsenic is toxic to you precisely because it takes the place of phosphorus so easily, without doing all of the jobs. Except for this little guy, who manages to work around the differences and survive nearly phosphorus-free.

        • by pi_is_after_you (857195) <lnxpeng@gmaiNETBSDl.com minus bsd> on Thursday December 02, 2010 @04:12PM (#34422118)
          That's what surprises me. If it's on the same column, it will have roughly the same properties and fit in the same reactions, but have vastly different reaction rates and affinities. So, does this thing replace phosphorous in DNA/RNA, ATP, and phospholipids? What about phosphorylation? /p.s. This is my first post to slashdot in approximately 4 years
          • From what I remember hearing they specifically mentions DNA RNA and ATP I didn't hear mention of the other two specifically, but that might be because I'm at work and listened while working. (Mostly the only reason I remember the ATP is because they made a joke about students knowing what that was.)
            • by ColdWetDog (752185) on Thursday December 02, 2010 @04:42PM (#34422526) Homepage
              It doesn't appear that they have got to the fun bits yet. Research is pretty much at the overview stage. They appear to have some crystallography data that suggests that the arsenic is bound to the DNA which suggests it's replacing the phosphorus backbone, but I don't see anything that shows the critter has replaced ATP (Adenosine TriPhosphate, the cellular power source) with Adenosine TriArsinate.

              Of course, one doesn't expect research to just dump everything out at once, there are many years of digging through this to sort it out.

              If arsenic is really powering the bacterium, then it's pretty impressive because the thing seems to grow at about 60% of maximum rate in a phosphate depleted source.
        • by MichaelSmith (789609) on Thursday December 02, 2010 @04:26PM (#34422340) Homepage Journal

          In fact arsenic is toxic to you precisely because it takes the place of phosphorus so easily, without doing all of the jobs. Except for this little guy, who manages to work around the differences and survive nearly phosphorus-free.

          Makes me wonder if this is an organism which has adapted to tolerate the damage from arsenic which would kill us.

          • by robotkid (681905) <alanc2052@ySTRAWahoo.com minus berry> on Thursday December 02, 2010 @06:01PM (#34423770)

            Makes me wonder if this is an organism which has adapted to tolerate the damage from arsenic which would kill us.

            This organism, almost certainly not. Most of these extremophiles are miserably slow growers (the doubling time was ~2 days vs 20 minutes for E. coli), so unless there's a niche somewhere in your body that allows the extremophile's adaptations to be a major advantage, it would never gain a foothold in your body as the many strains of bacteria we symbiotically live with will outcompete it for resources.

            But as to the more general question of whether any dangerous extremophiles exist out there - this is a recurring topic of speculation (over beer) amongst those that work with pathogenic microbes. Consensus seems to be that it's not impossible that an extremophile such as an archaea, or, in this case, a protobacteria could potentially be an opportunistic pathogen as well, but we haven't found one yet so it's probably not a common occurrence. The organism in this press release is a distant, distant cousin of helicobacter Pylori, an acid-loving bacteria which causes ulcers and is linked with gastric cancer, so it's not insane to think it could happen. Just unlikely.

      • by Mindcontrolled (1388007) on Thursday December 02, 2010 @04:09PM (#34422062)
        Well, as much as anything is carbon based, yes. We are carbon-hydrogen-oxygen-nitrogen-sulfur-phosphorus-based, this one is carbon-hydrogen-oxygen-nitrogen-sulfur-phosphorus/arsenic-based. That still makes for a major metabolic difference, but it is still biologically related to us. Same tree of life. Still way cool, though.
      • by yincrash (854885)
        Correct, but the panel considers it on par with finding a silicon-based life form ala star trek.
      • by sam_handelman (519767) <skh2003 AT columbia DOT edu> on Thursday December 02, 2010 @04:15PM (#34422154) Homepage Journal
        Yes, it is still carbon-based.

          In fact, this appears to be a biochemically-interesting but seriously overhyped discovery.

          AFAICT, this organism still uses the same genetic code, the same nucleotide bases, the same ribose sugars, the same everything - only this organism performs a chemical modification of the phosphate backbone, substituting in arsenic. This is only moderately different from the chemical modifications that we make to our own DNA, RNA and proteins (methylation, for example.)

          That's not a particularly shocking substitution, from a chemical standpoint, and doesn't really say anything about the viability of an organism with an actually *alien* biochemistry. Now, if you look at the periodic table, you'll see that Arsenic is right below Phosphorous - so in a sense, this is a bit like the much more exciting Carbon -> Silicon change which might get you talking rocks on lava worlds breathing vaporized sand and other badass shit. But it's only a tiny bit similar to that, because the role that Phosphorous plays in biology is much different than that of Carbon. Carbon is what everything is made-out-of, Phosphorous is stuck onto the ends of things in order to provide high-energy bonds which can be exploited as an energy currency.

          I would bet that this organism does this as a defense against viruses - which, generally speaking, will not have arsenic-DNA or arsenic-RNA, and so would not be able to infect this organism.
        • by Mindcontrolled (1388007) on Thursday December 02, 2010 @04:25PM (#34422322)
          From a biochemist's point of view, this is a huge substitution, as phosphate and arsenate compounds do usually not coexist well in organisms, hence the toxicity of arsenic. While "everything is made out of carbon", carbon is the rather boring compound that gives stuff its structure. High-energy-bonds, like formed by certain phosphate compounds, give stuff the energy to actually DO things. The virus defense theory is way off, btw - this bacterium evolved in a high-arsenic environment, so this is way more likely a way to cope with the chemical composition of its evolutionary niche.
        • by Defenestrar (1773808) on Thursday December 02, 2010 @04:56PM (#34422730)
          Sounds good except for the fact that you're forgetting that arsenate is more reactive than phosphate which means the arsenate based backbone of DNA should be constantly getting ripped to shreds. Either this bacteria has found a way to protect the backbone or it has a hyper effective repair mechanism. Either would be very worth learning about. (Immortality anyone)?
    • by arth1 (260657) on Thursday December 02, 2010 @04:06PM (#34421996) Homepage Journal

      It replaces MOST phosphorus atoms with arsenic, but not all.

      Correct. It replaces the rest with old lace.

    • by yincrash (854885) on Thursday December 02, 2010 @04:09PM (#34422076)
      To be very clear, Felisa (the primary paper author) stated during the Q&A that all they know for sure is that there is not enough phosphorus in the bacteria for it's biochemical processes and the only reasonable conclusion is that arsenic is taking it's place. Not enough analysis to know percentages of what is using what.
    • by pz (113803)

      It replaces MOST phosphorus atoms with arsenic, but not all.

      After listening to the conference, it appears they don't know if it actively replaces phosphorous with arsenic, or it's happily living that way already. The experiment (based on listening to the lead author talk about it, which should be good enough, and if it isn't, I blame the author) was that they took a dollop of Mono Lake mud and put it in a laboratory environment that was rich in everything except (a) it wholly lacked phosphorus (how did they eliminate the phosphorus from the mud?) and (b) it had a "

      • by Anonymous Coward

        What they did was take samples of bacteria from the mud, and placed them in three conditions. In one condition they kept raising the cells in normal, phosphorous containing substrate, removing a small portion to another phosphorous containing substrate, and repeating for generations. In another they put the cells on a substrate lacking phosphorous or arsenic, and removed a small portion to another empty substrate, and so on. Finally, they put some on a substrate containing phosphorous and arsenic, and ke

  • by RocketRabbit (830691) on Thursday December 02, 2010 @04:01PM (#34421900)

    NASA has really started to irritate me, with their latest few announcements. Rather than just issuing the data and having a little show about its implications in NASA TV, they first make an announcement that they will make an announcement, then for a few weeks there is rampant speculation (even though it's entirely probable that the data is ready) and finally they make their announcement in a media-circus style event.

    NASA should just make the damn announcements on their web site and on their TV channel, and let the science press (read: science tabloids) publish it as they will.

    If their current trend continues, pretty soon NASA will be announcing their announcement of their announcement of a press conference to announce their data. It's a waste of time and energy for everybody. I don't know about you, but I simply want my news, I don't want news that there will be news of note in the near future.

    • by arth1 (260657) on Thursday December 02, 2010 @04:07PM (#34422018) Homepage Journal

      NASA has really started to irritate me, with their latest few announcements. Rather than just issuing the data and having a little show about its implications in NASA TV, they first make an announcement that they will make an announcement, then for a few weeks there is rampant speculation (even though it's entirely probable that the data is ready) and finally they make their announcement in a media-circus style event.

      They probably hired a PR manager who used to work at Apple.

    • by blair1q (305137)

      It's PR, and it's cheap.

      It means someone will cover the event instead of the event being covered by anyone who happened to be sleeping in the press room when the event began.

      Not doing it this way is a gig against the past PR people.

    • by Amouth (879122)

      they need money.. this drums up PR.. makes people think about them.. puts their name in the spot light..

      keeping their name out there is about their only way to survive the long haul right now.. they way they have been treated the past decade.. if the public lost interest in them i'd bet they would disappear quickly.

    • First of all, exaggerate much? Where was this "few weeks" of "rampant speculation"? The first I knew of this was NASA announcing 3 days ago that there would be a conference:
      http://www.nasa.gov/home/hqnews/2010/nov/HQ_M10-167_Astrobiology.html [nasa.gov]

      Besides that, come on....here is this young scientist at the very start of her career (she received her PhD in 2006) and she makes what is (in the scientific community) a pretty earth shattering discovery. Did you watch the video on NASA? I did...this lady is full of ex

  • by Confusedent (1913038) on Thursday December 02, 2010 @04:02PM (#34421908)
    It wasn't phosphorus free, in fact they hadn't confirmed how much of the phosphorus had been substituted with arsenic, but they did mentioned it was not 100%. They also mentioned it was more than just DNA (ATP was also mentioned, although they implied more).
    • It wasn't phosphorus free, in fact they hadn't confirmed how much of the phosphorus had been substituted with arsenic, but they did mentioned it was not 100%. They also mentioned it was more than just DNA (ATP was also mentioned, although they implied more).

      In one way, if you replace the P in DNA with As, you get ATP -- well, we should be calling it ATAs, shouldn't we? -- for free, since the adenosine in ATP is derived from the adenine in DNA: adenosine is adenine attached to a ribose, while the base in DNA is adenine attached to a ribose missing one oxygen, hence the "deoxyribo" part of deoxyribonucleic acid.

      But with that said, the chemistry of a triarsenate should be significantly different than the chemistry of a triphosphate, so that's more surprising to

  • real info (Score:5, Informative)

    by burris (122191) on Thursday December 02, 2010 @04:02PM (#34421928)

    According to this NYT article [nytimes.com] this is a normal earthly bacterium that, when placed in an environment full of arsenic, started swapping arsenic for phosphorus. It's not a totally new form of life unrelated to what we know.

    • Re: (Score:2, Funny)

      I want my money back!!!
    • Re:real info (Score:5, Informative)

      by blair1q (305137) on Thursday December 02, 2010 @04:17PM (#34422194) Journal

      But it sort of is.

      We've always ignored the chances of life on extraterrestrial bodies with significant levels of arsenic on the empirically founded theory that arsenic doesn't work in place of phosporus in living systems.

      So while this is a lifeform we already knew about, it's a different form of life from what we understood.

      The question remains, is it possible for DNA to have evolved in an environment rich in arsenic, or would it have had to evolve in an arsenic-free environment, and just happen to have enough integrity once it's formed to tolerate the replacement of phosphorus atoms with arsenic atoms?

  • by JamesP (688957) on Thursday December 02, 2010 @04:05PM (#34421980)

    How I am supposed to poison the darn thing now??!?!

  • by commisaro (1007549) on Thursday December 02, 2010 @04:05PM (#34421986) Homepage
    The Gizmodo article, like most of the speculation, was largely overblown:

    NASA has discovered a completely new life form that doesn't share the biological building blocks of anything currently living in planet Earth, using arsenic to build its DNA, RNA, proteins, and cell membranes. This changes everything.

    That is not the case. The DNA is largely the same, except that phosphorous has been exchanged with Arsenic. Don't get me wrong, this is still a hugely interesting discovery, but it was implied during the pre-conference speculation that this was an entirely separate instance of abiogenesis, and that is simply not the case, unfortunately.

    • by TimmyDee (713324)

      Somehow I'm not surprised. As a gadget blogger, he got in waaaay over his head by speculating about a microbiology discovery.

      In other words, typical Gizmodo/Gawker.

  • I recall one of the arguments against panspermia, the origin of life from space and particularly molecular clouds, was a lack of phosphorus (a lithophile). Interesting that phosphorus deficit is part of this experiment.
  • Can someone post a link to something explaining the significance of the discovery for the layperson?

    • It is more evidence to support the hypothesis that life could be made from different elements than the ones that life as we know it are made from. Your DNA, like most living organisms' DNA, is made from five elements: hydrogen, carbon, nitrogen, oxygen, and phosphorus. This is evidence that DNA could be made using arsenic instead of phosphorus, which has similar chemical properties.

      Personally, I think it would have been more exciting if they had discovered silicon based life, which would be a life for
    • by blair1q (305137)

      There is none.

      Scientists will ask for grant money based on expanding the search for life in outer space.

      It will keep a few scientists employed, and maybe in the future we'll be able to do something with the information we learn from their research.

      Nothing of value will come of it for any currently living layperson who does not see the value in science as an intellectual pursuit.

  • by digitaldc (879047) * on Thursday December 02, 2010 @04:08PM (#34422044)
    The discovery of this microorganism that can use arsenic to build its cellular components may indicate that life can form in the absence of large amounts of available phosphorus, thus increasing the probability of finding life elsewhere in the universe. The find gives weight to the long-standing idea that life on other planets may have a radically different chemical makeup and may help in hunt for alien life. [wikipedia.org]

    The more we think we know about, the greater the unknown... -Neil Peart
    • by blair1q (305137)

      Yup. The Arsenide-based-Phosphorus lifeforms will be found sitting on a rock next to the Silicon-based lifeforms.

  • Wolfe-Simon's team took mud containing bacteria from the arsenic-rich Mono Lake and grew them in ever decreasing concentrations of phosphorous. Their rationale was that since arsenic is just below phosphorous in the periodic table, and shares many of its chemical properties and is even used as a source of energy for some bacteria, the bugs would be able to swap one for the other. That is just what happened.

    From the New Scientist article. While it's possible, it hasn't been found in nature. The article also mentions why it might be unlikely. http://www.newscientist.com/article/dn19805-arseniceating-bacteria-point-to-new-life-forms.html [newscientist.com]

    .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.

  • by Trip6 (1184883)

    We're doing terrestrial-based bio experiments now? Shouldn't this be left to Con-Agra in an effort to find tastier corn?

  • And I for one welcome our new GFAJ-1 overlords. Whatever. Here's a link to the Wikipedia article. http://en.wikipedia.org/wiki/GFAJ-1 [wikipedia.org]
  • The bacterium GFAJ-1 is a strain of the Halomonadaceae family which is a http://en.wikipedia.org/wiki/Proteobacteria [wikipedia.org]. It's just somehow adapted to the use Arsenic in place of phosphorous on it's DNA.

    No ET. No shadow biosphere. But it pushes the envelope of where life can possibly exist and demonstrates that life could function, possibly evolve in an aresnic-rich phosphorous-poor environment. Importantly it shows there isn't some exact balance of elements necessary to support life, you can swap out element
  • w00t! now that the whole life on other planets question has been answered, can we please start colonizing mars?

  • See, this is why I hate slashdot.

    Instead of telling us 'Gizmodo was right', like we all read Gizmodo and keep constantly up to date about what's going on over there, how about TELLING US THE ACTUAL THING THAT HAPPENED.

    No, I shouldn't have to follow a link to figure it...there's supposed to be an 'article summary', which, you know, gives some hint as to what happened.

    Instead of just saying 'Oh, hey, these other people were right in their guess about a thing which i won't mention that they thought NASA would say.'. Well, woo-fucking-hoo. I'm sure we were all on the edge of our seat betting in the 'How correct is Gizmodo?' pool, and they just got a point! Wow! Who cares about actual news events, let's all sit there and count Gizmodo's points, or something.

    Timothy, you goddamn fucking moron. It's one thing when the article summary is misleading or just flat out incorrect, but slashdot has now managed to hit a new low where the article summary doesn't even exist.

  • by MaWeiTao (908546) on Thursday December 02, 2010 @05:04PM (#34422850)

    Very interesting, but I get the impression that NASA is merely trying to demonstrate to the public why they're important and why they deserve our tax dollars. Not that they need convincing me, but they've got a lot of competition for tax money right now.

    I just read that the House passed a $4.5 billion child nutrition bill apparently intended to promote better eating habits. $4.5 billion for the government to do something kids will ignore and parents should be responsible for anyway. And in the meantime NASA gets screwed.

  • by Danathar (267989) on Thursday December 02, 2010 @05:29PM (#34423236) Journal

    I captured and converted it to mp4 format for anybody that wants to view it.

    http://www.wuala.com/danathar/public [wuala.com]

    file is nasa.mp4 (it's the only one on that page)

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