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NASA Confirms Discovery of Organism With Phosphorus-Free DNA

Posted by timothy on 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."

22 of 380 comments (clear)

  1. First post (hopefully) by Anonymous Coward · · Score: 5, Funny

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

  2. Neat, but... by mikaelwbergene · · Score: 5, Insightful

    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.

    1. Re:Neat, but... by albeit+unknown · · Score: 5, Funny

      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!

    2. Re:Neat, but... by Bob9113 · · Score: 5, Funny

      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?

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    3. Re:Neat, but... by JustOK · · Score: 5, Funny

      it's Presidents all the way down.

      --
      rewriting history since 2109
    4. Re:Neat, but... by c6gunner · · Score: 5, Informative

      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.

  3. Not Phosphorus-Free by Elder+Entropist · · Score: 5, Informative

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

    1. Re:Not Phosphorus-Free by arth1 · · Score: 5, Funny

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

      Correct. It replaces the rest with old lace.

    2. Re:Not Phosphorus-Free by jfengel · · Score: 5, Insightful

      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.

    3. Re:Not Phosphorus-Free by sam_handelman · · Score: 5, Insightful

      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.

      --
      The good and new comes from no quarter where it is looked for, and is always something different from what is expected.
    4. Re:Not Phosphorus-Free by Mindcontrolled · · Score: 5, Informative

      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.

      --
      Ubi solitudinem faciunt, pacem appellant.
    5. Re:Not Phosphorus-Free by ColdWetDog · · Score: 5, Informative

      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.

      --
      Faster! Faster! Faster would be better!
    6. Re:Not Phosphorus-Free by Mindcontrolled · · Score: 5, Funny

      Man, don't you see? They got poison for holding together their DNA. That's not just a trick of Satan, that's Satan's own DNA! The Enemy is growing his spawn right there in California (not that anyone would be surprised by that). The end is near! Repent! Bible-based science - it works, bitches!

      --
      Ubi solitudinem faciunt, pacem appellant.
  4. real info by burris · · Score: 5, Informative

    According to this NYT article 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.

  5. Obligatory question by JamesP · · Score: 5, Funny

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

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  6. Gizmodo was not right by commisaro · · Score: 5, Informative
    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.

  7. Re:Announce an Announcement... by arth1 · · Score: 5, Insightful

    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.

  8. Arsenic and Old GFA-J1 by digitaldc · · Score: 5, Insightful

    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.

    The more we think we know about, the greater the unknown... -Neil Peart

    --
    He who knows best knows how little he knows. - Thomas Jefferson
  9. Re:News flash: NASA discoveres there's life on ear by Defenestrar · · Score: 5, Informative

    My thoughts are as follows:

    THIS IS BLOODY AMAZING! followed by a little more tempered cogitation:

    Arsenate is a triprotic species just like phosphate, each has a valence of +5, and it's directly one period down on the table so available electron shells in ground state will appear very similar. However arsenic possesses filled d orbitals and is about 7% less electronegative than phosphorous - these factors, among others, tend to make arsenate a little more reactive than phosphate which would make it less stable as a backbone of DNA. So if the degree of replacement is as thorough as NASA claims (they said they cultured it with zero phosphorous present - so only trace impurities) the cell has either found a way to strengthen the backbone or has developed an amazing repair mechanism which can deal with frequent DNA damage.

    NASA has two summaries here and here.

    Astrobiology has an article here.

    And http://www.sciencemag.org/">Science will release a paper later today.

  10. MORONS POSTING ARTICLES WITH NO INFORMATION by DavidTC · · Score: 5, Informative

    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.

    --
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  11. Re:First life form! by jitterman · · Score: 5, Funny

    I wonder if they found the Old Lace component yet.

    --
    For conscience is the wound, and there's naught to staunch it
  12. Re:News flash: NASA discoveres there's life on ear by somersault · · Score: 5, Insightful

    Similar things were thought about phosphate groups. Unfortunately, we were wrong.

    Unfortunate? I don't think it's unfortunate at all. It's things like this that make us question our "universal truths" that makes science so interesting and worthwhile.

    If we already knew everything there would be no need for science. We may "know a lot", but there's not a shortage of new things to learn.

    I don't necessarily think you're wrong about the carbon and hydrogen thing - I've only really studied a little physics and chemistry, no biology. But I do think you need to be more open to being wrong - and to see it as an opportunity to grow rather than as a slap in the face.

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    which is totally what she said