Redefining Life - Bacteria Found That Reproduces Using Arsenic

  • metta

    Posts: 39075

    Dec 03, 2010 2:43 AM GMT
    Life Built With Toxic Chemical: First Known Microbe on Earth Able to Thrive and Reproduce Using Arsenic

    arsenic-microbes-life-mono-lake_29775_60


    http://www.sciencedaily.com/releases/2010/12/101202140622.htm


    Bacteria munch on arsenic, redefining life


    http://www.mercurynews.com/san-mateo-county/ci_16763468



    http://news.nationalgeographic.com/news/2010/12/101202-nasa-announcement-arsenic-life-mono-lake-science-space/
  • Posted by a hidden member.
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    Dec 03, 2010 2:50 AM GMT
    This is cool!

    It was the final story on NBC Nightly News tonight. You know...NBC: National Bastion of COMMUNISM!!!!!!!!!


    BTW...Is this one of those threads that conservativejock was menstruating about earlier?
  • Sk8Tex

    Posts: 738

    Dec 03, 2010 5:21 AM GMT
    Aww you beat me to it again lol... I saw this while at work and was fascinated by it. Kinda forces you to rethink what planets would be capable of supporting life.
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    Dec 03, 2010 5:31 AM GMT
    They found my great great great grandparents?!!! icon_lol.gificon_cool.gif
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    Dec 03, 2010 5:42 AM GMT
    This should really have been a no brainer. Lifer will form and thrive given any number of conditions. As long as a few basics are met it's possible to start anywhere.
  • BIG_N_TALL

    Posts: 2190

    Dec 03, 2010 5:54 AM GMT
    This is soooooo cool. It reminds me of my microbiology days icon_cool.gif
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    Dec 03, 2010 6:47 AM GMT
    Just like the Xmen movie, we are evolving! At least the bacteria are.
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    Dec 03, 2010 11:15 AM GMT
    Actually I was expecting something about selenium (which can replace sulfur and I've actually grown bacteria in the lab using selenium)...but arsenic replacing phosphorus is cool too.

    So much for interspecies sex (since your potential partner is toxic to you)...icon_twisted.gif
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    Dec 03, 2010 12:35 PM GMT
    i always love you posts, metta. you always manage to open my eyes just a little wider each time. it's refreshing. thank you for sharing.
  • Kage

    Posts: 707

    Dec 03, 2010 12:36 PM GMT
    I love extremophiles.
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    Dec 03, 2010 1:07 PM GMT
    q1w2e3 saidActually I was expecting something about selenium (which can replace sulfur and I've actually grown bacteria in the lab using selenium)...but arsenic replacing phosphorus is cool too.

    So much for interspecies sex (since your potential partner is toxic to you)...icon_twisted.gif


    To be perfectly honest phosphate -> arsenic is a lot cooler than sulphur -> selenium. Phosphate is such an integral part of biology as energi carriers, heritability, and functional structures. Think about it, phosphate is actually part of the backbone in tRNAs and the rRNA of ribosomes. And that has to still fold correctly but with arsenates instead of phosphates. And all the ATP, GTP, and creatine-monophosphate would have to run on ATA, GTA, and creatine-monoarsenate (actually: do bacteria use creatine-monophosphate?).
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    Dec 03, 2010 4:19 PM GMT
    I can't wait to find a silicon based lifeform in place of carbon or cesium replacing potassium or sodium.icon_eek.gif
    anyway, if you read the paper, there's no evidence that arsenic took the role of phosphate in DNA or RNA and there was still phosphate in the medium. So much for the hype.

    http://www.huffingtonpost.com/athena-andreadis-phd/arsenic-and-odd-lace_b_791454.htmlThe tables in the Science paper are eloquent on how reluctant even hardy extremophiles are to use As instead of P. Under normal growth conditions, the As: P ratio in their biomass was 1:500. When P was rigorously excluded and As had been raised to three times the level in lake Mono, the As: P ratio remained at a measly 7:1. Furthermore, upon fractionation As segregated almost entirely into the organic phase. Very little was in the aqueous phase that contains the nucleic acids. This means that under extreme pressure the bacteria will harbor intracellular As, but they will do their utmost to exclude it from the vital chains of the genetic material.
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    Dec 04, 2010 10:26 AM GMT
    rats, I made the thread too late icon_sad.gif
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    Dec 04, 2010 10:26 AM GMT
    http://www.realjock.com/gayforums/1263175
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    Dec 04, 2010 10:28 AM GMT
    q1w2e3 saidI can't wait to find a silicon based lifeform in place of carbon or cesium replacing potassium or sodium.


    Hmm how about chlorine replacing oxygen??
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    Dec 04, 2010 10:39 AM GMT
    q1w2e3 said
    anyway, if you read the paper, there's no evidence that arsenic took the role of phosphate in DNA or RNA and there was still phosphate in the medium. So much for the hype.


    Hmm, thats not what this one here said:

    "Rather than just retaining arsenic inside the cells, the authors provided evidence that the bacteria actually integrated arsenic into DNA and possibly other biomolecules. They found higher arsenic and lower phosphorus content in purified genomic DNA of bacteria grown in arsenate compared to control cells. "

    http://arstechnica.com/science/news/2010/12/bacteria-can-integrate-arsenic-into-its-dna-and-proteins.ars
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    Dec 04, 2010 11:47 AM GMT
    http://www.wired.com/wiredscience/2010/12/nasa-finds-arsenic-life-form/“Every organism that we know of uses ATP and phosphorylated DNA,” says biogeochemist Matthew Pasek of the University of South Florida in Tampa. He says the new research is both fascinating and fantastic. So fantastic, that a lot of work is needed to conclusively show exactly how the microbe is using arsenate.

    Both phosphate and arsenate can clump up into groups, and with their slightly negative electric charge, slightly positive DNA would be attracted to such clumps, says Pasek. Perhaps the arsenic detected in the DNA fraction was actually a nearby clump that the DNA wrapped itself around, he speculates.


    Also, what remains to be determined is whether arsenate is in the DNA backbone or just an adduct.

    And please read the quote from above where she says:
    author who wrote on Star Trek-like theoretical artificial life formsFurthermore, upon fractionation As segregated almost entirely into the organic phase. Very little was in the aqueous phase that contains the nucleic acids. This means that under extreme pressure the bacteria will harbor intracellular As, but they will do their utmost to exclude it from the vital chains of the genetic material.


    Also not mentioned are the vacuoles that the bacteria had after exposure to arsenic--might indicate that arsenic was actively extruded and isolated rather than being used preferentially inside the cell.

    http://www.wired.com/wiredscience/2010/12/nasa-finds-arsenic-life-form/But Shock says the real value of the work isn’t in the specifics. “This introduces the possibility that there can be a substitution for one of the major elements of life,” he says. Such research “stretches the perspective. Now we’ll have to see how far this can go.”

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    Dec 04, 2010 2:22 PM GMT
    q1w2e3 said

    Also, what remains to be determined is whether arsenate is in the DNA backbone or just an adduct.


    I agree with everything you say except with the question of whether it can be an adduct... unless they are lying in this article, the phosphor content was lower in the purified DNA genome... indicating that the phosphorus must have been replaced by something else, Ill be darned if thats not the arsenic
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    Dec 04, 2010 2:27 PM GMT
    amar_m saidq1w2e3 said

    Also, what remains to be determined is whether arsenate is in the DNA backbone or just an adduct.


    I agree with everything you say except with the question of whether it can be an adduct... unless they are lying in this article, the phosphor content was lower in the purified DNA genome... indicating that the phosphorus must have been replaced by something else, Ill be darned if thats not the arsenic


    Yes, but if, for example, it something like arsenic instead of phosphor in membrane phospholipides, it becomes a lot less glamourous than arsenic based DNA
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    Dec 04, 2010 2:31 PM GMT
    minox said
    amar_m saidq1w2e3 said

    Also, what remains to be determined is whether arsenate is in the DNA backbone or just an adduct.


    I agree with everything you say except with the question of whether it can be an adduct... unless they are lying in this article, the phosphor content was lower in the purified DNA genome... indicating that the phosphorus must have been replaced by something else, Ill be darned if thats not the arsenic


    Yes, but if, for example, it something like arsenic instead of phosphor in membrane phospholipides, it becomes a lot less glamourous than arsenic based DNA


    Absolutely, they stated it was in the purified DNA genome however in this article... other articles have stated otherwise though.. we'll see
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    Dec 04, 2010 7:10 PM GMT
    If you read the methods section (which is free on sciencemag.org), they use a standard chloroform/phenol/aqueous extract of DNA, then run them on a gel after digestion. A form of mass spectrometry is then used. (They also had a radioactive form of As used in another experiment)

    So yes, they proved that As was somehow incorporated into the DNA at very small amounts, compared to phosphate. The question that remains is whether
    1. It's in the backbone (i.e. replacing phos in the deoxyribose-phos-deoxyribose backbone)
    2. or it's incorporated elsewhere in the DNA (i.e. not in the backbone)

    DNA adducts are covalently bonded chemicals to DNA, e.g. cisplatin. So a remote possibility is that As is in a DNA adduct like platinum, and it would be wrong to say that As is replacing P.

    Structural studies are needed of the extracted DNA.

    http://en.wikipedia.org/wiki/DNA_adducts

    http://www.sciencemag.org/content/suppl/2010/12/01/science.1197258.DC1/Wolfe-Simon-SOM.pdf
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    Dec 04, 2010 8:59 PM GMT
    Gah! That's so fucking boring... sounds like just another ion extremophile.

    To be honest I can easily imagine extraterrestrial life without phosphorus or sulphur. There are things like synthetic PNA which hybridizes with DNA but is without phosphorus. I have a hard time with the idea of replacing carbon with silicium tho. On the other hand, infinite universe, etc.
    I am very keen on the idea of a world very rich in fluoride and life based on a triple phase system, i.e. hydrophilic, lipophilic, and fluophilic.