NASA Confirms Discovery of Organism With Phosphorus-Free DNA 380
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."
First post (hopefully) (Score:5, Funny)
It's life Jim, but not as we know it.
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http://en.wikipedia.org/wiki/The_Devil_in_the_Dark [wikipedia.org]
Neat, but... (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.
Re:Neat, but... (Score:5, Funny)
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.
Re:Neat, but... (Score:5, Funny)
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!
Re:Neat, but... (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?
Re:Neat, but... (Score:5, Funny)
it's Presidents all the way down.
Re:Neat, but... (Score:5, Insightful)
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)
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.
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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?
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A "web log" is the log kept by a web server. It may also mean something else to other people, but IMNSHO that meaning is incorrect when applied in the context of a web service. And also completely irrelevant to the point I made, which doesn't depend on whether you call slashdot a 'blog', a 'discussion board', a 'masturbation aid' or even 'cheese.'
The point is the
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It was probably Wait Wait Don't Tell Me
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Why do you think they call it freefall?
*scratches chin* Because they're Tom Petty fans?
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... 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.
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NASA's original release just said that this discovery "will impact the search for extraterrestrial life." Which CANNOT be interpreted as 'ZOMG WE FOUND ET!'
Sure it can!
"We found ET. So, uh, the search is over. Pretty big impact, right?"
First life form! (Score:2)
made of arsenic.
Re:First life form! (Score:5, Funny)
Someone get the Selenium! (Score:2)
Someone get a fire engine, some Selenium, and David Duchovney.
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Not Phosphorus-Free (Score:5, Informative)
It replaces MOST phosphorus atoms with arsenic, but not all.
Re:Not Phosphorus-Free (Score:4, Insightful)
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.)
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Yes.
Re:Not Phosphorus-Free (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.
Re:Not Phosphorus-Free (Score:4, Insightful)
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Re:Not Phosphorus-Free (Score:5, Informative)
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.
Re:Not Phosphorus-Free (Score:4, Interesting)
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.
Re:Not Phosphorus-Free (Score:5, Informative)
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.
Re:Not Phosphorus-Free (Score:4, Informative)
Re:Not Phosphorus-Free (Score:5, Funny)
Same tree of life.
Oh, you wacky evolutionists! Everyone knows that God doesn't mention this lifeform in Genesis, so it must be either (a) an analytical error, (b) a test of faith, or (c) a trick by Satan meant to deceive us. No proof of evolution here - move along...
Re:Not Phosphorus-Free (Score:5, Funny)
Re:Not Phosphorus-Free (Score:5, Funny)
Same tree of life.
So this is the microorganism that turns us into Pak protectors?
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Re:Not Phosphorus-Free (Score:5, Insightful)
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.
Re:Not Phosphorus-Free (Score:5, Informative)
Re:Not Phosphorus-Free (Score:5, Interesting)
Re:Not Phosphorus-Free (Score:5, Funny)
It replaces MOST phosphorus atoms with arsenic, but not all.
Correct. It replaces the rest with old lace.
Re:Not Phosphorus-Free (Score:5, Interesting)
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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 "
I just read the Science paper (Score:3, Informative)
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
Announce an Announcement... (Score:3, 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.
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.
Re:Announce an Announcement... (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.
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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.
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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.
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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
Not phosphorus free, not just DNA. (Score:4, Informative)
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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)
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.
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Re:real info (Score:5, Informative)
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?
Obligatory question (Score:5, Funny)
How I am supposed to poison the darn thing now??!?!
Re:Obligatory question (Score:5, Funny)
Shampoo?
Gizmodo was not right (Score:5, Informative)
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.
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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.
Panspermia (Score:2)
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Oops. There's a lack of arsenic there, too.
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I don't understand this (Score:2)
Can someone post a link to something explaining the significance of the discovery for the layperson?
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Personally, I think it would have been more exciting if they had discovered silicon based life, which would be a life for
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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.
Arsenic and Old GFA-J1 (Score:5, Insightful)
The more we think we know about, the greater the unknown... -Neil Peart
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Yup. The Arsenide-based-Phosphorus lifeforms will be found sitting on a rock next to the Silicon-based lifeforms.
Man made though, not naturally occuring (Score:2)
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.
NASA? (Score:2)
We're doing terrestrial-based bio experiments now? Shouldn't this be left to Con-Agra in an effort to find tastier corn?
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I don't know about you, but I'll keep my arsenic free corn.
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Wait. Corn could be tastier?
The species is named GFAJ-1 (Score:2)
It's still of this world. (Score:2)
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
time to colonize mars (Score:2)
w00t! now that the whole life on other planets question has been answered, can we please start colonizing mars?
MORONS POSTING ARTICLES WITH NO INFORMATION (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.
Money well spent. (Score:3)
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.
Link to Video of Press conference (Score:4, Informative)
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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Just like the discovery, it's a confirmation of something that's been previously discussed.
BAZINGA!
Re:First (Score:5, Funny)
I accept your apology.
Re:First (Score:5, Informative)
Actually, they DID discover a new life form. They [nasa.gov] didn't actually coax an existing bacteria to "use phosphorus". Instead, they discovered an existing organism that can use arsenic in its DNA and RNA rather than the phorphorus other life on earth uses.
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This is sure to shut up all those naysayers who accuse NASA of being a waste of resources...
Apparently they have a invested in a pretty good network though. I was surprised that the video stream didn't cut out at all considering that there could be tens of thousands if not more watching.
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Or, Yahoo did. Besides being listed as a sponsor on the NASA TV page [nasa.gov], if one looks at the Windows Media link (for instance) and examines the ASX file, one notes a reference to "http://playlist.yahoo.com/makeplaylist.dll?id=1369080&segment=149773". See for yourself [nasa.gov] (probably using wget).
Re:News flash: NASA discoveres there's life on ear (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 [nasa.gov] and here [nasa.gov].
Astrobiology has an article here [astrobio.net].
And http://www.sciencemag.org/ [slashdot.org]">Science will release a paper later today.
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'triprotic'??
What's that?
Watching porn on acid or something?
Re:News flash: NASA discoveres there's life on ear (Score:4, Interesting)
This link [purdue.edu] may help. If not (it is, after all, a link to the chemistry department of a university), this [wikipedia.org], this [wikipedia.org], or this [wikipedia.org] may.
And yes, since it has to do with DNA it is indeed porn on acid. Or maybe acid on porn.
Re:News flash: NASA discoveres there's life on ear (Score:4, Interesting)
Thanks for filling in the blanks. There's some things that I deal with so often that I forget I can sound a little weird when I get excited about science and open my mouth - phosphate is one of them.
But yeah - the short story is that phosphate (and arsenate) have three spots to kick hydrogen on or off with - and the number of hydrogens that hang out on a phosphate ion is very much related to the pH.
The long story (for anyone who cares) is that each of those hydrogens has a different equilibrium constant (pKa) at which it will pop off. H3PO4 is phosphoric acid but if you increase the amount of OH- in solution (or reduce the amount of H+) the first of those hydrogens will hook up with the OH- to make water which leaves H2PO4-. So the next hydrogen to take a hike will leave the phosphate at HPO4- - which means it's harder to leave and has a different pH (which is a fancy way of talking about the levels of H+ and OH- in water) it will hit equilibrium with. So on and so forth for each of the four phosphate species (0, -1, -2, -3 charge).
The really long version throws out concentration of the different species of phosphate and talks about activities, taking into account that the activity coefficient is affected by the square of the ion's charge... [We interrupt this chemistry lesson for the sake of sanity]
Strange - I forgot what I was talking about - but back to your question: yeah - DNA is both sex and acid
Re:News flash: NASA discoveres there's life on ear (Score:4, Interesting)
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
Hmmm. Maybe it methylates the DNA more? Or the histones are different. I guess - as you say - more repair enzymes is quite likely, since that just requires some promoter mutations.
The interesting question for me is whether any of the mechanisms are different for this organisms enzymes. For the last few months I've been sitting on the next desk to the maintainer of a database of biochemical mechanisms (MACiE - hi gemma, assuming you read slashdot, and happy birthday...) so maybe that's why it occurs to me. Many enzymes use ATP/NAD/other phosphate cofactors to make stuff, so if AsO4 has a slightly different chemistry, I wonder if different sidechains are used. Or, as I say, some completely different mechanisms (or pathways?).
Re:News flash: NASA discoveres there's life on ear (Score:4, Interesting)
Evidence of evolution? (Score:3)
DISCLAIMER - I am not an organic chemist. (although I did stay in a Holiday Inn Express last night)
Having watched the computer simulation, what I see is an organism that substitutes arsenic for phosphorus in all its internal chemistry.
Arsenic is similar enough to phosphorus, from a chemical standpoint, that the substitution works to form similar molecules - so DNA is still DNA, ATP is still ATP, etc.
In other words, this is still good old Terran life chemistry and life processes with a raw materiel switched
Holy crap! (Score:4, Interesting)
What if this microbe isn't "new" - what if it is old?
As in - what if life on Terra initially evolved based around an arsenic atom, and then later evolved to use the much better and more stable phosphorus?
DG
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I understand what you're saying here, but from everything we know (and we know a lot), the periodic table of elements is universal.
Some molecules (such as carbon or hydrogen) are simply so unique that they cannot be replaced by anything else. Nothing has the stability and bonding ability of carbon.
Similar things were thought about phosphate groups. Unfortunately, we were wrong.
The long and short of it is that no matter how hard you try, you'll never have an organism without hydrogen or carbon because there
Re:News flash: NASA discoveres there's life on ear (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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You seek certainty. That only exists in theory. In practice, we know the laws of physics are universal, for all practical purposes, for the reasons I mentioned. If that isn't good enough for you, stick with divinity school. Science is not for you.
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What does mine say??
Re:Hardly deserves the "New Life" headline.. (Score:4, Informative)
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With all that arsenic I doubt they will smell very good.
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since the general public will be goings "Arse-whaat"
No. That's what your mom said.
Re:Why all the fuss? (Score:5, Insightful)
because this confirms many unproven ideas that not all "life" is in the same form as we are a custom too - other than this.. all life that we knew before now on earth used the same base DNA structure..
basically they have found life.. not as we know it.. and means that some of our methods for proving there isn't life some place might be flawed.
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None whatsoever (guesswork is still guesswork).
If life evolved twice independently on earth I would think that life in the universe is quite common.
This news has nothing to do with independently evolved life, it's just an organism that has managed to substitute a similar element for one of the six elements used by all life on earth (including this bacterium, under regular conditions).
Most likely, life div evolve multi
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'Is this suggesting the bacteria might have piggybacked on an meteor? Could it have developed naturally on Earth?'
There's no particular evidence of an extra-terrestrial origin. It actually grows better when fed phosphate rather than arsenate, and the sequence of one of its ribosomal RNA genes places its pedigree in the known family tree of related organisms - see p7 of their supplementary data pdf (should be accessible to non-subscribers):
http://www.sciencemag.org/content/suppl/2010/12/01/science.1197258.DC [sciencemag.org]