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← [UPDATE] - NASA-Funded Research Discovers Life Built With Toxic Chemical

[UPDATE] - NASA-Funded Research Discovers Life Built With Toxic Chemical - Comments

TheCroatianGuy's Avatar Comment 1 by TheCroatianGuy

Just watching the stream...go science!:D But arsenic? Damn. Just waiting for them to announce that there are beings with acid for blood and that we are all screwed!:P ;)

Thu, 02 Dec 2010 19:28:59 UTC | #557419

afascina's Avatar Comment 2 by afascina

I´m curious to know what would "Lenski" think about this notice from nasa.

Go evolution, go!

Regards from Brazil! =)

Thu, 02 Dec 2010 19:39:30 UTC | #557426

AtheistEgbert's Avatar Comment 3 by AtheistEgbert

What interests me is where in the evolutionary timescale this organism appeared. Whether it evolved to replace phosphorus with arsenic, or it's completely formed in this unique environment. It appears that the scientists were cautionarily saying 'substitution' rather than new life forming.

Substitution is nowhere near as exciting as new life forming.

Thu, 02 Dec 2010 19:44:11 UTC | #557430

mole at the counter's Avatar Comment 4 by mole at the counter

"As we pursue our efforts to seek signs of life in the solar system, we have to think more broadly, more diversely and consider life as we do not know it. Either that or visit Kentucky."

Thu, 02 Dec 2010 19:49:25 UTC | #557432

Neodarwinian's Avatar Comment 5 by Neodarwinian

Same family as phosphorous, but twice as massive. Wonder what a arsenic-sugar backbone to nucleotides would look like. Arsenic triphosphate? Arseolipids?

Thu, 02 Dec 2010 19:51:04 UTC | #557436

Philoctetes                                        's Avatar Comment 6 by Philoctetes

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

Thu, 02 Dec 2010 20:10:10 UTC | #557444

xocgx's Avatar Comment 7 by xocgx

AtheistEgbert, I'm with you...I am not familiar with the place they found this, but I'm wondering how long this life has been there for. Longer than humans, but we just never found it, or is this something that formed somewhat recently?

Thu, 02 Dec 2010 20:14:35 UTC | #557445

Stafford Gordon's Avatar Comment 8 by Stafford Gordon

If true, this is absolutely amazing; that Charlie Darwin really started something!

Thu, 02 Dec 2010 20:27:09 UTC | #557452

Cartomancer's Avatar Comment 9 by Cartomancer

I thought Margaret Thatcher was a form of arsenic-based life?

Thu, 02 Dec 2010 20:29:45 UTC | #557454

JuJu's Avatar Comment 10 by JuJu

Are they really saying that this is a new form of life not related to everything else on this planet. Does it belong to a separate family tree. It seems to me that the history of this lake makes it a perfect science experiment, since the freshwater tributaries where diverted from the lake some 50 years ago. If a certain bacteria living in the lake started dying off except for a lucky few that had particular mutations that enabled them to survive the chemical changes in the environment, then it seems logical that we would find the ones that survived. If this is what happened, then its just natural selection at work. Is anyone saying this bacteria is not related to all other life on earth, or are people just reading that into it. Life has a way of filling in the niches. This lake reminds me of Lenski's experiment. I'm not convinced that this is a separate form of life, but more of a new way life can survive. Although I'm open to the possibilities. I would like to hear Richards thoughts on this.

Thu, 02 Dec 2010 20:30:45 UTC | #557456

xocgx's Avatar Comment 11 by xocgx

Juju, ripped from the wiki entry:

On the tree of life, according to the results of 16S rRNA sequencing, the rod-shaped GFAJ-1 nestles in among other salt-loving bacteria in the family Halomonadaceae.[3]

Not that that answers much definitively, but that's something.

Thu, 02 Dec 2010 20:33:36 UTC | #557458

Neodarwinian's Avatar Comment 12 by Neodarwinian

http://www.wired.com/

Fuller article here.

Thu, 02 Dec 2010 20:40:41 UTC | #557465

Rikitiki13's Avatar Comment 13 by Rikitiki13

....so, the Toxic Avenger really could live?

Thu, 02 Dec 2010 21:02:44 UTC | #557485

AlexP's Avatar Comment 14 by AlexP

And here we have the most important difference between science and religion:

A new discovery is made, one that challenges our worldview, something that forces us to reconsider, to rethink what we knew, one that opens new possibilities and makes room for new theories...

And the scientists are excited. Instead of dismissing discoveries at odds with their dogma, to discard the new and unfamilier in favor of old traditions and laws, they embrace it, eager to learn, to understand, to expand their knowledge.

Thu, 02 Dec 2010 21:06:58 UTC | #557490

neil pharr's Avatar Comment 15 by neil pharr

It is not clear in this report if Arsenic is "substituted" in DNA other important molecules like ATP. Is the DNA normal, but with instuctions to use Arsenic instead of Phosphorus (where possible) when there is Phorsphorus missing in the environmnet.

Thu, 02 Dec 2010 21:07:11 UTC | #557491

Stafford Gordon's Avatar Comment 16 by Stafford Gordon

Cartomancer 9:

"Hell born hag" would have been my description; victim might have been another.

But, this isn't the place for the ad hominem, or perhaps ad "homifem". Personal opinions don't carry much weight here; leave that to the superstitious.

Sorry if I offend.

Thu, 02 Dec 2010 21:10:34 UTC | #557493

JuJu's Avatar Comment 17 by JuJu

I have the TV on in the background and just watched Michio Kaku on CNN tell everyone that we will have to rewrite all the biology text books. The way I see it is that we have to add some new information, not completely rewrite them. Heck, at one time on this planet no life breathed air into lungs. Now its common place, and we are still related to the life that didn't breath air into lungs. Now life has evolved to use arsenic as energy, and as far as I can tell its still related to the life that doesn't. As far as life on other planets go, I can imagine all kinds of life forms evolving to survive in all types of chemical soups and environments. Its still quite possible that life needs to start in a so called "goldilocks" zone. Then as planetary evolution takes place, life evolves to survive it. So, if we see planets that have certain chemical environments that some life on earth has evolved to survive in. That doesn't mean life could have started on that planet. At the same time if we find planets with chemical environments that life on earth can't survive, That doesn't mean life on that planet could not have evolved along with that planets changes to its current state.

EDIT= Michio Kaku was on msnbc.

Thu, 02 Dec 2010 21:13:34 UTC | #557495

A-Leprechaunist's Avatar Comment 18 by A-Leprechaunist

It's just God er... showing off... again...

Thu, 02 Dec 2010 21:13:36 UTC | #557496

The Plc's Avatar Comment 19 by The Plc

Comment 10 by JuJu :

I would like to hear Richards thoughts on this.

Hear hear.

Thu, 02 Dec 2010 21:17:51 UTC | #557499

God fearing Atheist's Avatar Comment 20 by God fearing Atheist

Fascinating.

I'm trying to read all I can by following links. Unfortunately the NASA server appears too busy. I wonder why? I hope I know the answer.

Thu, 02 Dec 2010 21:26:28 UTC | #557504

Steven Mading's Avatar Comment 21 by Steven Mading

If it's just putting arsenic in places phosphorous normally goes, that's not necessarily evidence of separately evolved life. That could be an adaptation of the normal life we're familiar with (or if this is older, the other way around). Now, if it turns out its replication mechanism was not based on DNA or RNA but instead looked totally different, then that would be evidence it's a separate independently evolved life. If it has something that is suspiciously similar to RNA and DNA in form and structure (but with phosphorous being replaced, of course), then I figure it's still a distant relative that belongs in the tree of life somewhere. It might very well be the most distantest of distant relatives, but it would still share a common origin in that case.

Thu, 02 Dec 2010 21:48:44 UTC | #557517

Richard L's Avatar Comment 22 by Richard L

Read the original science paper instead of speculating like this people... it's quite an easy read really (anything related to astrobiology is, because the field really tries to understand the fundamentals rather than some annoyingly complicated [usually aka: extremely important] detail).

If you feed arsenic to a certain kind of bacteria, even though arsenic is really reactive and will replace almost whatever phosphorus that comes in its path - thus altering the chemistry of the living organism - this one special bacteria can handle it and thrive. The main astrobiological lesson, of course, being that we know life is stranger than we thought before today [ahem, the day you read the paper/conducted the experiment - since this was known by some before today].

Anyway, that's the gist of the paper; arsenic can replace phosphorus in DNA.

Why (might be part of the paper, I didn't get that far before I had to go out for dinner)? Dunno - lets speculate:

1) life abiogenesized being able to use arsenic instead of phosphorus and most of it evolved away from there because arsenic is way to unstable? This is reasonable I think because the reactive arsenic being able to come back into living matter seems unnecessary so there would be evolutionary pressure to get rid of it.

2) some part of life became able to use arsenic because of some mutation allowing it to keep it together under new circumstances? Also reasonable, because if there's arsenic present in an environment, bacteria will be in contact with it daily - bacteria mutates rapidly because of the short generations and thus it might become able to handle some part of arsenic.

Disclaimer: I'm into astrobiology, but I'm more interested in the moons and planetary structures that would allow life (lakes, mud and stuff, aka "where do we look for life?"), rather than life itself. I barely understood the paper because my chemistry is basically only on high school level... So, if I understood it; you will!

Thu, 02 Dec 2010 21:51:37 UTC | #557520

healthphysicist's Avatar Comment 23 by healthphysicist

My understanding is that the P-->As took place in the lab.

It wasn't discovered in the lake to use As.

Its environment in the lab was manipulated and it incorporated As in that environment.

Thu, 02 Dec 2010 21:53:10 UTC | #557521

Gmork's Avatar Comment 24 by Gmork

Life is the invisible machinery. Whatever you put into it, something will come out if it fits, and arsenic fits. Isn't that all there is to it? I'm not so ingrained in the absolutes in biology, but the article mentioned this was predicted, so why the "oh my god, so unexpected" tone one usually expects to find in the absolutist minds of the religious? It is as if scientists were supposed to have made this absolutist claim about what life is. I'm not really surprised about anything, though, so I'm probably biased to start with.

I hope Michio Kaku didn't say that we have to rewrite the books. I guess he exaggerates a lot, being enthusiastic and all. It would be a dumb thing to say, though.

Thu, 02 Dec 2010 22:08:49 UTC | #557529

motieone's Avatar Comment 25 by motieone

Yes you are correct, the new form of life was not 'discovered' but instead 'created' the NASA article states

The newly discovered microbe, strain GFAJ-1, is a member of a common group of bacteria, the Gammaproteobacteria. In the laboratory, the researchers successfully grew microbes from the lake on a diet that was very lean on phosphorus, but included generous helpings of arsenic. When researchers removed the phosphorus and replaced it with arsenic the microbes continued to grow. Subsequent analyses indicated that the arsenic was being used to produce the building blocks of new GFAJ-1 cells.

From http://www.nasa.gov/topics/universe/features/astrobiology_toxic_chemical.html

Thu, 02 Dec 2010 22:14:47 UTC | #557534

SourTomatoSand's Avatar Comment 26 by SourTomatoSand

They found that a microbe can thrive on arsenic; this has never been found before, because even cells that breathe arsenic don't incorporate them into their DNA. This bacterium has. So what is amazing here is the implication that life may be able to get its start with chemicals that we used to think couldn't be used for life. However, creating life from nothing but toxic chemicals is NOT what has happened here-- the scientists in the study took existing bacteria and placed them in an environment filled with arsenic. Therefore, the arsenic-based bacteria are still related to all other life on Earth. The implication that we may have to look at a wider range of environments/planets/moons as candidates for abiogenesis is what is important here.

Thu, 02 Dec 2010 22:27:34 UTC | #557538

Alan4discussion's Avatar Comment 27 by Alan4discussion

The team chose to explore Mono Lake because of its unusual chemistry, especially its high salinity, high alkalinity, and high levels of arsenic.

.The lake has mineral pillars from dissolved salts and a very unusual eco-system. I think these quotes will clarify the position for some posters.

"We know that some microbes can breathe arsenic, but what we've found is a microbe doing something new -- building parts of itself out of arsenic,

The newly discovered microbe, strain GFAJ-1, is a member of a common group of bacteria, the Gammaproteobacteria. In the laboratory, the researchers successfully grew microbes from the lake on a diet that was very lean on phosphorus, but included generous helpings of arsenic. When researchers removed the phosphorus and replaced it with arsenic the microbes continued to grow.

This makes it clear that these bacteria are simply relatives of other bacteria, suggesting that this is an adaptation to the extreme conditions at this lake.

I have linked this short Mono Lake California, above and below water - video to give a background view of the lake its wild-life and its chemistry.

Thu, 02 Dec 2010 22:50:17 UTC | #557542

helen sotiriadis's Avatar Comment 28 by helen sotiriadis

here's a write up by pz myers.

it seems that bacteria has been coaxed into using arsenic, but not that it had developed independently.

Thu, 02 Dec 2010 23:17:00 UTC | #557550

AtheistEgbert's Avatar Comment 29 by AtheistEgbert

As PZ Myers says:

It's perfectly reasonable and interesting work in its own right, but it's not radical, it's not particularly surprising, and it's especially not extraterrestrial. It's the kind of thing that will get a sentence or three in biochemistry textbooks in the future.

The more I look into this, the more disappointed I am. It was already known that this was how arsenic behaved.

And he continues:

It doesn't say a lot about evolutionary history, I'm afraid. These are derived forms of bacteria that are adapting to artificially stringent environmental conditions, and they were found in a geologically young lake — so no, this is not the bacterium primeval.

Blah. Not a new life form.

Thu, 02 Dec 2010 23:30:32 UTC | #557558

Richard Dawkins's Avatar Comment 30 by Richard Dawkins

Are they really saying that this is a new form of life not related to everything else on this planet. Does it belong to a separate family tree?

You could be forgiven, given all the hype, for thinking this. But alas the answer is no. Absolutely and categorically not. If that were the case, the bacteria would have a different DNA code, or a completely different genetic system not involving DNA at all. If that were the case, this would be one of the most exciting biological discoveries ever made, for it would show that life had evolved more than once. We would have more than one example of the origin of life, and we would immediately have to revise, in an upward direction by many orders of magnitude, our estimate of the abundance of life in the universe.

The truth is hugely less earth-shattering, but still very interesting. Rather as Lenski did with different chemical insults, these researchers kept bacteria in an arsenic-rich environment and selected out a strain that could tolerate arsenic. They went on to show that the bacteria evolved the ability to substitute arsenic for phosphorus (the two elements are an octave apart in the periodic table, and share many properties, which is precisely why arsenic plays such a starring role in our murder stories: the body can't easily distinguish arsenic from vitally needed phosphorus and then discovers its mistake too late).

The researchers started with bacteria taken from lake Mono in California, which is heavily loaded with arsenic, and therefore there was reason to expect that bacteria in the lake might be more tolerant of arsenic than most organisms are. So it proved, and the researchers enhanced the effect by breeding bacteria in a phosphorus-deprived, arsenic-rich artificial environment. The artificially selected strain of bacteria were able to survive by replacing phosphorus with arsenic in many crucial molecules such as proteins and nucleic acids. This is a really interesting discovery, and it is a pity that the hype suggested something more, leading to an unfortunate sense of anti-climax when one reads the actual scientific paper.

So, this finding does not necessitate a major revision in our estimate of the ubiquity of life on other planets. It slightly increases that estimate, because it shows that life (our kind of life, DNA-based life) is chemically a bit more versatile than we had previously thought.

The paper in Science Express, by Wolfe-Simon et al, is unfortunately not lucidly written, and that is putting it kindly. Characteristically, PZ Myers, on Pharyngula, has a much clearer explanation.

Richard

Thu, 02 Dec 2010 23:37:46 UTC | #557562