Question of the Day, December 3, 2010

[GundamSentinel]

Though we've seen extremophiles all over the planet and personally I was kind of expecting something of the like, finding a life form based on entirely different chemistry is very neat. That said, NASA should be looking in space, not in lakes in California.

 

[GeorgW]

It is really quite awesome if you understand what it means. It was definitely more than I expected.

 

[Socken]

So they discovered a new life form on this planet? I don't see how that is exactly world shattering news.

It's not just a new life form, it's a new kind of life form. It functions on a fundamentally different level that was thought impossible up until now. This means that the assumption that all life has the same requirements is wrong. In fact it changes the very definition of life.

 

[TheTaco007]

I think it's pretty damn cool. I mean really, it lives on ARSENIC? Weird stuff...

This means that now hundreds if not thousands of planets previously thought inhabitable could potentially have life.

 

[6unn3r]

Ehhh ive found more interesting things growing in my fridge that might be considered "alien".

 

[Canadamus Prime]

So they discovered a new life form on this planet? I don't see how that is exactly world shattering news.

It's not just a new life form, it's a new kind of life form. It functions on a fundamentally different level that was thought impossible up until now. This means that the assumption that all life has the same requirements is wrong. In fact it changes the very definition of life.

What do you mean it has different requirements? It doesn't need to eat (in some form or other), breathe (in some form or other), and reproduce/propagate?

 

[Casual Shinji]

I'm sorry NASA, but bacteria ain't sexy.

Better luck next time.

 

[Socken]

So they discovered a new life form on this planet? I don't see how that is exactly world shattering news.

It's not just a new life form, it's a new kind of life form. It functions on a fundamentally different level that was thought impossible up until now. This means that the assumption that all life has the same requirements is wrong. In fact it changes the very definition of life.

What do you mean it has different requirements? It doesn't need to eat (in some form or other), breathe (in some form or other), and reproduce/propagate?

It's even more fundamental than that. I mean requirements as in elements present in order for life to be possible.

So far, all life ever discovered, from bacteria to plants to humans, was made up of carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur, so those were the elements that had to "be there" in order for it to be possible for living organisms to evolve (e. g. on other planets).

This bacteria however uses arsenic instead of phosphorous to hold its DNA together and activate proteins, among other things. Its basic chemical structure is different from any life form ever discovered. This means that there may potentially be life on planets that were previously deemed uninhabitable for lack of one or more of the basic elements.

 

[AudienceOfOne1]

As a budding biologist I can say that this is quite simply awesome!!!

 

[BENZOOKA]

I was absolutely sure they found an extra terrestial blancmange.

But that's cool as well. I wonder if that arsenic based life form wants to win the Wimbledon?

 

[Jingermanoo]

Technically this is an alien as it is so unfamiliar to use.
A key molecule for almost all biological reactions to occur is ATP with three phosphate molecules present in it. For these phosphate molecules to be entirely replaced with arsenate has overwhelming implications for the other potential lifeform differences.
Depending on the conditions, life as we know it could be created from a far greater scope of elements than the six that we used to believe comprised all living cells.

 

[Canadamus Prime]

So they discovered a new life form on this planet? I don't see how that is exactly world shattering news.

It's not just a new life form, it's a new kind of life form. It functions on a fundamentally different level that was thought impossible up until now. This means that the assumption that all life has the same requirements is wrong. In fact it changes the very definition of life.

What do you mean it has different requirements? It doesn't need to eat (in some form or other), breathe (in some form or other), and reproduce/propagate?

It's even more fundamental than that. I mean requirements as in elements present in order for life to be possible.

So far, all life ever discovered, from bacteria to plants to humans, was made up of carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur, so those were the elements that had to "be there" in order for it to be possible for living organisms to evolve (e. g. on other planets).

This bacteria however uses arsenic instead of phosphorous to hold its DNA together and activate proteins, among other things. Its basic chemical structure is different from any life form ever discovered. This means that there may potentially be life on planets that were previously deemed uninhabitable for lack of one or more of the basic elements.

I was never under the assumption that all life had to be carbon based. Granted, I'm no scientist, but I figured that, given the right conditions, life could develop anywhere and from anything. The remaining mystery is what sparks the creation of life under seemingly random conditions with seemingly random elements.

 

[psivamp]

Wait, I'm a little slow today. The big announcment was that they found some kind of arsenic based bacteria on earth in California?
Granted most, if not all life on earth is supposed to be carbon based that just seems underwhelming. If they discovered the bacteria in a sample of lunar or martian dirt from one of the probe/lunar landing missions then I'd be far more impressed.

It's still carbon-based. The replacement to carbon-based would be silicon-based -- which is theoretically possible just as replacing phosphorus with arsenic was theoretically possible. But, now, we have a living example of a creature using arsenic instead of phosphorus in it's DNA (instead of phosphate diester linkages between ribose sugars there are arsenate diester linkages) and instead of using adenine diphosphate and adenine triphosphate for cellular energy, these bacteria use adenine diarsenate and adenine triarsenate.

Basically, the possibilities for the existence of life does not rely on the element phosphorus and by the same token the theoretical possibility of life that is not carbon-based gains more plausibility.

If you look on the periodic table, arsenic is right below phosphorus and silicon is right below carbon. Arsenic and silicon weigh more than phosphorus and carbon respectively, but share many of the same chemical characteristics including possessing similar electronegativity and bonding behavior.

 

[psivamp]

*snip*

I was never under the assumption that all life had to be carbon based. Granted, I'm no scientist, but I figured that, given the right conditions, life could develop anywhere and from anything. The remaining mystery is what sparks the creation of life under seemingly random conditions with seemingly random elements.

Carbon typically forms four bonds. This allows it to form essentially infinite chains (polymers, including proteins). The most obvious alternative to carbon for the basis of complex life is silicon which has similar bonding characteristics although it would be less stable.

 

[anaphysik]

The implication that exolife might be radically different from terrestrial life is long overdue amongst some circles, and frankly, not that interesting.

But proof of radically-different biology, like what this research might show? That is completely awesome!

(I too was expecting just another extremophile (which is not to say that tardigrades aren't among my favourite animals, the cute little guys), but this gives new meaning to the term.)

 

[Canadamus Prime]

*snip*

I was never under the assumption that all life had to be carbon based. Granted, I'm no scientist, but I figured that, given the right conditions, life could develop anywhere and from anything. The remaining mystery is what sparks the creation of life under seemingly random conditions with seemingly random elements.

Carbon typically forms four bonds. This allows it to form essentially infinite chains (polymers, including proteins). The most obvious alternative to carbon for the basis of complex life is silicon which has similar bonding characteristics although it would be less stable.

Well the discovery of this new life form seems to support my theory, doesn't it.

 

[Jedoro]

Wake me up when we've found the Asari.

Or Twi'leks, whichever are found first.

 

[kitsunefather]

Like the Chernobyl Black Mushroom (uses gamma radiation to perform its photosynthesis functions from inside the cooling towers), this is another step in the notion of life existing in ways we thought impossible. But this..

Its replaced one of the basic building blocks of organic life with something else entirely. A heavy metal that is toxic to us and most advanced organisms. This.. this is monkeys doing algebra beautiful.

 

[RobCoxxy]

When NASA said they had some big news involving extraterrestrial life, I didn't think they'd have found it in a lake in California. I mean yes it's big and means there's more possibility of life in the universe, but anyone who's even thought about the maths behind life and star systems, planets, etc, knows there's likely to be millions of planets with life in our galaxy alone.

Set us up to knock us down, NASA.

Give me some ACTUAL extraterrestrial bacteria, galactic radio signals (another Wow signal please) or something actually extraterrestrial.

 

[DeadlyYellow]

It's important sure, but not as neat as a bacterial algae that turns water a rainbow of colors.