NASA's Big Astrobiology Discovery

[AndroidAR]

After much speculation, NASA, in a press conference, revealed the piece of research that they had hinted at: a microbe that thrives in arsenic, replacing phosphorus with the toxic element.

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

Ok, so it's not the "life on Titan" announcement that everyone was hoping for, but this is a big discovery, since in all other known life forms, arsenic disrupts the metabolic pathways, because it is chemically similar to phosphorus. So instead of the usual Carbon, Nitrogen, Hydrogen, Sulfur, Oxygen and Phosphorus found in all other life forms, its 6 basic chemicals are CHONAS rather than CHONPS I remember learning back in basic biology courses.

Its DNA and RNA must be heavy, since arsenic is twice as heavy as phosphorus.

 

[MRaverz]

For those wanting to know more, I found this article really helpful: http://blogs.discovermagazine.com/notrocketscience/2010/12/02/mono-lake-bacteria-build-their-dna-using-arsenic-and-no-this-isnt-about-aliens/

 

[borrofburi]

Ok, so it's not the "life on Titan" announcement that everyone was hoping for

It's certainly not the "sentient aliens have been visiting our planet" announcement mirandansa implied: http://forums.leagueofreason.org.uk/viewtopic.php?p=93242#p93242

 

[Anachronous Rex]

I have to admit that I'm just a tad disappointed.

Not that this isn't really great or anything, no no no. It's just that, when I first read the opening paragraph, I had a brief glimmer of hope that NASA had discovered a form of life that had either undergone abiogenisis (abiogenisized?) independently, or was at least a very early derivation from more common terrestrial life.

But no, it looks like this has evolved recently.

 

[Krazyskooter]

Yeah, I'm disappointed a bit too. I thought everyone who understood evolution would have figured that life would find a way to do this kind of thing.

 

[Kaliren]

Note: What follows is speculation :idea:

I think this is a hyped-up 'proof of concept' for NASA. A major reason for the Cassini mission to continue to operate is the possibility of life in the Saturn system, particularly on the moons Titan and Enceladus. Both moons have liquid, though they are much colder than earth. "Where there is liquid, there might be life' is a common speculation. I think NASA wants to prove that life can be chemically different than what we have on earth - that life can occur in very extreme conditions.

The drama in this announcement, is, I think, about preserving their funding. The new Congress is blathering on about fiscal austerity, and NASA wants something to prove their value. Finding life on other worlds is very appealing.

NASA's Cassini site http://saturn.jpl.nasa.gov/

It is part of NASA's mission to study the earth - http://earthobservatory.nasa.gov/ , so even though this new life was discovered on earth, it does fall under their purview.

 

[australopithecus]

So will there be a genome mapping sometime soon? I'm quite interested to find out when this species deviated from the normal DNA/RNA jigsaw puzzle and where it's ancestry lies.

 

[AndroidAR]

So will there be a genome mapping sometime soon? I'm quite interested to find out when this species deviated from the normal DNA/RNA jigsaw puzzle and where it's ancestry lies.

I would assume so, though it might be difficult because their DNA/RNA uses an arsenic backbone, rather than the phosphoric backbone common to other forms of life, and since arsenic is more than twice as heavy as phosphorus. However, I figure that they would just introduce it to a phosphorus-rich environment, and it would replace the arsenic with phosphorus and then sequence it from there.

It's classified as a Gammaproteobacteria, which includes a lot of pathogens like Salmonella and E. coli.

http://en.wikipedia.org/wiki/GFAJ-1

 

[australopithecus]

http://xkcd.com/829/

 

[Case]

Bacteria that are innately toxic. Brilliant. Ironic question: do these things need arsenic to survive?

 

[Anachronous Rex]

Bacteria that are innately toxic. Brilliant. Ironic question: do these things need arsenic to survive?

This was the first thing that struck me as well. What a wonderful defense mechanism. One wonders why they haven't spread elsewhere.

Also, XKCD, you slay me.

 

[borrofburi]

Bacteria that are innately toxic. Brilliant. Ironic question: do these things need arsenic to survive?

No. They don't even like arsenic, they're just able to cope with it barely and sometimes use it instead of phosphorous.

 

[Kaliren]

PZ Myers has a great analysis-
http://scienceblogs.com/pharyngula/2010/12/its_not_an_arsenic-based_life.php

 

[Deleted member 619]

If anybody's interested, I have acquired the paper by Wolfe-Simon et al. PM me your e-mither address if you want a copy.

 

[televator]

Watching the outcome of scientific scrutiny will be interesting.... Here's video of the announcement:

http://www.youtube.com/watch?v=JVSJLUIQrA0&feature=related

Sorry, I couldn't embed the vid. It had a strange URL.

 

[Deleted member 619]

Watching the outcome of scientific scrutiny will be interesting.... Here's video of the announcement:



Sorry, I couldn't embed the vid. It had a strange URL.

FIFY

You need to remove the extraneous bits and bobs, so:

[media=youtube]http://www.youtube.com/watch?v=JVSJLUIQrA0&feature=related[/media]

Needs to be:

[media=youtube]JVSJLUIQrA0[/media]