Don't we already have this?...thought we called them...............................................politicians!?...
what a groundbreaking announcement. What a let down...I thought they were going to auction off the alien carcases from area 51 crash on ebay...
comorin From United States of America, joined May 2005, 4861 posts, RR: 16 Reply 10, posted (3 years 4 days 13 hours ago) and read 1988 times:
Actually, having cells that do not need phosphorus and substitute arsenic is a HUGE discovery as it blows away our understanding for the requirements for life. Imagine a life form that can evolve without the need for traditional elements - amazing. It opens up the possibilities of alternate life forms elsewhere.
I would like to issue an APB for DocLightning to come to our aid and explain.
oldeuropean From Germany, joined May 2005, 1992 posts, RR: 4 Reply 11, posted (3 years 4 days 13 hours ago) and read 1953 times:
Quoting comorin (Reply 10): Actually, having cells that do not need phosphorus and substitute arsenic is a HUGE discovery as it blows away our understanding for the requirements for life.
Yes, it's about this finding of bacteria in the Mono Lake. But some scientists already doubt the conclusions of Felisa Wolfe-Simon, because she hasn't proven yet, that these bacteria can live with arsenic instead of phosphorus (because it is a artificial condition produced in a labor) for a longer time.
connies4ever From Canada, joined Feb 2006, 4066 posts, RR: 13 Reply 12, posted (3 years 4 days 12 hours ago) and read 1911 times:
Quoting soon7x7 (Reply 3): I think NASA is going to try to prove that life really does exist on planet earth...Rubbish!
You must mean trying to prove intelligent life existing on Planet Earth.
Quoting comorin (Reply 10): Actually, having cells that do not need phosphorus and substitute arsenic is a HUGE discovery as it blows away our understanding for the requirements for life. Imagine a life form that can evolve without the need for traditional elements - amazing. It opens up the possibilities of alternate life forms elsewhere.
Actually, an alternate form of life based on silicon rather than carbon has been theorised for some time, and provided lots of fodder for sci-fi writers:
Silicon can do a lot of things, has a lot of thermal stability, but unfortunately (or perhaps fortunately for carbon-based critters) it does not appear to be able to form and re-form nearly as wide a variety of structures as does carbon.
connies4ever From Canada, joined Feb 2006, 4066 posts, RR: 13 Reply 17, posted (3 years 4 days 5 hours ago) and read 1759 times:
Quoting comorin (Reply 16): I got up and read your links - much appreciated.
I'm bouncing off the walls as this is the biggest thing in Science in my lifetime. Please let me know if I am mistaken.
Again, paging Dr Lightning, Stat...
I'm glad you took a look. Like the NBC News motto: the more you know.
Not sure this is the greatest thing since sliced bread, but it is definitely very interesting. It does to some degree widen our "field of view" regarding extra-terrestrial life -- what it might be, where and how it could possibly exist and thrive, and so forth.
Now, if we could unequivocably demonstrate that there either is or was life on Mars (or Europa, Enceladus, etc.) then I think that would definitely rank as one of the most amazing things in our species' history. The impact on society, philosophy, psychology, religion, and on and on would be simply enormous.
Yellowstone From United States of America, joined Aug 2006, 3071 posts, RR: 7 Reply 18, posted (3 years 4 days 5 hours ago) and read 1758 times:
Quoting comorin (Reply 16): I'm bouncing off the walls as this is the biggest thing in Science in my lifetime. Please let me know if I am mistaken.
Phosphorus and arsenic are pretty similar, chemically speaking (which is why arsenic is right below phosphorus in the periodic table). Both have 5 electrons in their valence shell, and both form ions with a -3 charge that have 4 oxygens bound in a tetrahedral configuration to the central phosphorus/arsenic. This phosphate ion is ubiquitous throughout biochemistry - among other things, it links together the sugars that form the backbone of DNA. Arsenate is toxic to most organisms because they try to use it in place of phosphate to make ATP. ATP stores chemical energy and shuttles it around the cell, but ATP made from arsenate is too unstable and so falls apart before it can deliver its energetic payload. Arsenic that's not in that ionic form is also toxic, because it binds to the sulfur in cysteine (one of the amino acids that make up proteins) and disrupts protein folding.
This strain of bacteria grows in arsenic-rich environments, so it obviously has a way to deal with this toxicity. It appears that it has evolved to be less sensitive to the difference between arsenate and phosphate, allowing it not to be poisoned if one is accidentally swapped for the other. However, while other arsenic-proof organisms might just discard the arsenate-containing biomolecules, it seems that this organism can actually still use them. If the cells are treated with solutions gradually containing more arsenate and less phosphate, eventually almost all of the phosphate can be replaced with arsenate, and the cell still functions (though not as well as it did before). However, as the researchers were unable to completely remove phosphate from the cell, it's not clear whether the cell is actually using the arsenate-containing molecules or if it's just using the tiny bit of phosphate that's left.
To use an analogy - imagine that you've built a carpentry robot that's designed to build chairs out of oak. One day, you run out of oak, so instead you give it balsa wood. The difference in density of the wood would cause most carpentry robots to screw up, but yours is able to use the balsa instead of the oak and still build a chair. Of course, it's not a very good chair, since balsa is a lot weaker. Replace oak with phosphorus, balsa with arsenic, and robot with cell, and that's the basic idea. It's nifty, but not earth-shaking.
Hydrogen is an odorless, colorless gas which, given enough time, turns into people.
comorin From United States of America, joined May 2005, 4861 posts, RR: 16 Reply 19, posted (3 years 4 days 4 hours ago) and read 1748 times:
Thanks Yellowstone for taking the time to explain - you certainly know your molecules! The thing about this that's exciting is the substitution of Phosphorus for Arsenic in the DNA itself. Was there a substitution in the ATP cycle too?
soon7x7 From , joined Dec 1969, posts, RR: Reply 22, posted (3 years 2 days 23 hours ago) and read 1617 times:
Changed my life forever with this announcement...nice to know that if this administration gets re elected I now will have options of relocation. I do believe a sign of intelligent life WAS indeed found on planet earth, somewhere in the D.C. district...actually, that's all it was, ...a "sign" that read..."office of US intelligence". It did however turn out to be a mirage in a desert of vacuous humanity.
connies4ever From Canada, joined Feb 2006, 4066 posts, RR: 13 Reply 24, posted (2 years 12 months 4 days 4 hours ago) and read 1488 times:
Quoting comorin (Reply 23): Looks like the scientific community is in an uproar over the article - lots of accusations of poor methodology and less than stringent peer review. Oh well, nice while it lasted...
Remains to be seen who's in the right on this. Never underestimate the egos involved in the scientific world, and the lengths they will go to to either a) prove their assertion, or b) try to make the other guy look like either an idiot or a liar. Seen it for decades, it's almost like a soap opera.
Nostalgia isn't what it used to be.
25 Yellowstone: Not so much anymore. There's three huge flaws in the paper's claims: - They used a purification technique that doesn't remove arsenate that just stic
26 comorin: I find it hard to believe that an august body such as NASA could be that wrong about something - I mean, NASA is right along there with Mom and Apple
27 connies4ever: NASA is as fallible as any other organisation. My chemistry is still pretty much 2nd year, so I have to defer to superior knowledge, but the Slate ar