NASA's discovery of alien life

The story is distorted by the media. The new life is a bacteria that seems to be able to use different atoms in it's DNA that all known bacteria or any other life forms.

Yeah, it's not "alien" but it is pulling off one hell of a trick. To swop out phosphorus for arsenic, without killing itself in the process, is pretty neat. Of course Mars springs to mind. Mars cooled down faster than the Earth, so we could expect life to have got an earlier start. There would have been a window, when both Mars and the Earth had a reducing atmosphere, when heavier stuff could have made the journey to Earth, and lighter stuff, the journey from Earth to Mars.

Putting arsenic into the uprights of the dna ladder has to mean that the helixes are distorted, best guess, more open twists. The bacterium in question prefers to use phosphorus it seems. But, it can be done. I'd expect that NASA is taking another look at its Mars samples for possible novel genetic coding.

<b>[Jim] "The story is distorted by the media."</b>

Yes, it is. But the media are just doing what we pay them to do. Sometimes directly, but most often indirectly. If we stop paying them to distort, they will stop distorting.

Do you (or anyone else) know what the actual scientific report says, and if it has changed due to outside pressure? I've heard that this story was first talked about in some nook or crany of the press about 15 months ago, but that the investigators asked for discression from the press because they needed to verify some things - dot some Is, cross some Ts.

The rumor mill:
In particular I've heard that (certain elements of) the press pushed (hard?) to have at least one of the investigators use the words 'alien life' on paper. And that the investigators fought to avoid that. I have not heard how that particular battle worked out (or indeed if it ever really happened), but obviously the press went with that angle either way. It is a much more attention grabbing headline, so the pressure (press-ure? is obvious.

The press is not the only possible villain in this and other stories. Big Science uses them, they use Big Science. WE have to be careful to avoid believing <u>and not believing</u> until we or someone we trust has done some diggging behind the scenes.

I suppose that is part of the function of a group like this. Since experience teaches that we must be skeptical until we verify, and since it is not reasonable for each of us individually to verify everything, it becomes reasonable to rely on like minded people that have demonstrated, over time, the willingness and ability to dig and then shoot straight about what they find. Just remember to keep your primary focus on the scientific side of things, with an emphasis on astronomy and cosmology.

The group, <u>if it behaves itself</u>, can be a fairly good (but not perfect) distortion filter.

Regards,
LB

As I understand the story it was not NASA that made the find but a gal at USGS. She was poking around Mono Lake and found a bacteria that was a bit odd and dug a little deeper. You can find more at USGS if you need to-I was thinking about contacting her but its way too hot for me at this time.

From what I've read the story grew in the blogosphere. The research was done by a woman as some sort of NASA subcontract. As I understand it, and I haven't read that much of the blogosphere argument, some sections of it jumped to an episode from Star Trek. The one about a silicon based life form. Can such a thing exist? Silicon isn't as versatile as carbon, metabolic rates would be very slow, but it could exist, and the upright to the dna ladder would contain arsenic.

That obviously places a question mark over the origins of life on Earth. When I was looking at the question of "palindromic" dna code, I asked a few people why it should give advantages. No one knew. One thing I found, was that a toroidal dna strand is a mobius and has to have a certain number of twists in order to join up into a torus. Putting arsenic into the uprights has to mean an alteration in the twists.

Anyway, the implications for the origins of life are back on the drawing board.

Sorry, been monitoring but not commenting. Nucleic acids do not have to be double-stranded (i.e. palindromic) such as RNA, one of the benefits of DNA is that as well as being self-replicating, it is also self-correcting. DNA Polymerase enzyme (which is coded for by DNA) can actually analyze mismatches, mark, cut, and then DNA Ligase can seal the gap. So one strand templates the other, this functions to minimize base pair changes in the molecule. Arsenic in the phosphate backbone would not alter the configuration because its bonding geometry is nearly identical. The arsenic would not be elemental but like phosphate (PO4 3-), the polyatomic ion arsenate is AsO4 3-, this means that arsenic can essentially replace phosphates in the structure without interruption so long as the bacteria has other mechanisms that prevent the destructive properties of the arsenic. Arsenic poisons eukaryotic aerobes (multi-cellular organisms that use oxygen) via allosteric interference of pyruvate dehydrogenase enzyme. Since the bacteria was found in the mud of the lake that niche would be anaerobic meaning this bacteria uses anaerobic respiration and would not need the enzyme for pyruvate (which is part of aerobic respiration). Basically, bacteria wouldn't care really so long as the arsenic didn't mess up something else that THEY need.

Mark Vitrone