AWESOME STORY: THE FIRST

So every week I plan on giving some story about some interesting scientific thing. Already have the first few weeks planned out, unless something big occurs in that time, which it just so happened to this week.

For those yet to have heard, a recent discovery of a bacterium in California's Mono Lake (no relationship to the disease) able to use arsenic in replacement of phosphorous, has been making a large fuss in the scientific world. Why so amazing some may ask? Well the answer is simple enough. Arsenic is poisonous to cells, any cell. Life uses 6 elements for most everything, CHNOPS, carbon, hydrogen, nitrogen, oxygen, phosphorous, and sulfur. The problem with arsenic is that is has properties very similar to that of phosphorous, and due to these similarities the cell confuses the two and may replace arsenic for phosphorous. When this occurs, cell respiration gets blocked there by depriving the cell of ATP. This replacement of one of the big 6 demonstrates a long held belief that life can occur with a different chemical make-up, big news for astrobiologists.

In these new bacterium, GFAJ-1 a member of the Halomonadaceae family, arsenic is actually able to be incorporated into the cell without killing it. When grown in a arsenic heavy environment, the phosphorous content dropped to 1/13 of it's original dry weight. However they really don't like doing. For one, when this happens the cells become bloated with large vacuoles. Reason is unsure, but it may be because some arsenate-containing molecules become unstable in water so the cell creates isolated spots with little to no water. Secondly, the bacteria grow 40% slower.


The thing that get's every one in a tizzy is that the arsenate ion (AsO₄^3-) replaces the phosphate ion (PO₄^3-) in many well known molecules. These molecules include DNA, RNA, serine, tyrosine, threonine, ATP (or maybe ATA now?), and some amino acids.

But anyways, yes this gives credence to the idea that life can occur else where in the universe using different chemical make-ups. Maybe next we can find an organism that replaces carbon with silicon.

Find the paper here -> Effects of arsenic cell metabolism and cell proliferation
Or perhaps a wikipedia search is more your style, in which case search for GFAJ-1
You could be more of a blog reader though (especially if you're reading my crap)  so read my friend Charlie's blog My Ecological Niche, I also suggest Pharyngula for more information.

UPDATE:
As it turns out this story is actually way over hyped. While the possibility of such a thing is amazing, the experiment itself was actually performed with such bad techniques that no good analysis can be given about the results of this. As I am not a professional (yet), I shall rely upon a professional to give the critical analysis of the paper. Is it REALLY incorporating arsenic? This is a very long post, so if you don't want to read it, don't worry not many people will. It is laid out with much scientific jargon.