NASA News Conference on Astrobiology Discovery: Arsenic biochemistry?

The more this drags out, the more clear it seems that this result has been overstated. It is not even clear that the arsenic is participating in biochemistry. Going by the various responses from the science blogosphere, it seems debatable whether this even has much relevance to astrobiology. A good example of a sceptical response to this is at Rosie Redfield's blog RRResearch.

One amusing thing is the response from the primary author: the quote from this article from Felisa Wolfe-Simon is as follows:

"Any discourse will have to be peer-reviewed in the same manner as our paper was, and go through a vetting process so that all discussion is properly moderated," wrote Felisa Wolfe-Simon of the NASA Astrobiology Institute. "The items you are presenting do not represent the proper way to engage in a scientific discourse and we will not respond in this manner."

Which is incredibly amusing as this has now been released to the world via the method of press release, which is surely not the peer-reviewed process! Sorry, you do not get to restrict discussion to the scientific media if you go down the press release route...

While I'm not as familiar with the subject as I'd like to be, it's becomming apparent that a lot more work should have been done in this research before making the press release.

What a mess...

Study Fails to Confirm Existence of Arsenic-Based Life

Rosie Redfield has taken an interesting "open research" approach, posted on the RRResearch blog... we shall see whether this open-access model is a direction that is going to take hold.

Evidence fails to support the arsenic-based life.
http://www.sciencemag.org/content/early/2012/07/06/science.1219861

A strain of Halomonas bacteria, GFAJ-1, has been claimed to be able to use arsenate as a nutrient when phosphate is limiting, and to specifically incorporate arsenic into its DNA in place of phosphorus. However, we have found that arsenate does not contribute to growth of GFAJ-1 when phosphate is limiting and that DNA purified from cells grown with limiting phosphate and abundant arsenate does not exhibit the spontaneous hydrolysis expected of arsenate ester bonds. Furthermore, mass spectrometry showed that this DNA contains only trace amounts of free arsenate and no detectable covalently bound arsenate.

Continuing on the theme of Dr Redfield's open research:

RRResearch: Consider the publication embargo...
Embargo Watch: Another chink in the Ingelfinger armor? Arsenic life talk forces Science to release paper early, without embargo

"Interesting times" for science publishers these days!

GFAJ-1 appears to be able to filter out arsenic from getting inside it.
http://news.discovery.com/earth/bacteria-filters-arsenic-121004.html

For those of you fluent in spanish , here comes another alien-like lifeform on Earth , Pseudomonas pseudoalcaligenes , they breath cianure and excretes biodegradable polymers , on ph> 9.5 enviroment. A very thougth customer.
Wonder what kind of planet is paradise to this bugs.

Edit : here comes a link to an english pdf : Biodegradation of cyanide-containing wastes by Pseudomonas