NASA Arsenic Files

Rewriting the biology books! And I'm positive this is the only time we may see a press conference where the scientist credited with a profound discovery uttered the words, "I'd like to introduce to you, the bacteria." Later, one of the panel compared the discovery to the Horta on Star Trek (1967). I was quite nearly beside myself with the wonderfulness of this hour on NASA Television yesterday.


I kept my favorite space and technology blogs open in browser tabs, and a good percentage of them posted before the conference even reached the Q&A session, LOL! I'm not in that much of a hurry. I'd make a terrible "breaking news" reporter, because I like to ponder topics, discuss them at length, perhaps even allow for an R.E.M. phase before I develop an emotion about a newsworthy event.

Dr. Felisa Wolfe-Simon, in all her youthful, attractive, nose-pierced glory, was an eloquent and erudite speaker, who announced that her team discovered a microbe that can substitute arsenic for phosphorous. Everyone can enjoy reruns on NASA’s YouTube Channel, if you missed the live broadcast.

Within moments, I saw explosions on Facebook about "toxic-chemical based life form" or "arsenic-eating bacteria" –- so this message should have been clearer: THIS IS NOT AN ARSENIC-BASED LIFE FORM, NOR DOES IT EAT ARSENIC.

Of the six accepted components needed for life (carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur or CHNOPS), one is missing from these tiny rebels, and in what would normally be considered the phosphate backbone of their DNA helix, they can subsist upon another element that we hitherto considered lethal.

GFAJ-1

Compared to what we generally understand about Deoxyribonucleic Acid, to find a microbe performing differently than all other life as we know it, is startling in its profundity – though perhaps not entirely surprising in the greater realm of biology.

(Retro-viruses, for instance, are so named because they present a reverse transcriptase anomaly, and scientists have found critters who live in steam vents and ice. So, our minds have been pre-stretched by these valuable discoveries. I also try to remember that we have barely cataloged even a fraction of the living species in our oceans; what we know is always dwarfed by what we don't know.)

My first thought was how superbly this displays ADAPTABILITY. A bacterium took something from its ecosystem that is considered poisonous, used it to its advantage, then created similarly capable progeny. Other bacteria might die under such conditions, but one little chap found a way to survive, and this is a fine demonstration of natural selection right before our very eyes.

We aren't truly "re-writing" the rules as we find such delightful exceptions, we're just getting all the rules straight! I particularly liked her anecdote: "It's thinking about life in a planetary context." Quite so. When we look elsewhere for life, we must broaden the scope of possibilities. We are always seeking to find the "constants" on our own planet, and entertaining the notion that "constants" may be different elsewhere.

My other favorite quotable moment was ecologist Dr. James Elser, both complimenting and mildly admonishing Simon-Wolfe, when he cracked, "We thank you and blame you for making our lives more difficult!"


I don't think it will be as difficult as he surmises, however. We will see multiple scientific studies attempting to verify the results, and see if any other bacteria can be encouraged to make exotic substitutions. We have already found in other areas of study that adaptability is highly variable... so while many people are considering this an Earth-shattering finding right now, what will ultimately measure its success is the day we find it "mundane."

NASA Goddard Astrobiologist Pamela Conrad summed this up artfully: "This makes me have to expand my notion of what environmental constituents might enable habitability."

What is essential to life and what is simply tolerated chemically? What are the metrics for habitability, and if new ones developed, can they be passed on genetically? What is downright essential? What is unlikely or impossible? We keep thinking we know this. We keep finding out we're on a much longer journey.


Of course, XKCD weighed in, and said what no one else was willing to say aloud -– that at one time or another, we've all fantasized about slipping the general media some arsenic, LOL...