Tuesday, December 7, 2010

arsenice and old life

you may have heard the buzz around NASA's press release last week regarding the bacteria found in california's mono lake which can build DNA using arsenic instead of the typically used ingredient phosphorus?

brady haran's university of nottingham project, periodic table of videos has tackled the topic in a very interesting way. watch below to learn more!

1 comment:

Unsui said...

Publishing the findings was probably inspired from Calvin & Hobbes

I had seen this story on science channel the day before and reason why I didn't catch my attention was I wasn't much surprised that because these organisms don't have arsenic based DNA structure. This is case of phosphorus based DNA structure which can use arsenic to create chemical bonds. I don't find arsenic replacing phosphorus surprising, after all both the elements are in same column of periodic table. Sci-fi authors have always played with idea of having organisms with DNA structure based on Silicon (instead of carbon based DNA structure), that logic was again based on the fact that Si is in same column as C and hence can have same chemical bonding with other elements as carbon.

Fun would be to actually create artificial DNA based on Si replacing Carbon. Si is prime ingredients of the web of electronics that Humans have weaved in past century and has resulted in smaller and smaller smart devices. Imagine these devices morphing into new life forms in future world and then evolving like the organisms in our carbon based world. That would be fascinating.

Point to note that when the organisms in Mon lake are move to environment deplete of Arsenic they revert back to their phosphorus based DNA structure. So its more of a evolution/mutation phenomenon rather than an alternate DNA based life form existence.
Of course this phenomenon gives possibility that in future due to climatic changes if the world is reduced to seas full of arsenic, the micro organisms based on phosphorus based DNA can still mutate and evolve with completely new DNA model that based on arsenic.

Humans may not last but life will....