NASA Finding re Extraterrestrial Life

[RealityRules]

Loki had it at post #5 http://skymania.com/wp/2010/11/alien...-on-earth.html

Microbe found that substitutes Arsenic (As) for Phosphorus (P) in DNA and other molecules like ATP.

Both are close in the periodic table and have similar characterisitcs.

en.wikipedia.org/wiki/Arsenic#Physical_characteristics

http://en.wikipedia.org/wiki/Arsenic#Compounds

Previously had considered 6 essential "building-block" elements in organic chemistry - C, N, O, H, P and S.

This is a substitution of one of the "biggies" !!

As is not toxic at low concentrations - it has been a used as a tonic and appetitie stimulant in animals and humans. It was implicated in Phar Lap's death (Phar Laps strapper seemed to be using it, but there was a view a "higher-than-tonic" dose was administered)

http://en.wikipedia.org/wiki/Phar_Lap#Death

Implications for

1. consideration for formation of all "biomolecules" (organic chemicals/molecules) including all biological life on earth*, and
2. what they look for in
   1. other environs on Earth, and
      
   2. in other environs outside Earth.

* referred to evolutionary incorporation of microbes as intra-cellular organelles in all mammalian cells.

Implications for instrumentation used in extra-terrestrial exploration.