Astrobiology is highly multi-disciplinary.
Our
Astrobiology Nordic Project
brings together many of the different disciplines and has
led to a series of meetings
(I,
II,
III,
IV,
School).
Central to the question of the origin of life is the polymerization of
the first complex molecules that can have catalytic properties and that
would eventually carry genetic information.
It is widely accepted that our current life form involving DNA carrying
the genetic code and RNA producing the proteins that, in turn, catalyze
the production of nucleotides, must have been preceded by a simpler
life form called the RNA world.
The RNA of all terrestrial life forms involves a backbone of
dextrorotatory (right-handed) ribose sugars.
Theoretically, life could have been equally well based on levorotatory
(left-handed) sugars.
This so-called homochirality of left-handed amino acids and of right-handed
sugars in living cells can be explained as the result of two combined
effects, auto-catalytic production of similar nucleotides
during their first polymerization events and a competition
between left- and right-handed nucleotides.
Further reading:
Brandenburg, A., Andersen, A. C., & Nilsson, M.: 2005, ``Dissociation in a polymerization model of homochirality,'' Orig. Life Evol. Biosph. 35, 507-521
(q-bio/0502008, ADS, PDF)
Brandenburg, A., Andersen, A. C., Höfner, S., &
Nilsson, M.: 2005, ``Homochiral growth through enantiomeric cross-inhibition,'' Orig. Life Evol. Biosph. 35, 225-241
(q-bio/0401036, ADS, PDF)
Multamäki, T., & Brandenburg, A.: 2005, ``Spatial dynamics of homochiralization,'' Int. J. Astrobiol. 4, 75-80
(q-bio/0505040, ADS, PDF)
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