a) The presence of natural amino acids with enantiomeric excess from the meteorite is still a...

a) The presence of natural amino acids with enantiomeric excess from the meteorite is still a subject of debate. Discuss why this is - what are the experimental issues with stating that alanine found on the Murchison meteorite has an excess of one (L) enantiomer? How might "false positives" be observed in the analysis of these meteorite samples?

b) An argument put forward to corroborate the meteorite theory is the presence of unnatural α-alkyl amino acids such as isovaline, which was observed to exist in the meteorite with a slight enhancement of the L isomer. Discuss why the observation of unnatural amino acids such as these is less susceptible to false positives than the presence of alanine above.

c) Assume that there was an excess of (L)-isovaline on the Murchison meteorite. Discuss the plausibility of (L)-isovaline conferring chirality on species such as 1, based on your reading of Noorduin, et al.

Expert Solution

queen_honey_blossom answered 2 years ago

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