Molecular and chiral analyses of some protein amino acid derivatives in the Murchison and Murray meteorites

摘要: — The varied organic suite extracted from the Murchison meteorite contains several amino acids that are common to biosphere. Some of these have been found be non-racemic, but indigenous nature their L-enantiomeric excesses has subject debate in view possible terrestrial contamination. We investigated two and meteoritic occurrence, alanine glutamic acid, assessed enantiomeric ratios Murray meteorites through some derivatives. Analyzed were N-acetyl alanine, α-imino propioacetic acid pyroglutamic acid. Both derivatives racemic, while those showed varying 16% 47.2% for 8.6% 41% acid. δ13C was determined enantiomers both before after hydrolysis values +27.7%0 (D-pyro), +10.0%0 (L-pyro), +32.2%0 (D-glu) +14.6%0 (L-glu) obtained. The racemic strongly suggests itself, as meteorite, is racemic. explanation less direct; however, variability compounds distinctly lower L-enantiomer point a contamination, possibly dating time fall.