Untitled

Abstract

The Yamato-791198 and Murchison carbonaceous chondrites were analyzed for dipeptides and diketopiperazines as well as amino acids and hydantoins by gas chromatography combined with mass spectrometry. Glycylglycine (gly-gly) and cyclo(gly-gly) were detected at the concentrations of 11 and 18 pmol g-1, respectively, in Yamato-791198, and 4 and 23 pmol g-1, respectively, in Murchison. No other dipeptide and diketopiperazine were detected. Five hydantoins were detected at 8 to 65 pmol g-1 in Yamato-791198 and seven in Murchison at 6 to 104 pmol g-1. Total concentration of the glycine (gly) dimers is approximately four orders of magnitude less than the concentration of free gly in Yamato-791198, and three orders of magnitude less than that in Murchison. The absence of L- and LL-stereoisomers of dipeptides consisting of protein amino acids indicates that gly-gly and cyclo(gly-gly) detected are native to the chondries and not from terrestrial contaminants. A possibility was discussed that the gly dimers might have been formed by condensation of gly monomers but not formed through N-carboxyanhydrides of gly.

From the Prebiotic Synthesis of α-Amino Acids Towards a Primitive Translation Apparatus for the Synthesis of Peptides

“…Amides, N-alkyl amides, lactams, hydantoins have been identified in both Murchison and Yamoto-791198 meteorites [63,65], confirming preliminary results from Cooper and Cronin [66]. The only peptides identified until now are diglycine and diketopiperazine (cyclic diglycine).…”

Where's water? The many binding sites of hydantoin

“…So far, hydantoin has been detected in carbonaceous chondrites together with several amino acids by gas chromatography combined with mass spectrometry. 7 This finding points to reaction pathways connecting hydantoin and amino acids. More recently, laboratory studies on interstellar ice analogues revealed that the hydrolysis of hydantoin, under acidic conditions, can produce small amino acids such as glycine, which is one of the building blocks of life.…”

Thermal Wet Decomposition of Prussian Blue: Implications for Prebiotic Chemistry

“…This result was checked by heating of standard solutions of 5,5-dimethylhydantoin in NH 4 OH (pH 12). 5,5-Dimethylhydantoin was previously detected in acid-hydrolyzed HCN polymers [29] and in carbonaceous chondrites such as Murchinson [30] and Yamato-791198 [31]. In those cases, the formation of hydantoins is explained by reaction between cyanate and amino acids to form the N-carbamoyl derivatives, which, in turn, may cyclize to hydantoins.…”