The effects of parent body processes on amino acids in carbonaceous chondrites

Abstract

Abstract-To investigate the effect of parent body processes on the abundance, distribution, and enantiomeric composition of amino acids in carbonaceous chondrites, the water extracts from nine different powdered CI, CM, and CR carbonaceous chondrites were analyzed for amino acids by ultra performance liquid chromatography-fluorescence detection and time-of-flight mass spectrometry (UPLC-FD ⁄ ToF-MS). Four aqueously altered type 1 carbonaceous chondrites including Orgueil (CI1), Meteorite Hills (MET) 01070 (CM1), Scott Glacier (SCO) 06043 (CM1), and Grosvenor Mountains (GRO) 95577 (CR1) were analyzed using this technique for the first time. Analyses of these meteorites revealed low levels of two-to five-carbon acyclic amino alkanoic acids with concentrations ranging from approximately 1 to 2,700 parts-per-billion (ppb). The type 1 carbonaceous chondrites have a distinct distribution of the five-carbon (C 5 ) amino acids with much higher relative abundances of the c-and d-amino acids compared to the type 2 and type 3 carbonaceous chondrites, which are dominated by a-amino acids. Much higher amino acid abundances were found in the CM2 chondrites Murchison, Lonewolf Nunataks (LON) 94102, and Lewis Cliffs (LEW) 90500, the CR2 Elephant Moraine (EET) 92042, and the CR3 Queen Alexandra Range (QUE) 99177. For example, a-aminoisobutyric acid (a-AIB) and isovaline were approximately 100 to 1000 times more abundant in the type 2 and 3 chondrites compared to the more aqueously altered type 1 chondrites. Most of the chiral amino acids identified in these meteorites were racemic, indicating an extraterrestrial abiotic origin. However, nonracemic isovaline was observed in the aqueously altered carbonaceous chondrites Murchison, Orgueil, SCO 06043, and GRO 95577 with l-isovaline excesses ranging from approximately 11 to 19%, whereas the most pristine, unaltered carbonaceous chondrites analyzed in this study had no detectable l-isovaline excesses. These results are consistent with the theory that aqueous alteration played an important role in amplification of small initial left handed isovaline excesses on the parent bodies.

Determining Amino Acid Chirality in the Supernova Neutrino Processing Model

“…Each model is used to explore an increasingly larger range of angular speeds. Equation (6) shows that a quasi-resonant condition occurs in the magnetic field in the case where ∆ω = 0. For a time that is long compared with the relaxation time of the molecule, the difference in rotational frequency and the magnetic field resonance frequency increases, resulting in a larger polarization component parallel to the magnetic field vector and smaller perpendicular components of polarization.…”

“…Analyses of inclusions in meteoritic carbonaceous chondrites [1][2][3][4][5][6][7] have shown that the molecules of life, especially the amino acids, are made in outer space. Furthermore, some of the amino acids so synthesized tend to have the left-handed chirality that is observed almost entirely in earthly amino acids.…”

Radiólise De Aminoácido Sob Ação De Íons Pesados: Implicações Em Astroquímica E Astrobiologia

“…: raios cósmicos, radiação UV, raios X, elétrons e prótons) (SHEN et al, 2004), podem produzir compostos orgânicos complexos e moléculas pré-bióticas, tais como aminoácidos e nucleobases (MUÑOZ et al, 2002;KOBAYASHI et al, 2008;PILLING et al, 2009). A presença desses compostos pré-bióticos foi, também, observada em análises de laboratório de amostras de meteoritos, onde mais de 70 aminoácidos (dentre eles a glicina) foram identificados, como no caso do meteorito Murchison (CRONIN;PIZZARELLO, 1983;DWORKIN, 2009;GLAVIN et al, 2011). O entendimento sobre o comportamento da interação entre essas partículas de alta energia com as diversas superfícies espaciais (ex.…”

2-Methylaspartic acid monohydrate

“…The majority of meteoritic amino acids show little or no enrichment of one enantiomer over the other. However, a number of alpha methyl amino acids have been observed with L-enantiomeric excesses up to 20% that are not believed to be the result of contamination (Pizzarello & Cronin, 2000;Glavin & Dworkin, 2009;Glavin et al, 2011;Glavin et al, 2012;Burton et al, 2013). An intriguing question is the process that leads to the separation and enrichment of the L enantiomer over the D. There are several possible explanations for this including the role that crystallization plays (Blackmond et al, 2007;Glavin et al, 2012).…”

“…For normal bond lengths and angles, see: Orpen (1993). For the number ofmethyl amino acids that have been observed with l-enantiomeric excesses up to 20% that are not believed to be the result of contamination, see : Pizzarello & Cronin (2000); Glavin & Dworkin (2009);Glavin et al (2011Glavin et al ( , 2012; Table 1 Hydrogen-bond geometry (Å , ). …”