Enantiomeric Excesses in Meteoritic Amino Acids

Cronin, John R.; Pizzarello, Sandra

doi:10.1126/science.275.5302.951

Cited by 812 publications

(561 citation statements)

References 25 publications

Supporting

Mentioning

532

Contrasting

Unclassified

Order By: Relevance

“…Aqueous alteration is also related to the chiral excesses observed so that the β-alanine/AIB ratio correlates with the L/D chiral excess of isovaline. These data thus reaffirm and extend previous work on the correlation of enantiomeric excesses with aqueous alteration and the presence of hydrated phases in meteorite samples 17,28 .…”

Section: Introductionsupporting

confidence: 87%

Selective adsorption and chiral amplification of amino acids in vermiculite clay-implications for the origin of biochirality

Fraser

Fitz

Jakschitz

et al. 2011

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

Smectite clays are hydrated layer silicates that, like micas, occur naturally in abundance. Importantly, they have readily modifiable interlayer spaces that provide excellent sites for nanochemistry. Vermiculite is one such smectite clay and in the presence of small chain-length alkyl-NH 3 Cl ions, forms sensitive, 1-D ordered model clay systems with expandable nano-pore inter-layer regions. These inter-layers readily adsorb organic molecules. N-propyl NH 3 Cl vermiculite clay gels were used to determine the adsorption of alanine, lysine and histidine by chiral HPLC. The results show that during reaction with fresh vermiculite interlayers, significant chiral enrichment of either L-and D-enantiomers occurs depending on the amino acid. Chiral enrichment of the supernatant solutions is up to about 1% per pass. In contrast, addition to clay interlayers already reacted with amino acid solutions resulted in little or no change in D/L ratio during the time of the experiment. Adsorption of small amounts of amphiphilic organic molecules in clay inter-layers is known to produce Layer-by-Layer or Langmuir-Blodgett films. Moreover atomistic simulations show that self-organization of organic species in clay interlayers is important. These noncentrosymmetric, chirally active nanofilms may cause clays to act subsequently as chiral amplifiers, concentrating organic material from dilute solution and having different adsorption energetics for D-and L-enantiomers. The additional role of clays in RNA oligomerization already postulated by Ferris and others, together with the need for the organization of amphiphilic molecules and lipids noted by Szostak and others, suggests that such chiral separation by clays in lagoonal environments at normal biological temperatures might also have played a significant role in the origin of biochirality.2

show abstract

Section: Introductionsupporting

confidence: 87%

Selective adsorption and chiral amplification of amino acids in vermiculite clay-implications for the origin of biochirality

Fraser

Fitz

Jakschitz

et al. 2011

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

show abstract

“…Accurate mass measurements of [M+ H] + of the amino acids were carried out by scanning from 60 to 400m/z. The ion injection time was 50 ms with the automatic gain control (AGC, corresponding to the number of changes transferred from the front-stage ion trap to the orbitrap analyser) target set at 1×10 5 .…”

Section: Methodsmentioning

confidence: 99%

“…Most amino acids contain an asymmetric centre, and the analysis of L-or D-enantiomers is very important in several research fields, such as food chemistry [2], geochronology [3] and exploration of other planets [4]. The homochirality of life on Earth occurs because L-amino acids are the only enantiomers used during the biosynthesis of proteins and peptides [5]. To the contrary, the occurrence of certain D-amino acids in cell walls can be attributed to bacterial origin [6].…”

Section: Introductionmentioning

confidence: 99%

d- and l-amino acids in Antarctic lakes: assessment of a very sensitive HPLC-MS method

et al. 2014

View full text Add to dashboard Cite

Amino acids represent a fraction of organic matter in marine and freshwater ecosystems, and a source of carbon, nitrogen and energy. L-Amino acids are the most common enantiomers in nature because these chiral forms are used during the biosynthesis of proteins and peptide. To the contrary, the occurrence of D-amino acids is usually linked to the presence of bacteria. We investigated the distribution of L-and D-amino acids in the lacustrine environment of Terra Nova Bay, Antarctica, in order to define their natural composition in this area and to individuate a possible relationship with primary production. A simultaneous chromatographic separation of 40 L-and D-amino acids was performed using a chiral stationary phase based on teicoplainin aglycone (CHIROBIOTIC TAG). The chromatographic separation was coupled to two different mass spectrometers-an LTQ-Orbitrap XL (Thermo Fisher Scientific) and an API 4000 (ABSciex)-in order to investigate their quantitative performance. High-performance liquid chromatography coupled with mass spectrometry methods were evaluated through the estimation of their linear ranges, repeatability, accuracy and detection and quantification limits. The high-resolution mass spectrometer LTQ-Orbitrap XL presented detection limits between 0.4 and 7 μgL −1 , while the triple quadrupole mass spectrometer API 4000 achieved the best detection limits reported in the literature for the quantification of amino acids (between 4 and 200 ngL −1 ). The most sensitive method, HPLC-API 4000, was applied to lake water samples.

show abstract

“…However, Cronin and Pizzarello (1997) found L-enantiomer excesses (e.e.) in six a-methyl-a-amino acids from the Murchison (e.e.…”

Section: Meteoritesmentioning

confidence: 98%

E

2015

Encyclopedia of Astrobiology

View full text Add to dashboard Cite

DefinitionThe Earth is the planet on which we live. It is the third planet from the Sun and one of the telluric (small and rocky) planets of our ▶ Solar System. It has a mean radius of 6,371 km and a mean density of 5.515 g cm À3 . It is distinguished from other planets by the presence of ▶ continental crust, oceans, and ▶ life. Its unusually large core and satellite (the Moon) are believed to result from the collision of a Mars-sized body (protoplanet ▶ Theia) about 4.45 Ga ago.

show abstract

Enantiomeric Excesses in Meteoritic Amino Acids

Cited by 812 publications

References 25 publications

Selective adsorption and chiral amplification of amino acids in vermiculite clay-implications for the origin of biochirality

Selective adsorption and chiral amplification of amino acids in vermiculite clay-implications for the origin of biochirality

d- and l-amino acids in Antarctic lakes: assessment of a very sensitive HPLC-MS method

E

Contact Info

Product

Resources

About