Our current research involves the study https://www.selleckchem.com/products/prt062607-p505-15-hcl.html of the enantiomeric (d/l mirror image) and isotopic properties of meteoritic sugar acids (Cooper et al., 2001). In life as we know it, only one of two possible enantiomers are used in proteins (l amino acids) and nucleic acids (d sugars), these polymers are homochiral. In a natural (non-biological) process, such as that expected to have operated on the parent-body of the meteorites, equal amounts of d and l enantiomers should be synthesized because (as far as we know) enantiomers have equal energies of formation. Equal d/l abundances are the norm for the vast majority of chiral meteoritic
compounds, however, some meteorite amino acids contain enantiomeric excesses (Pizzarello et al., 2006). Due to their structural relationships to organic compounds used in biochemistry, the analysis of enantiomer ratios of meteoritic compounds may have implications for understanding the origins of homochirality on Earth. In the case of enantiomeric analysis of meteorite sugar acids we have successfully separated
several enantiomer pairs and analyses of the Murchison and Murray meteorites show that in the majority of individual acids there are equal abundances of enantiomers, however there appear to be exceptions. There are indications selleckchem of enantiomeric excesses in four and five-carbon sugar acids that are not easily explained by microbial action. In addition, in each series of four through six-carbon sugar acids, rare as well as common compounds are present: an indicator of an abiotic synthesis process. The smallest of the meteorite sugar acids, glyceric, is also the most widely distributed on Earth in biological systems and would appear to be the most likely to contaminate meteorite samples. However meteoritic
glyceric is consistently racemic and a 13C analysis shows it to be of extraterrestrial origin. Results of further enantiomeric and isotopic analyses as well many as studies on microorganisms will be presented. Cooper, G., Kimmich, N., Belisle, W., Sarinana, J., Brabham, K., and Garrel, L. (2001). Carbonaceous meteorites as a source of sugar-related organic compounds for the Early Earth. Nature, 414: 879–883. Pizzarello, S., Cooper, G. W., and Flynn, G. J. (2006). The Nature and Distribution of the Organic Material in Carbonaceous Chondrites and Interplanetary Dust Particles in Meteorites and the Early Solar System II, pp. 625–651. D. S. Lauretta and H. Y. McSween Jr. (eds.), University of Arizona Press, Tucson. E-mail: [email protected].arc.nasa.gov Dramatic Selleck PCI-32765 Alteration of the Thermal Behavior of Glycine by Ca-Montmorillonite Punam Dalai, Henry Strasdeit Department of Bioinorganic Chemistry, Institute of Chemistry, University of Hohenheim, 70599 Stuttgart, Germany An important but less studied aspect of chemical evolution is the interaction of organic matter with its inorganic environment.