Journal of Radioanalytical and Nuclear Chemistry

, Volume 295, Issue 2, pp 1235–1243 | Cite as

Solid state radiolysis of non-proteinaceous amino acids in vacuum: astrochemical implications

  • Franco Cataldo
  • Giancarlo Angelini
  • Yaser Hafez
  • Susana Iglesias-Groth
Article

Abstract

The analysis of the amino acids present in Murchison meteorite and in other carbonaceous chondrites has revealed the presence of 66 different amino acids. Only eight of these 66 amino acids are proteinaceous amino acids used by the present terrestrial biochemistry in protein synthesis, the other 58 amino acids are somewhat “rare” or unusual or even “unknown” for the current terrestrial biochemistry. For this reason in the present work a series of “uncommon” non-proteinaceous amino acids, namely, l-2-aminobutyric acid, R(−)-2-aminobutyric acid, 2-aminoisobutyric acid (or α-aminoisobutyric acid), l-norleucine, l-norvaline, l-β-leucine, l-β-homoalanine, l-β-homoglutamic acid, S(−)-α-methylvaline and dl-3-aminoisobutyric acid were radiolyzed in vacuum at 3.2 MGy a dose equivalent to that emitted in 1.05 × 109 years from the radionuclide decay in the bulk of asteroids or comets. The residual amount of each amino acid under study remained after radiolysis was determined by differential scanning calorimetry in comparison to pristine samples. For optically active amino acids, the residual amount of each amino acid remained after radiolysis was also determined by optical rotatory dispersion spectroscopy and by polarimetry. With these analytical techniques it was possible to measure also the degree of radioracemization undergone by each amino acid after radiolysis. It was found that the non-proteinaceous amino acids in general do not show a higher radiation and radioracemization resistance in comparison to the common 20 proteinaceous amino acids studied previously. The unique exception is represented by α-aminoisobutyric acid which shows an extraordinary resistance to radiolysis since 96.6 % is recovered unchanged after 3.2 MGy. Curiously α-aminoisobutyric acid is the most abundant amino acid found in carbonaceous chondrites. In Murchison meteorite α-aminoisobutyric acid represents more than 20 % of the total 66 amino acids found in this meteorite.

Keywords

Amino acids Radiolysis DSC ORD Racemization Astrochemistry Asteroids Meteorites 

References

  1. 1.
    Ehrenfreund P, Bernstein MP, Dworkin JP, Sandford SA, Allamandola LJ (2001) Astrophys J 660:L95CrossRefGoogle Scholar
  2. 2.
    Kanavarioti A, Mancinelli RL (1990) Icarus 84:196CrossRefGoogle Scholar
  3. 3.
    Stocker CR, Bullock MA (1997) J Geophys Res 87:10069Google Scholar
  4. 4.
    Aubrey AD, Cleaves HJ, Chalmers JH, Skelley AM, Mathies RA, Grunthaner FJ, Ehrenfreund P, Bada JL (2006) Geology 34:357CrossRefGoogle Scholar
  5. 5.
    Kminek G, Bada JL (2006) Earth Planet Sci Lett 245:1CrossRefGoogle Scholar
  6. 6.
    Ten Kate IL, Garry JRC, Peeter Z, Quinn R, Foing B, Ehrenfreund P (2005) Meteorit Planet Sci 40:1185CrossRefGoogle Scholar
  7. 7.
    Ten Kate IL, Garry JRC, Peeter Z, Quinn R, Foing B, Ehrenfreund P (2006) Planet Space Sci 54:296CrossRefGoogle Scholar
  8. 8.
    Martins Z, Sephton MA (2009) Extraterrestrial amino acids. Chapter 1 in Amino acids, peptides and proteins in organic chemistry. In: Hughes AW (ed) Origins and synthesis of amino acids, vol 1. Wiley–VCH, WeinheimGoogle Scholar
  9. 9.
    Draganic IG, Draganic ZD, Adloff JP (1993) Radiation and radioactivity on the earth and beyond. CRC Press, Boca RatonGoogle Scholar
  10. 10.
    Iglesias-Groth S, Cataldo F, Ursini O, Manchado A (2011) Mon Not R Astron Soc 410:1447Google Scholar
  11. 11.
    Cataldo F, Angelini G, Iglesias-Groth S, Manchado A (2011) Radiat Phys Chem 80:57CrossRefGoogle Scholar
  12. 12.
    Cataldo F, Ragni P, Iglesias-Groth S, Manchado A (2011) J Radioanal Nucl Chem 287:573CrossRefGoogle Scholar
  13. 13.
    Cataldo F, Ragni P, Iglesias-Groth S, Manchado A (2011) J Radioanal Nucl Chem 287:903CrossRefGoogle Scholar
  14. 14.
    Cataldo F, Ursini O, Angelini G, Iglesias-Groth S, Manchado A (2011) Rend Phys Acc Lincei 22:81CrossRefGoogle Scholar
  15. 15.
    Urey HC (1955) Proc Natl Acad Sci 41:127CrossRefGoogle Scholar
  16. 16.
    Urey HC (1956) Proc Natl Acad Sci 42:889CrossRefGoogle Scholar
  17. 17.
    Pizzarello S, Cronin JR (2000) Geochim Cosmochim Acta 64:329CrossRefGoogle Scholar
  18. 18.
    Pizzarello S, Huang Y, Alexandre MR (2008) Proc Natl Acad Sci 105:3700CrossRefGoogle Scholar
  19. 19.
    Meierhenrich UJ (2008) Amino acids and the asymmetry of life. Springer, BerlinGoogle Scholar
  20. 20.
    Freeland S (2009) Terrestrial amino acids and their evolution. Chapter 2 in Amino acids, peptides and proteins in organic chemistry. In: Hughes AW (ed) Origins and synthesis of amino acids, vol 1. Wiley–VCH, WeinheimGoogle Scholar
  21. 21.
    Djerassi C (1960) Optical rotatory dispersion applications to organic chemistry. McGraw-Hill, New YorkGoogle Scholar
  22. 22.
    Gargaud M (editor-in chief) (2011) Encyclopedia of astrobiology, vol 1. Springer, Berlin, p. 39Google Scholar
  23. 23.
    Weber AL, Miller S (1981) J Mol Evol 17:273CrossRefGoogle Scholar
  24. 24.
    Goodfriend GA, Collins MJ, Fogel ML, Macko SA, Wehmiller JF (2000) Perspectives in amino acid and protein geochemistry. Oxford University Press, OxfordGoogle Scholar
  25. 25.
    Guijarro A, Yus M (2009) The origin of chirality in the molecules of life. RSC Publishing, CambridgeGoogle Scholar

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2012

Authors and Affiliations

  • Franco Cataldo
    • 1
    • 2
  • Giancarlo Angelini
    • 3
  • Yaser Hafez
    • 4
  • Susana Iglesias-Groth
    • 5
  1. 1.Istituto Nazionale di Astrofisica, Osservatorio Astrofisica di CataniaCataniaItaly
  2. 2.Lupi Chemical ResearchRomeItaly
  3. 3.Istituto di Metodologie Chimiche, CNRMonterotondo Stazione, RomeItaly
  4. 4.National Center for Astronomy, KACSTRiyadhSaudi Arabia
  5. 5.Instituto de Astrofisica de CanariasLa LagunaSpain

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