NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Enigmatic Isovaline: Investigating the Stability, Racemization, and Formation of a Non-biological Meteoritic Amino AcidAmong the Murchison meteoritic amino acids, isovaline stands out as being both nonbiological (non-protein) and having a relatively high abundance. While approximately equal amounts of D- and L-isovaline have been reported in Murchison and other CM meteorites, the molecule's structure appears to prohibit its racemization in aqueous solutions. We recently have investigated the low-temperature solid-phase chemistry of both isovaline and valine with an eye toward each molecule's formation, stability, and possible interconversions of D and L enantiomers. Ion-irradiated isovaline- and valinecontaining ices were examined by IR spectroscopy and highly-sensitive liquid chromatography/time-of-flight mass spectral methods to assess both amino acid destruction and racemization. Samples were studied in the presence and in the absence of water-ice, and the destruction of both isovaline and valine was measured as a function of radiation dose. In addition, we have undertaken experiments to synthesize isovaline, valine, and their amino acid isomers by solid-phase radiation-chemical pathways other than the oft-invoked Strecker process. This presentation will review and summarize some of our recent findings. -- Our work has been supported by a grant to the Goddard Center for Astrobiology through the NASA Astrobiology Institute. Experiments were performed in the Cosmic Ice Laboratory (RLH, MHM, AL) and the Astrobiology Analytical Laboratory (JPD, DPG) at the NASA Goddard Space Flight Center.
Document ID
20080044892
Acquisition Source
Goddard Space Flight Center
Document Type
Conference Paper
Authors
Hudson, Reggie
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Moore, Marla
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Lewis, Ariel
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Dworkin, Jason
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Date Acquired
August 24, 2013
Publication Date
April 14, 2008
Subject Category
Aerospace Medicine
Meeting Information
Meeting: Astrobiology Science Conference
Location: Santa Clara,CA
Country: United States
Start Date: April 14, 2008
End Date: April 17, 2008
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available