Biosignature identification using mass spectrometry and infrared spectroscopy

GEOC 60

Beizhan Yan1, Daphne L. Stoner, stondl@if.uidaho.edu2, Nancy W. Hinman, nancy.hinman@umontana.edu3, J. Michelle Kotler3, William Bauer4, and Jill R. Scott, jill.scott@inl.gov5. (1) Department of Chemistry, University of Idaho-Idaho Falls, 1776 Science Center Drive, Suite 306, Idaho Falls, ID 83402, (2) Department of Chemistry, University of Idaho--Idaho Falls, 1776 Science Center Drive, Idaho Falls, ID 83402, (3) Geosciences Department, University of Montana, 32 Campus Dr., MC 1296, Missola, MT 59812-1296, (4) Chemistry Department, Idaho National Laboratory, Idaho Falls, ID 83415-2208, (5) Chemical Sciences, Idaho National Laboratory, 2525 N. Fremont Ave., MS 2208, Idaho Falls, ID 83415
We are applying laser desorption Fourier-transform mass spectrometry (LD-FTMS) and attenuated total reflectance infrared spectroscopy (ATR-IR) to identify biosignatures in secondary minerals and examine microbe-mineral interactions that lead to the development of biosignatures. We have examined the effects of Martian mineral analogues using LD-FTMS spectra obtained for microbial biomass, microbial exudates, microbial precipitates, amino acids and peptides. There was an indirect correlation between the presence of iron and the detection of amino acids and peptides as well as microbial biosignatures in amorphous iron precipitates formed by acidophilic iron-oxidizing bacteria. Natural iron-bearing minerals such as jarosite and iron precipitates derived from acidophilic microbial cultures were analyzed by ATR-IR; however, signals indicative of microbes or microbial exudates were relatively weak and ambiguous. In conclusion, LD-FTMS has the potential for detecting and interpreting biosignatures in terrestrial and extraterrestrial geomatrices.
 

Frontiers in Geochemistry: Commemorating the 25th Anniversary of the ACS-Geochemistry Division
9:00 AM-12:00 PM, Monday, 11 September 2006 Moscone Center -- Room 262, Oral

Division of Geochemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006