Stereoisomeric specificity and soil gas disequilibria: implications for martian life detection

Variations in the atmospheric composition of soil samples were monitored by mass spectrometry after the addition of mixtures of D- and L-carbohydrates and/or amino acids. The changes in concentrations of CO2 in these experiments were found to be related to the steroisomeric configurations of the compounds with which the soil samples were enriched. The potential of this relationship provides a comparatively simple approach for detecting life in extraterrestrial soils.