Date of Graduation
Bachelor of Science
Chemistry & Biochemistry
The climate on the face of Mars is hostile towards life. Thus, any organisms potentially living on Mars would likely inhabit a subsurface environment, in which conditions are wetter and warmer. However, organisms living beneath the surface would be significantly deprived of light and some organic compounds necessary for the sustenance of most life. The discovery of methane gas in Mars’ atmosphere has led to speculation that methanogens, obligate anaerobes which produce methane as waste, are the organisms most likely to survive in a subsurface environment. These members of domain Archaea subsist on water, hydrogen, and carbon dioxide. In addition, like all organisms, methanogens depend on micronutrients such as vitamins and minerals for optimum growth. Iron is synonymous to Mars, and research by NASA has confirmed the existence of the compound ferric sulfate on the planet. It has been suggested that ferric sulfate brines could account for liquid water in the subsurface of Mars, in addition to the formation of the gullies via episodic transition from solid to viscous liquid flows. The goal of this project was to examine a potential link between methanogens and the iron compounds of the red planet. To this end, experiments were conducted in which the growth of methanogens in solutions of ferric sulfate and ferric nitrate was monitored. In order to replicate the droughts and floods of Mars, methanogens were desiccated and exposed to those same chemicals. The results of this study show that certain methanogens can survive in the presence of iron compounds. However, no results indicated that the organisms were utilizing these compounds as fuel.
Cowan, Monroe Phillip, "Methanogen Metabolism in the Presence of Iron Compounds: A Martian Environment Simulation" (2015). Chemistry & Biochemistry Undergraduate Honors Theses. 3.