Abstract

Application of microalgae for industrial purposes holds great potential and can aid in worldwide challenges such as food and energy shortage. The cost of added nutrients, such as vitamins and the cost associated with contamination from other microorganisms are currently two factors limiting the use of microalgae biotechnology. By co-culturing algae with appropriate bacteria, that can supply key nutrients and limit the opportunities for foreign organisms, it is possible to improve the efficiency of microalgae production systems and expand the industrial opportunities. My project will be based on the symbiosis model system of the bacterium Mesorhizobium loti and the microalga Lobomonas rostrata, where vitamin B12 is produced by the bacterium and supplied to the algae in return for a carbon source. I study their mutualistic interaction from a systems biology point of view using techniques such genome scale metabolic reconstruction and flux balance analysis to identify the metabolites and pathways involved in the interaction. In the first year of my project I have developed a genome scale metabolic reconstruction of M. loti and applied it to study organic energy sources useable by the bacterium.