MSc defense Tanja Domeyer

Title of MSc Thesis

Towards sugar-based growth of Chlamydomonas reinhardtii

Abstract

Unicellular microalgae like Chlamydomonas reinhardtii have great potential as novel heterologous expression hosts for the production of monoclonal antibodies, oral vaccines and other valuable complex proteins and metabolites. However, difficulties in achieving high cell densities in production systems hampers commercial utilization.

Most microalgae including C. reinhardtii can grow phototrophically using light as energy source and carbon dioxide as carbon source. However, phototrophic growth is limited by mutual shading of the cells even at moderate densities, which is problematic for scaling up production in photobioreactors.

This master project set out to enhance achievable cell densities by enabling heterotrophic growth on glucose as carbon source. C. reinhardtii does not grow on glucose as it is not able to take it up from the media, and because it harbors a highly compartmentalized glycolytic pathway, whose first stage is located almost completely in the chloroplast. To achieve glucose uptake and utilization, a transport engineering approach was used, attempting to express a number of heterologous transport proteins in the plasma and chloroplast membranes and observing the effect on C. reinhardtii’s glucose uptake abilities and growth.

Censor

Professor Uffe Hasbro Mortensen, Technical University of Denmark

Supervisor

Associate Professor Hussam H. Nour-Eldin