Perspective for the use of genetic transformants in order to enhance the synthesis of the desired metabolites: Engineering chloroplasts of microalgae for the production of bioactive compounds

Abstract

Eukaryotic microalgae have recently gained particular interest as bioreactors because they provide attractive alternatives to bacterial, yeast, plant and other cell-based systems currently in use. Over the last years there has been considerable progress in genetic engineering technologies for algae. Biotechnology companies start to apply these techniques to alter metabolic pathways and express valuable compounds in different cell compartments. In particular, the eukaryotic unicellular alga Chlamydomonas reinhardtii appears to be a most promising cell factory since high amounts of foreign proteins have been expressed in its chloroplast compartment. For this alga the complete nuclear, plastidal and mitochondrial genome sequences have been determined and databases are available for any searching or cloning requirements. Apart from being easily transformable, stable transgenic strains and production volumes in full containment can be obtained within a relatively short time. Furthermore, C. reinhardtii is a green alga which belongs to the category of organisms generally recognized as safe (GRAS status). Thus, enhancing food with edible algae like Chlamydomonas engineered to (over)produce functional ingredients has the potential to become an important factor in food and feed technologies. © 2010 Landes Bioscience and Springer Science+Business Media, LLC.