Toward Future Engineering of the N-Glycosylation Pathways in Microalgae for Optimizing the Production of Biopharmaceuticals

Microalgae are eukaryotic and photosynthetic organisms which are commonly used in biotechnology to produce high added value molecules. Recently, biopharmaceuticals such as monoclonal antibodies have been successfully produced in microalgae such as Chlamydomonas reinhardtii and Phaeodactylum tricornutum. Most of these recombinant proteins are indeed glycosylated proteins, and it is well established that their glycan structures are essential for the bioactivity of the biopharmaceuticals. Therefore, prior to any commercial usage of such algae-made biopharmaceuticals, it is necessary to characterize their glycan structures and erase glycosylation differences that may occur in comparison with their human counterpart. In this context, the chapter summarizes successful attempts to produce biopharmaceuticals in microalgae and underlines current information regarding glycosylation pathways in microalgae. Finally, genome editing strategies that would be essential in the future to optimize the microalgae glycosylation pathways are highlighted.