The microalga Chlamydomonas reinhardtii as a factory for the production of recombinant protein

There is increasing interest in the use of microalgae for biotechnological applications. Although biotechnological processes based on transgenic microalgae are still in their infancy, researchers and companies are considering the potential of microalgae as green cell-factories to produce heterologous proteins for pharmaceutical applications. Chlamydomonas reinhardtii have been proposed with more advantages including: 1) short time from transformation to scaling up; 2) ease of cultivation (it can be grown in enclosed bioreactors or outdoor ponds using an aqueous salt solution, daylight and a shaking platform); 3) safety, because it doesn’t harbor human pathogens (considered as GRAS by the FDA); 4) homogeneity of protein production; 5) easy generation of stable transgenic or transplastomic strains; 6) its three genomes (nuclear, plastidial and mitochondrial) have been completely sequenced; 7) its entire biomass is edible; and finally 8) recombinant protein producing algae can be easily preserved by lyophilization and stored and distributed at ambient temperature. While C. reinhardtii nuclear expression is subject to position effect and gene silencing but it can do most post translational modification as eukaryotic cell.C. reinhardtii chloroplastic expression is well established. Chloroplast lacks the machinery to perform post translational modifications, allows the formation of disulfide bonds, is able to perform some types of phosphorylation, and contains low protease levels as well as several molecular chaperones aiding protein folding. Moreover, C. reinhardtii has a single chloroplast with about 80 genome copies which facilitated the conversion of all copies of the chloroplast genome to the recombinant form.We are developing a platform for the production of recombinant proteins in microalga as host system that will allow for the expression of proteins from various sources and for different projects as: I) nuclear expression of Human Calcitonin, II) chloroplast expression of malaria candidate antigen, Plasmodium falciparum cell-traversal protein for ookinetes and sporozoites (PfCelTOS), III) nuclear and chloroplast expression of VP28 protective antigen of White Spot Syndrome (WSS) in shrimps.