CHAPTER 8. Genetic Engineering of Microalgae for the Production of High-value Metabolites: Status and Prospects

Microalgae, when compared to other biofactories, are easier to grow owing to their high photosynthetic efficiency, growth rate and yield. Yet, the technical and economic challenges associated with downstream processing of microalgae make commercialization of bioproducts from microalgae an uphill task. Although microalgae are highly diversified and bioprospecting might yield strains with varied capabilities, even after 140 years of laboratory culturing and 60 years of commercial farming, microalgae are yet to be a mainstream source for high-value metabolites. In this study, it is proposed that genetically modifying the currently available strains is the best solution for enhancing the sustainable microalgal market for high-value metabolites and to reduce dependence on synthetic products. This chapter presents a detailed overview of the tools, techniques and model organisms currently available for genetically engineered strains with enhanced production capabilities for high-value metabolites. The chapter also summarizes the advent of genome editing techniques, key genes that have been genetically manipulated, metabolic and regulatory networks, and the prospects for sustainable microalgal factories for the production of high-value metabolites.