Recent research has focused on engineering microbial biocatalysts to synthesize “drop-in” advanced biofuels. The challenges are that these biocatalysts have low yields, titers, and productivities and are engineered under conditions that are not practical for industrial scale-up processes (e.g., simple sugars, complex medium, aerobic condition, free of inhibitors). This section will focus on contributions that present the state-of-the-art metabolic engineering and synthetic biology approaches to address these challenges.

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