Synthetic biology for phytohormone production

Phytohormones are compounds produced by plants that can control the processes of plant development and are involved in defense mechanisms. They can serve as sustainable enhancers for plant growth and are also better alternatives to agrochemicals because of their bio-based nature and optimal safety profile towards mammalian cells. Although phytohormones are essential for plant growth, they are naturally synthesized by plants in varying quantities, influenced both by environmental and genetic factors. The synthesis of phytohormones, however, faces several hurdles, including challenges in optimizing the production process as well as difficulties in the extraction of these compounds for downstream applications. In this review, we critically evaluate synthetic biology approaches for phytohormone production, which provides a sustainable method for the production of important phytohormones including auxin, gibberellin (GA), and salicylic acid (SA). These three compounds are highly significant for the agricultural industry because of their widespread utilization.