Heterologous production of plant polyphenols with high therapeutic potential using combinatorial biosynthesis

Abstract

Polyphenols are plant secondary metabolites with an estimated market size of USD 3.3 billion by 2032. They exhibit diverse biological and potential therapeutic activities including anticancer, anti-inflammatory, antioxidant, cholesterol lowering, and estrogenic. However, these compounds typically accumulate in low quantities over extended growth periods, demanding significant investments in water, land, and time. The supply chain is also vulnerable to insecurities caused by pests and extreme weather conditions. Therefore, the extraction process is inefficient, environmentally unfriendly, and expensive, and the purification is difficult due to the need to separate the specific polyphenols from compounds with similar chemical structures. In response to these challenges, over the past decade, there has been a concerted effort to leverage synthetic biology approaches for polyphenol production. Our group has been focusing on the heterologous production of curcuminoids, coumarins, furanocoumarins, flavonoids and prenylflavonoids in Escherichia coli and/or Saccharomyces cerevisiae using artificial biosynthetic pathways with several steps in common from the phenylpropanoids pathway. Using genome engineering (CRISPR-Cas9), combinatorial biosynthesis, step-by-step optimization, and co-culture engineering strategies, we have optimized the production of these compounds using in specific cases glucose as substrate obtaining the highest titers reported so far (e.g., 95.8 mg/L curcumin and 765.9 mg/L naringenin in E. coli). These findings represent a noteworthy progression toward the large-scale sustainable production of these valuable polyphenols.