De Novo Biosynthesis of Violacein Utilizing Saccharomyces cerevisiae as a Cell Factory

Background Violacein is a naturally occurring purple pigment produced by microbes, commonly employed in synthetic biology as a readily detectable model compound. Despite its wide-ranging applications as an antimicrobial, antiviral, and antitumor compound, violacein production is hindered by low yield and strain instability, which are frequently affected by cultivation conditions. Furthermore, heterologous production remains limited to the laboratory scale. Consequently, rational design strategies for improving violacein biosynthesis have attracted increasing research interest. Results In this work, the violacein biosynthesis pathway was reconstructed in Saccharomyces cerevisiae ; however, no production of violacein was initially observed. Pathway analysis indicated that insufficient vioC expression contributed to the limited violacein output. By employing pathway engineering strategies—such as multicopy gene integration and overexpression—combined with fermentation medium optimization using the Box-Behnken design, violacein production in 250 mL shake flasks (with 100 mL culture volume) reached 143.89 mg/L, representing the highest yield reported in S. cerevisiae so far. Conclusions This study successfully demonstrates the potential of S. cerevisiae as a robust chassis for violacein biosynthesis via synthetic biology strategies. The combination of multicopy gene integration, targeted gene overexpression, and response surface optimization provides a scalable and safe platform for industrial production of violacein. Further improvement through metabolic engineering may bridge the gap toward full commercialization.