Otimização da produção heteróloga de fenazina-1-ácido carboxílico por cepas recombinantes de Escherichia coli

Abstract

Phenazines are microbial secondary metabolites with promising applications as biopesticides, biosensors, and pharmaceuticals. However, current production processes remain inefficient and unsustainable, highlighting the need for alternative strategies. In this work, we optimized the heterologous production of phenazine-1-carboxylic acid (PCA) in recombinant Escherichia coli through metabolic engineering. Starting from an engineered E. coli strain that carries a plasmid for PCA expression, we evaluated the effects of overexpressing the genes aroD, aroE, tktA, and vhb50, alongside deletion of the regulatory gene tyrR. Shake flask experiments demonstrated that tyrR deletion alone increased PCA titers by 41%, while its combination with aroD or aroE overexpression raised production by 282% and 330%, respectively. Co-expression of tktA and vhb50 together with tyrR deletion enhanced PCA yields by 377%. The final engineered strain carrying all modifications achieved 209% higher PCA production in flasks and 274% in bioreactor batch cultivation, compared to the parental strain. These results demonstrate the potential of targeted metabolic engineering for efficient heterologous phenazine production in E. coli.