Production of Antifungal p-Aminobenzoic Acid in Lysobacter antibioticus OH13

Among Lysobacter species, Lysobacter antibioticus has been demonstrated to be an interesting source of antimicrobial metabolites for the biocontrol of plant diseases. Although the antibacterial activity was attributed to N-oxide phenazines, the active compounds involved in the antifungal function remained unknown. In this work, an antifungal compound was isolated and identified as p-aminobenzoic acid (pABA). Antifungal activity screening revealed that pABA shows activity against a number of plant pathogens. The genes involved in the synthetic route of this compound in OH13 were identified. Further, the production of pABA was optimized by modification of the carbon source using engineered L. antibioticus OH13 strains.