Catalyzes the reversible decarboxylation of aromatic carboxylic acids (Probable). Attenuates the virulence of P.aeruginosa in a Drosophila model when overexpressed (PubMed:18591226). Binds 1 prenylated FMN (prenyl-FMN) per subunit. Homodimer. Repressed by hudR. Belongs to the UbiD family. UbiD-like/FDC subfamily.