FIG 3 .

GMI1000-conditioned medium and purified ralsolamycin induce bikaverin production in F. fujikuroi. (A) GMI1000-conditioned medium, but not ΔrmyA strain-conditioned medium, caused dramatic shifts in pigment production in both F. fujikuroi strains relative to medium controls. (B) HPLC-PDA analysis of liquid cultures of F. fujikuroi treated with GMI1000-conditioned medium shows significantly increased bikaverin production under both high- and low-nitrogen conditions. (C) Semiquantitative reverse transcription-PCR shows that bikaverin biosynthetic genes bik1, bik2, and bik3 in F. fujikuroi are induced in response to GMI1000-conditioned medium but not in response to ΔrmyA strain-conditioned medium or bacterial medium controls. Actin was used as a loading control. (D) Purified ralsolamycin induces bikaverin production in F. fujikuroi which was quantified by HPLC from seven biological replicates. Acetonitrile was used as the carrier control. (E) Northern analysis showing induction of bikaverin biosynthetic genes (technical duplicates) in response to purified ralsolamycin.