Pyoluteorin is a natural antibiotic that is biosynthesized from a hybrid nonribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) pathway.

[1] Pyoluteorin was first isolated in the 1950s from Pseudomonas aeruginosa strains T359 and IFO 3455[2] and was found to be toxic against oomycetes, bacteria, fungi, and against certain plants.

[3] Pyoluteorin is most notable for its toxicity against the oomycete Pythium ultimum,[4] which is a plant pathogen that causes a global loss in agriculture.

Currently, pyoluteorin derivatives are being studied as an Mcl-1 antagonist in order to target cancers that have elevated Mcl-1 levels.

[8] Pyoluteorin biosynthesis begins with the activation of L-proline to prolyl-AMP by the adenylation domain PltF.