Phloroglucinol functions as an intercellular chemical messenger with broad transcriptional effects in Pseudomonas protegens. Pseudomonas protegens

We demonstrate that phloroglucinol (PG), an intermediate in DAPG biosynthesis, can serve as an intercellular signal influencing the expression of pyoluteorin biosynthesis genes, the production of pyoluteorin, and inhibition of Pythium ultimum, a phytopathogenic oomycete sensitive to pyoluteorin. In addition, we show that phloroglucinol has broad effects on the transcriptome of Pf-5 with nanomolar versus micromolar concentrations of phloroglucinol having differential effects on the transcriptome. Overall design: RNA sequencing of Pseudomonas protegens Pf-5 wild-type, phlAG mutant, and phlADG mutant in the presence/absence of phloroglucinol.