2,4-Diacetylphloroglucinol
2,4-Diacetylphloroglucinol is a natural phenol found in specific strains of the Gram-negative bacterium Pseudomonas fluorescens. This compound is found to be responsible for the antiphytopathogenic and biocontrol properties in these strains. It is also found in Pseudomonas protegens, where it has the same activity against various plant pathogens.
2,4-Diacetylphloroglucinol is also produced by Lysobacter gummosus, a bacterium which lives on the skin of red-backed salamanders.