The chloride ion is an environmental factor affecting the biosynthesis of pyoluteorin and 2,4-diacetylphloroglucinol in Pseudomonas sp. YGJ3.

The effects of Cl(-) on the antibiotics productivity of Pseudomonas sp. YGJ3 were investigated. YGJ3 produced pyoluteorin and 2,4-diacetylphloroglucinol, depending on the concentration of Cl(-) in the culture medium. Cl(-) stimulated the biosynthesis of pyoluteorin, thereby repressing 2,4-diacetylphloroglucinol biosynthesis. The cell-free extract from the bacteria grown without Cl(-) showed high activity of monoacetylphloroglucinol acetyltransferase, an essential enzyme in 2,4-diacetylphloroglucinol biosynthesis.