, A Global Regulatory Gene, is Required for Pyrrolnitrin but not for Phenazine-1-carboxylic Acid Biosynthesis in G05.

In our previous study, pyrrolnitrin produced in G05 plays more critical role in suppression of mycelial growth of some fungal pathogens that cause plant diseases in agriculture. Although some regulators for pyrrolnitrin biosynthesis were identified, the pyrrolnitrin regulation pathway was not fully constructed. During our screening novel regulator candidates, we obtained a white conjugant G05W02 while transposon mutagenesis was carried out between a fusion mutant G05ΔΔ:: and S17-1 (pUT/mini-Tn5Kan).

LasR Might Act as an Intermediate in Overproduction of Phenazines in the Absence of RpoS in .

As an opportunistic bacterial pathogen, PAO1 contains two phenazineproducing gene operons, () and (), each of which is independently capable of encoding all enzymes for biosynthesizing phenazines, including phenazine-1-carboxylic acid and its derivatives. Other previous study reported that the RpoS-deficient mutant SS24 overproduced pyocyanin, a derivative of phenazine-1- carboxylic acid. However, it is not known how RpoS mediates the expression of two operons and regulates pyocyanin biosynthesis in detail.