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DAHP synthase catalyzes the first step in the shikimate pathway, deriving the biosynthesis of aromatic amino acids (Trp, Phe and Tyr), phenazine-1-carboxamide, folic acid, and ubiquinone in <i>Pseudomonas chlororaphis</i>. In this study, we identified and characterized one DAHP synthase encoding gene <i>phzC</i>, which differs from the reported DAHP synthase encoding genes <i>aroF</i>, <i>aroG</i> and <i>aroH</i> in <i>E</i>. <i>coli</i>. PhzC accounts for approximately 90% of the total DAHP synthase activities in <i>P</i>. <i>chlororaphis</i> HT66 and plays the most critical role in four DAHP synthases in the shikimate pathway. Inactivation of <i>phzC</i> resulted in the reduction of PCN production by more than 90%, while the absence of genes <i>aroF</i>, <i>aroG</i> and <i>aroH</i> reduced PCN yield by less than 15%, and the production of PCN was restored after the complementation of gene <i>phzC</i>. Moreover, the results showed that <i>phzC</i> in <i>P</i>. <i>chlororaphis</i> HT66 is not sensitive to feedback inhibition. This study demonstrated that gene <i>phzC</i> is essential for PCN biosynthesis. The expression level of both <i>phzC</i> and <i>phzE</i> genes are not inhibited in feedback by PCN production due to the absence of a loop region required for allosteric control reaction. This study highlighted the importance of PhzC and applying <i>P</i>. <i>chlororaphis</i> for shikimate pathway-derived high-value biological production.