Enzymatic synthesis of bis-5-alkylresorcinols by resorcinol-producing type III polyketide synthases.

No enzyme systems responsible for the biosynthesis of structurally and biosynthetically intriguing bis-5-alkylresorcinols produced by plants have been identified. Herein, we show that bacterial, fungal and plant alkylresorcinol-producing type III polyketide synthases (PKSs), such as ArsB in the Gram-negative bacterium Azotobacter vinelandii, ORAS in the fungus Neurospora crassa and ARAS2 in the rice plant Oryza sativa, can synthesize bis-5-alkylresorcinol from alkanedioic acid N-acetylcysteamine dithioester as a starter substrate and from malonyl-CoA as an extender substrate by two-step conversion. Plants presumably use a type III PKS for the biosynthesis of bis-5-alkylresorcinols.