Non-reducing polyketide synthase; part of the gene cluster that mediates the biosynthesis of geodin, an intermediate in the biosynthesis of other natural products (PubMed:7665560, PubMed:19549600, PubMed:24009710). The pathway begins with the synthesis of atrochrysone thioester by the polyketide synthase (PKS) gedC (PubMed:12536215, PubMed:19549600). The atrochrysone carboxyl ACP thioesterase gedB then breaks the thioester bond and releases the atrochrysone carboxylic acid from gedC (PubMed:19549600). The atrochrysone carboxylic acid is then converted to atrochrysone which is further transformed into emodinanthrone (PubMed:24009710). The next step is performed by the emodinanthrone oxygenase gedH that catalyzes the oxidation of emodinanthrone to emodin (PubMed:1810248). Emodin O-methyltransferase encoded probably by gedA then catalyzes methylation of the 8-hydroxy group of emodin to form questin (PubMed:1444712). Ring cleavage of questin by questin oxidase gedK leads to desmethylsulochrin via several intermediates including questin epoxide (PubMed:3182756). Another methylation step probably catalyzed by methyltransferase gedG leads to the formation of sulochrin which is further converted to dihydrogeodin by the sulochrin halogenase gedL (PubMed:24009710). Finally, the dihydrogeodin oxidase gedJ catalyzes the stereospecific phenol oxidative coupling reaction converting dihydrogeodin to geodin (PubMed:7665560). 8 H(+) + holo-[ACP] + 8 malonyl-CoA = atrochrysone carboxyl-[ACP] + 8 CO2 + 8 CoA + 2 H2O Secondary metabolite biosynthesis. Multidomain protein; including a starter unit:ACP transacylase (SAT) that selects the starter unit; a ketosynthase (KS) that catalyzes repeated decarboxylative condensation to elongate the polyketide backbone; a malonyl-CoA:ACP transacylase (MAT) that selects and transfers the extender unit malonyl-CoA; a product template (PT) domain that controls the immediate cyclization regioselectivity of the reactive polyketide backbone; and an acyl-carrier protein (ACP) that serves as the tether of the growing and completed polyketide via its phosphopantetheinyl arm (By similarity). Impairs the production of geodin and of its intermediary metabolite sulochrin (PubMed:12536215, PubMed:15129726).