Non-reducing polyketide synthase; part of the pkg gene cluster that mediates the biosynthesis of dihydrocitreoisocoumarin and 6,8-dihydroxy-3-(2-oxopropyl)-isocoumarin (PubMed:22510154). The non-reducing polyketide synthase pkgA performs the condensation of one acetyl-CoA starter unit with 6 and 5 malonyl-CoA units, respectively (PubMed:22510154). As pkgA lacks a releasing domain, the thioesterase pkgB is necessary to break the thioester bond and release dihydrocitreoisocoumarin and 6,8-dihydroxy-3-(2-oxopropyl)-isocoumarin from pkgA (PubMed:22510154). acetyl-CoA + 6 H(+) + holo-[ACP] + 6 malonyl-CoA = 3,5,7,9,11,13-hexaoxotetradecanoyl-[ACP] + 6 CO2 + 7 CoA acetyl-CoA + 5 H(+) + holo-[ACP] + 5 malonyl-CoA = 3,5,7,9,11-pentaoxododecanoyl-[ACP] + 5 CO2 + 6 CoA Binds 1 phosphopantetheine covalently. 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.