Post-genomic approach based discovery of alkylresorcinols from a cricket-associated fungus, Penicillium soppi

Abstract

A highly reducing polyketide synthase (HR-PKS) collaborates with a type III PKS to produce alkylresorcinols via unusual biosynthetic machinery.

Evolutionary Histories of Type III Polyketide Synthases in Fungi

“…All BGCs predicted by antiSMASH to contain a type III PKS of fungal origin were searched for reducing PKS sequences as characterized by the presence of either PF08659 (KR ketoreductase) or PF14765 (PS-DH dehydratase) domains; and the absence of any signature domain from non-reducing PKSs (either PF16073, SAT starter unit:ACP transacylase or TIGR04532, PT product template). This search produced a list of 46 sequences, which were complemented with all reducing PKS sequences from the MIBiG database, as well as the characterized PspA PKS (Kaneko et al, 2019), for a total of 110 sequences (Supplementary Material S3).…”

“…Apart from the soppiline BGC in P. soppi (Kaneko et al, 2019), only single type III PKSs have been characterized in fungi. In P. soppi, the BGC comprises a cytochrome P450 monooxygenase gene in addition to the two core type III and reducing PKS genes (Kaneko et al, 2019).…”

“…Apart from the soppiline BGC in P. soppi (Kaneko et al, 2019), only single type III PKSs have been characterized in fungi. In P. soppi, the BGC comprises a cytochrome P450 monooxygenase gene in addition to the two core type III and reducing PKS genes (Kaneko et al, 2019). As mentioned above in clades 7 and 8, fungal type III PKS genes are located at loci that comprise genes encoding diverse tailoring functions (Figure 5 and Supplementary Material S8).…”

“…A second route relies on type III PKSs, which are enzymes consisting of a single ketosynthase (KS) domain (Yu et al, 2012). While type I PKSs have been well characterized and found to be abundant in fungal genomes, only a handful of fungal type III PKSs have been characterized so far (Hashimoto et al, 2014;Sun et al, 2016;Ramakrishnan et al, 2018;Yan et al, 2018;Kaneko et al, 2019;Manoharan et al, 2019).…”

“…In A. oryzae, CsyB produces csypyrones from acetoacetyl-CoA starter unit and a ketoacyl diketide unit (Seshime et al, 2010a;Hashimoto et al, 2013;Mori et al, 2015). Recently, the type III PKS PspB from Penicillium soppi was shown to accept as starter unit an unsaturated linear polyketide produced by a reducing type I PKS, PspA, yielding the alkylresorcinol soppiline B (Kaneko et al, 2019). Type III PKSs can also accommodate long fatty acids as shown with SsArs which can use unsaturated fatty acids from soybean oil to produce 5-(8 Z,11 Z-heptadecadienyl)resorcinol (Yan et al, 2018).…”