biostudies-literatureFeng PChinese Academy of SciencesNational Natural Science Foundation of China11365-70https://www.ebi.ac.uk/biostudies/studies/S-EPMC4568701biostudies-literatureUnknown112(36)Quinones are widely distributed in nature and exhibit diverse biological or pharmacological activities; however, their biosynthetic machineries are largely unknown. The bibenzoquinone oosporein was first identified from the ascomycete insect pathogen Beauveria bassiana>50 y ago. The toxin can also be produced by different plant pathogenic and endophytic fungi with an array of biological activities. Here, we report the oosporein biosynthetic machinery in fungi, a polyketide synthase (PKS) pathway including seven genes for quinone biosynthesis. The PKS oosporein synthase 1 (OpS1) produces orsellinic acid that is hydroxylated to benzenetriol by the hydroxylase OpS4. The intermediate is oxidized either nonenzymatically to 5,5'-dideoxy-oosporein or enzymatically to benzenetetrol by the putativeProceedings of the National Academy of Sciences of the United States of AmericaFungal biosynthesis of the bibenzoquinone oosporein to evade insect immunity.PMC456870131225023XDB11030100KSZD-EW-Z-021-2-4Wang CCen KShang YFeng PfalseFungal biosynthesis of the bibenzoquinone oosporein to evade insect immunity.Quinones are widely distributed in nature and exhibit diverse biological or pharmacological activities; however, their biosynthetic machineries are largely unknown. The bibenzoquinone oosporein was first identified from the ascomycete insect pathogen Beauveria bassiana>50 y ago. The toxin can also be produced by different plant pathogenic and endophytic fungi with an array of biological activities. Here, we report the oosporein biosynthetic machinery in fungi, a polyketide synthase (PKS) pathway including seven genes for quinone biosynthesis. The PKS oosporein synthase 1 (OpS1) produces orsellinic acid that is hydroxylated to benzenetriol by the hydroxylase OpS4. The intermediate is oxidized either nonenzymatically to 5,5'-dideoxy-oosporein or enzymatically to benzenetetrol by the putative2015-01-01T00:00:00Z2015 Sep2026-05-05T00:47:13.826Z2019-03-27T01:58:18ZS-EPMC45687012630593210.1073/pnas.1503200112