title: Fungal biosynthesis of the bibenzoquinone oosporein to evade insect immunity.
abstract: 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 putative dioxygenase OpS7. The latter is further dimerized to oosporein by the catalase OpS5. The transcription factor OpS3 regulates intrapathway gene expression. Insect bioassays revealed that oosporein is required for fungal virulence and acts by evading host immunity to facilitate fungal multiplication in insects. These results contribute to the known mechanisms of quinone biosynthesis and the understanding of small molecules deployed by fungi that interact with their hosts.
authors: Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
authors: Peng
authors: P
authors: Feng
authors: Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
authors: Yanfang
authors: Y
authors: Shang
authors: Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
authors: Kai
authors: K
authors: Cen
authors: Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China cswang@sibs.ac.cn.
authors: Chengshu
authors: http://orcid.org/0000-0003-1477-1466
authors: C
authors: Wang
mesh_terms: D000818:Animals; D001483:Base Sequence; D052982:Beauveria / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D016227:Benzoquinones / Q000032:analysis / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D023061:Gene Order; D054884:Host-Pathogen Interactions / Q000276:immunology; D057131:Immune Evasion / Q000276:immunology; D007527:Isoenzymes / Q000145:classification / Q000235:genetics / Q000378:metabolism; D007814:Larva / Q000276:immunology / Q000382:microbiology; D009036:Moths / Q000276:immunology / Q000382:microbiology; D005810:Multigene Family / Q000235:genetics; D009154:Mutation; D009183:Mycotoxins / Q000032:analysis / Q000096:biosynthesis; D010802:Phylogeny; D048630:Polyketide Synthases / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D012689:Sequence Homology, Nucleic Acid; D053719:Tandem Mass Spectrometry; D014774:Virulence / Q000235:genetics / Q000276:immunology
chemical_list: D016227:Benzoquinones; D005656:Fungal Proteins; D007527:Isoenzymes; D009183:Mycotoxins; C008706:oosporein; D048630:Polyketide Synthases
keywords: Beauveria bassiana; bibenzoquinone; biosynthesis; oosporein; virulence