Three Redundant Synthetases Secure Redox-Active Pigment Production in the Basidiomycete Paxillus involutus.
The symbiotic fungus Paxillus involutus serves a critical role in maintaining forest ecosystems, which are carbon sinks of global importance. P. involutus produces involutin and other 2,5-diarylcyclopentenone pigments that presumably assist in the oxidative degradation of lignocellulose via Fenton chemistry. Their precise biosynthetic pathways, however, remain obscure. Using a combination of biochemical, genetic, and transcriptomic analyses, in addition to stable-isotope labeling with synthetic precursors, we show that atromentin is the key intermediate. Atromentin is made by tridomain synthetases of high similarity: InvA1, InvA2, and InvA5. An inactive atromentin synthetase, InvA3, gained activity after a domain swap that replaced its native thioesterase domain with that of InvA5. The found degree of multiplex biosynthetic capacity is unprecedented with fungi, and highlights the great importance of the metabolite for the producer.
Department of Pharmaceutical Microbiology, Hans Knöll Institute, Friedrich-Schiller-University Jena, Beutenbergstrasse 11a, 07745 Jena, Germany.
Jana
J
Braesel
Junior Group Chemistry of Microbial Communication, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Beutenbergstrasse 11a, 07745 Jena, Germany.
Sebastian
S
Götze
Department of Biology, Lund University, Sölvegatan 37, 221 00 Lund, Sweden.
Firoz
F
Shah
Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Beutenbergstrasse 11a, 07745 Jena, Germany.
Daniel
D
Heine
Department of Pharmaceutical Microbiology, Hans Knöll Institute, Friedrich-Schiller-University Jena, Beutenbergstrasse 11a, 07745 Jena, Germany.
James
J
Tauber
Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Beutenbergstrasse 11a, 07745 Jena, Germany.
Christian
C
Hertweck
Department of Biology, Lund University, Sölvegatan 37, 221 00 Lund, Sweden.
Anders
A
Tunlid
Junior Group Chemistry of Microbial Communication, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Beutenbergstrasse 11a, 07745 Jena, Germany.
Pierre
P
Stallforth
Department of Pharmaceutical Microbiology, Hans Knöll Institute, Friedrich-Schiller-University Jena, Beutenbergstrasse 11a, 07745 Jena, Germany. Electronic address: dirk.hoffmeister@hki-jena.de.
Dirk
D
Hoffmeister
D000595:Amino Acid Sequence; D001487:Basidiomycota / Q000201:enzymology* / Q000235:genetics; D002851:Chromatography, High Pressure Liquid; D003001:Cloning, Molecular; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D008025:Ligases / Q000235:genetics / Q000378:metabolism*; D013058:Mass Spectrometry; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010860:Pigments, Biological / Q000096:biosynthesis* / Q000235:genetics; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D013379:Substrate Specificity; D014158:Transcription, Genetic
D005656:Fungal Proteins; D010860:Pigments, Biological; D008025:Ligases
Paxillus; basidiomycete; gyrocyanin; involutin; pigment; secondary metabolism; synthetase