ABSTRACT
By mining fungal genomic information, a noncanonical iterative type I PKS fused with an N-terminal adenylation-thiolation didomain, which catalyzes the formation of naringenin chalcone, was found. Structural prediction and molecular docking analysis indicated that a C-terminal thioesterase domain was involved in the Claisen-type cyclization. An enzyme responsible for formation of (2S)-flavanone in the biosynthesis of fungal flavonoids was also identified. Collectively, these findings demonstrate unprecedented fungal biosynthetic machinery leading to plant-like metabolites.
Subject(s)
Acyltransferases , Flavonoids , Molecular Docking Simulation , Flavonoids/chemistryABSTRACT
Genome mining and bioinformatics analyses allowed us to rationally find a candidate biosynthetic gene cluster for a new cyclic depsipeptide of Chaetomium mollipilium. A heterologous reconstitution of the identified biosynthetic pathway predictably afforded a new cyclic depsipeptide composed of l-leucine, l-tryptophan, and a polyketide moiety. Interestingly, the 10-membered macrocycle structure generated equilibrium to an unprecedented cyclol structure. This study demonstrates the advantage of a synthetic biology method in achieving rational access to new natural products.
Subject(s)
Biological Products , Chaetomium , Depsipeptides , Polyketides , Biological Products/chemistry , Biosynthetic Pathways , Chaetomium/genetics , Depsipeptides/chemistry , Multigene Family , Polyketides/chemistryABSTRACT
Diterpenoid pyrones are a type of mainly fungal meroterpenoid metabolite consisting of a diterpene connected to a pyrone, some of which show potent bioactivity. Through genome mining and heterologous expression, nine new diterpenoid pyrones, shearones A-I (1-9), were discovered from the fungus Eupenicillium shearii IFM 42152, and their biosynthetic enzyme activities were revealed. Some of these heterologously biosynthesized diterpenoid pyrones exhibited moderate antiaggregative ability against amyloid ß42 in vitro.
Subject(s)
Diterpenes , Pyrones , Diterpenes/metabolism , Diterpenes/pharmacology , Penicillium , Pyrones/pharmacology , Synthetic BiologyABSTRACT
A synthetic biology method based on heterologous biosynthesis coupled with genome mining is a promising approach for increasing the opportunities to rationally access natural product with novel structures and biological activities through total biosynthesis and combinatorial biosynthesis. Here, we demonstrate the advantage of the synthetic biology method to explore biological activity-related chemical space through the comprehensive heterologous biosynthesis of fungal decalin-containing diterpenoid pyrones (DDPs). Genome mining reveals putative DDP biosynthetic gene clusters distributed in five fungal genera. In addition, we design extended DDP pathways by combinatorial biosynthesis. In total, ten DDP pathways, including five native pathways, four extended pathways and one shunt pathway, are heterologously reconstituted in a genetically tractable heterologous host, Aspergillus oryzae, resulting in the production of 22 DDPs, including 15 new analogues. We also demonstrate the advantage of expanding the diversity of DDPs to probe various bioactive molecules through a wide range of biological evaluations.
Subject(s)
Diterpenes/pharmacology , Fungi/chemistry , Naphthalenes/pharmacology , Pyrones/pharmacology , Synthetic Biology , Amyloid beta-Peptides/metabolism , Animals , Anti-HIV Agents/pharmacology , Aspergillus/chemistry , Biosynthetic Pathways/drug effects , Biosynthetic Pathways/genetics , Cell Proliferation/drug effects , Diterpenes/chemistry , Drosophila/drug effects , Fungi/genetics , Genome, Fungal , HIV-1/drug effects , Humans , MCF-7 Cells , Naphthalenes/chemistry , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Protein Aggregates , Pyrones/chemistry , Spheroids, Cellular/drug effects , Spheroids, Cellular/metabolism , Spheroids, Cellular/pathology , StereoisomerismABSTRACT
Polyketide synthase (PKS) gene-guided genome mining in a cricket-associated fungus, Penicillium soppi, revealed a cryptic biosynthetic gene cluster that contained a highly reducing PKS (HR-PKS), a type III PKS, and a P450 gene. Heterologous expression of the cluster in Aspergillus oryzae led to the isolation of novel alkylresorcinols with a unique Z,E,Z-triene motif. This study displays an unusual biosynthetic mechanism of an HR-PKS and a new releasing mechanism via a type III PKS in fungi.
Subject(s)
Drug Discovery , Enzyme Inhibitors/pharmacology , Penicillium/chemistry , Polyketide Synthases/antagonists & inhibitors , Resorcinols/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/isolation & purification , Molecular Structure , Polyketide Synthases/metabolism , Resorcinols/chemistry , Resorcinols/isolation & purificationABSTRACT
The structural complexity and diversity of natural products make them attractive sources for potential drug discovery, with their characteristics being derived from the multi-step combination of enzymatic and non-enzymatic conversions of intermediates in each biosynthetic pathway. Intermediates that exhibit multipotent behaviour have great potential for use as starting points in diversity-oriented synthesis. Inspired by the biosynthetic pathways that form complex metabolites from simple intermediates, we developed a semi-synthetic process that combines heterologous biosynthesis and artificial diversification. The heterologous biosynthesis of fungal polyketide intermediates led to the isolation of novel oligomers and provided evidence for ortho-quinonemethide equivalency in their isochromene form. The intrinsic reactivity of the isochromene polyketide enabled us to access various new chemical entities by modifying and remodelling the polyketide core and through coupling with indole molecules. We thus succeeded in generating exceptionally diverse pseudo-natural polyketides through this process and demonstrated an advanced method of using biosynthetic intermediates.