Genome Mining and Comparative Biosynthesis of Meroterpenoids from Two Phylogenetically Distinct Fungi

Abstract

Two homologous meroterpenoid gene clusters consisting of contiguous genes encoding polyketide synthase (PKS), prenyltransferase (PT), terpenoid cyclase (TC) and other tailoring enzymes were identified from two phylogenetically distinct fungi through computational analysis. Media optimization guided by reverse-transcription PCR (RT-PCR) enabled two strains to produce eight new and two known meroterpenoids (1-10). Using gene inactivation, heterologous expression, and biochemical analyses, we revealed a new polyketide-terpenoid assembly line that utilizes a pair of PKSs to synthesize 2,4-dihydroxy-6-alkylbenzoic acid, followed by oxidative decarboxylation, farnesyl transfer, and terpene cyclization to construct the meroterpenoid scaffold. In addition, two of the isolated meroterpenoids (3 and 17 d) showed immunosuppressive bioactivity. Our work reveals a new strategy for meroterpenoid natural products discovery, and reveals the biosynthetic pathway for compounds 1-10.

Exploiting the Biosynthetic Potency of Taxol from Fungal Endophytes of Conifers Plants; Genome Mining and Metabolic Manipulation

“…So, these computational tools provide a culture-independent route to find new secondary metabolites where traditional laboratory-based approaches fail. Thus, integrating computational and experimental technologies together into a comparative platform that can address large-scale natural product characterization projects will enable further exploration of the natural products [ 153 ]. With the development of high-throughput sequencing and computational analysis, genome sequence-based mining approaches could be summarized according to their evolutionary records in the following; (1) Classical genome mining, (2) Comparative genome mining, (3) Phylogeny based genome mining, (4) Resistance/target based genome mining, (5) Metagenome mining, (6) single cell genome mining [ 154 ].…”

Comparative genome mining and heterologous expression of an orphan NRPS gene cluster direct the production of ashimides

“…According to this rule, the amino acid building block composition of NRPs can correlate well with their corresponding NRPS architectures 6,7. With the massive accumulation of bacterial genome data, it has become obvious that the biosynthetic potential of NRPs greatly exceeds the number of compounds that have been isolated 8,9. Orphan gene clusters, which are gene loci to which no known homologous gene clusters can be found, represent a particularly rich and untapped source for novel natural product discovery.…”

“… 6 , 7 With the massive accumulation of bacterial genome data, it has become obvious that the biosynthetic potential of NRPs greatly exceeds the number of compounds that have been isolated. 8 , 9 Orphan gene clusters, which are gene loci to which no known homologous gene clusters can be found, represent a particularly rich and untapped source for novel natural product discovery. Genome mining targeting the orphan NRPS gene cluster is therefore a powerful approach to discover novel NRPs.…”

Pyridoxal-5′-phosphate–dependent bifunctional enzyme catalyzed biosynthesis of indolizidine alkaloids in fungi

“…As an efficient way of obtaining new bioactive natural products, the genome mining effort can be facilitated by the BGC organization of almost all types of compounds such as meroterpenoids (45). This strategy enables as well the characterization of structurally diverse secondary metabolites encoded by orphan and neglected biosynthetic gene clusters (46).…”