Characterization of the Cubamyces Menziesii Terpenome

The genome of Cubamyces menziesii reveals 18 putative sesquiterpene cyclase genes. These genes are cloned and expressed in Escherichia coli, yielding 10 active enzymes. Using farnesyl diphosphate as substrate, the enzymes are analyzed, and the products characterized after bioconversion, uncovering diverse sesquiterpene structures. This study highlights the phylogenetic prediction and the ecological and biotechnological relevance of C. menziesii sesquiterpenes.

Long-lasting polypore fungi are significant producers of terpene cyclases of high interest for medicinal or biotechnological applications. Following the 1000 Fungal Genomes initiative launched by the Joint Genome Institute, the genome of Cubamyces (C.) menziesii and identified 18 genes encoding sesquiterpene cyclases (STCs) is explored. In a search for robust catalysts suitable for practical applications, the 18 codon-optimized open reading frames are cloned and overproduced the C. menziesii STCs in Escherichia coli. In ten cases, the catalytically active enzyme is purified and tested with three chemically synthesized linear diphosphates: geranyl diphosphate, farnesyl diphosphate (FDP), and geranylgeranyl diphosphate. Only FDP proved to be a substrate for these 10 enzymes. The product specificity of all these enzymes is determined by (GC-MS) gas chromatography mass spectrometry and (NMR) nuclear magnetic resonance analysis. Among the 10 enzymes, four produced a predominant compound, four yielded two main compounds, and the remaining two acted as a multiproduct catalysts. This work sheds light on the potential sesquiterpenes involved in the chemical ecology of the polypore C. menziesii and provides evidence for the potential of Polyporales fungi in the identification of new sesquiterpene cyclase activities.

Zum Volltext