| Summary: | Fungi from the <i>Hypocreales</i> order synthesize a range of toxic non-ribosomal cyclic peptides with antimicrobial, insecticidal and cytotoxic activities. Entomopathogenic <i>Beauveria</i>, <i>Isaria</i> and <i>Cordyceps</i> as well as phytopathogenic <i>Fusarium</i> spp. are known producers of beauvericins (BEAs), beauvenniatins (BEAEs) or enniatins (ENNs). The compounds are synthesized by beauvericin/enniatin synthase (BEAS/ESYN1), which shows significant sequence divergence among <i>Hypocreales</i> members. We investigated ENN, BEA and BEAE production among entomopathogenic (<i>Beauveria</i>, <i>Cordyceps</i>, <i>Isaria</i>) and phytopathogenic (<i>Fusarium</i>) fungi; BEA and ENNs were quantified using an LC-MS/MS method. Phylogenetic analysis of partial sequences of putative <i>BEAS</i>/<i>ESYN1</i> amplicons was also made. Nineteen fungal strains were identified based on sequence analysis of amplified ITS and <i>tef</i>-1α regions. BEA was produced by all investigated fungi, with <i>F. proliferatum</i> and <i>F. concentricum</i> being the most efficient producers. ENNs were synthesized mostly by <i>F. acuminatum</i>, <i>F. avenaceum</i> and <i>C. confragosa</i>. The phylogeny reconstruction suggests that ancestral BEA biosynthesis independently diverged into biosynthesis of other compounds. The divergent positioning of three <i>Fusarium</i> isolates raises the possibility of parallel acquisition of cyclic depsipeptide synthases in ancient complexes within <i>Fusarium</i> genus. Different fungi have independently evolved NRPS genes involved in depsipeptide biosynthesis, with functional adaptation towards biosynthesis of overlapping yet diversified metabolite profiles.
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