Analysis of 21 Apiospora genomes reveals a genus with tremendous synthesis potential for carbohydrate-active enzymes and secondary metabolites

The genus Apiospora has been relatively understudied in comparison to other filamentous fungi species, despite indications from previous research that this genus could yield valuable discoveries of novel enzymes and secondary metabolites applicable to various practical uses. In this investigation, we conducted sequencing of 16 previously uncharacterized Apiospora genomes. Seven are distantly related to previously known genomes and are the first genome assembly available for these species. In conjunction with five existing genome assemblies, we conducted an examination of the genetic composition and diversity within this genus. A deeper analysis of the genomes revealed a genus rich in genes associated with carbohydrate-active enzymes (CAZymes) and secondary metabolites. We identified the synthesis potential of CAZymes to be a core genome feature of the genus. In addition, clustering of polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) core genes into gene families, revealed a highly diverse specialized metabolite synthesis potential within the genus. Surprisingly, we also found that certain Apiospora species completely lack the gene cluster responsible for the synthesis of 3-nitropropionic acid (3-NPA), a compound previously associated with this genus. Taken together, this study’s results elucidate an unusually high potential for the discovery of new enzymes and compounds within the Apiospora genus.