Aspergillus oryzae Compared to A. flavus - Genetic Analysis in Silico

Abstract

Two genetically close filamentous Aspergillus species, the non-toxic A. oryzae used for food fermentation for thousands of years (e.g., koji mold, sake, soy sauce) playing huge role in food industry, and the main aflatoxin producer of A. flavus are studied here based on genetic analysis in silico. The evolutionary TimeLine computer program of Ascomycota fungi showed 520 MYA origins. Phylogenetic tree of genome sequences of Ascomycota fungi was found to group in three main clades. The genome size of A. flavus (37.7 x106 bpDNA) but not A. sojae (41.1 x106 bpDNA) showed smaller size than the descendent (90-100 MYA) A. oryzae (37.9 x106 bpDNA). In phylogeny of mitogenomes (mtDNA) A. terreus showed a distinct clade, and the toxic A. parasiticus grouped to the non-toxic A. sojae. Fungal production of aflatoxins, cellulases, and the ribosomal post-translationally modified peptides (RiPPs) of nisin, asperigimycin, gliotoxin; the fungal non-ribosomal peptide (NRPs) fusahexin; the polyketide taxane and mycolactone are reviewed and discussed.