Biocatalytic potential of Pseudolycoriella CAZymes (Sciaroidea, Diptera) in degrading plant and fungal cell wall polysaccharides

Soil biota has a crucial impact on soil ecology, global climate changes, and effective crop management and studying the diverse ecological roles of dipteran larvae deepens the understanding of soil food webs. A multi-omics study of Pseudolycoriella hygida comb. nov. (Diptera: Sciaroidea: Sciaridae) aimed to characterize carbohydrate-active enzymes (CAZymes) for litter degradation in this species. Manual curation of 17,881 predicted proteins in the Psl. hygida genome identified 137 secreted CAZymes, of which 33 are present in the saliva proteome, and broadly confirmed by saliva CAZyme catalytic profiling against plant cell wall polysaccharides and pNP-glycosyl substrates. Comparisons with two other sciarid species and the outgroup Lucilia cuprina (Diptera: Calliphoridae) identified 42 CAZyme families defining a sciarid CAZyme profile. The litter-degrading potential of sciarids corroborates their significant role as decomposers, yields insights to the evolution of insect feeding habits, and highlights the importance of insects as a source of biotechnologically relevant enzymes. [Display omitted] •The Pseudolycoriella genome (609 Mb) encodes 17881 genes and 1022 CAZymes•The saliva proteome includes 33 of the 137 predicted secreted CAZymes•Diverse saliva CAZyme activities detected on polysaccharides and synthetic substrates•Comparison with other sciarids shows a rich conserved repertoire of secreted CAZymes Mycology; Biocatalysis; Plant biology