Section-level genome sequencing and comparative genomics of sections and .

The genus is diverse, including species of industrial importance, human pathogens, plant pests, and model organisms. includes species from sections and , which until recently were joined in section , but have now been proposed to be non-monophyletic and were split by section and . To learn more about these sections, we have sequenced the genomes of 13 species from section (, and ), section ( and ), and section (, previously ). We compared these genomes with 16 additional species from to explore their genetic diversity, based on their genome content, repeat-induced point mutations (RIPs), transposable elements, carbohydrate-active enzyme (CAZyme) profile, growth on plant polysaccharides, and secondary metabolite gene clusters (SMGCs). All analyses support the split of section and provide additional insights: Analyses of genes found only in single species show that these constitute genes which appear to be involved in adaptation to new carbon sources, regulation to fit new niches, and bioactive compounds for competitive advantages, suggesting that these support species differentiation in species. Sections and have mainly unique SMGCs. Section contains very large and information-rich genomes, an expansion partially driven by CAZymes, as section contains the most CAZyme-rich species seen in genus . Section is clearly an underutilized source of plant biomass degraders and shows great potential as industrial enzyme producers. Nybo JL, Vesth TC, Theobald S, Frisvad JC, Larsen TO, Kjaerboelling I, Rothschild-Mancinelli K, Lyhne EK, Barry K, Clum A, Yoshinaga Y, Ledsgaard L, Daum C, Lipzen A, Kuo A, Riley R, Mondo S, LaButti K, Haridas S, Pangalinan J, Salamov AA, Simmons BA, Magnuson JK, Chen J, Drula E, Henrissat B, Wiebenga A, Lubbers RJM, Müller A, dos Santos Gomes AC, Mäkelä MR, Stajich JE, Grigoriev IV, Mortensen UH, de Vries RP, Baker SE, Andersen MR (2025). Section-level genome sequencing and comparative genomics of sections and . : 101-114. doi: 10.3114/sim.2025.111.03.