Researchers studied how Aspergillus oryzae fungi make ergosterol, a key ingredient in fungal cell membranes. They found that this process is much more complex in this mold than in baker’s yeast, with 49 genes involved. By selectively increasing expression of specific genes, they were able to boost ergosterol production by up to 2.3 times, which could have applications in producing fungal-derived medicines and improving fermented foods.