Cellular propionyl-CoA content in the wild-type, ΔmcsA, ΔpcsA, and ΔmcsA/ΔpcsA strains. The four strains used in this assay were FGSC26 (wild type), RYQ11 (ΔmcsA), TYQ4.24 (ΔpcsA), and RYQ25.1 (ΔmcsA/ΔpcsA). Propionyl-CoA was extracted from mycelia grown for 72 hr on 50 mm GMM. The propionyl-CoA content is significantly higher in the ΔmcsA strains than in the other three strains (P < 0.001). Three samples were taken for each strain. Standard error bars are shown.