The identified NPKs mutants demonstrated a reduction in the transcription, and capacity of, hydrolytic enzymes. The parental (WT), NPKs mutant strains were grown in MM plus 1% fructose overnight and then transferred to AVICEL or xylan as a sole carbon source for an additional 5 or 3 days, respectively. The endocellulase activity of the 5 day AVICEL culture (A). The relative expression of the major endoglucanase genes, eglA and eglB, in the mycelia isolated from the cultures used to determine endocellulase activity (B). The endoxylanase activity of the xylan cultures (C).