Regulation of Neurospora crassa nucleosidases by some environmental factors.

Enzymic cleavage of N-glycosidic bonds of AMP, GMP, and inosine by the cell-free extracts of Neurospora crassa has been studied. The enzymic activities with these substrates appear to be discrete from one another. The levels of these enzymes in the cell vary with age, and are dependent upon the inoculum size, aeration rate, and phosphate level in the medium. Glucose (or ribose) controls the phosphate-mediated repression of all the three nucleosidases of this fungus.