Purification and characterization of Neurospora crassa N-acetyl galactosaminoglycan deacetylase.

1. N-Acetyl galactosaminoglycan deacetylase was purified from Neurospora mycelium 215-fold in 25% yield to electrophoretic homogeneity. A single band corresponding to a molecular weight of 76,000 was obtained by sodium dodecyl sulfate/polyacrylamide gel electrophoresis. 2. The enzyme activity had pH optima at pH 5.0 and 9.0. Sodium molybdate, 2 mM, stimulated enzyme activity 4-fold at pH 5.0 but had no effect at pH 9.0. Cupric ion, 1 mM, inhibited activity by more than 85% at pH 5.0 and 9.0. The Km of the enzymatic reactions was 16 microM on the basis of the concentration of N-acetylgalactosamine. 3. This enzyme may be involved in determining the properties of the hyphal apex of the colonial form of Neurospora crassa and thus could play a role in morphogenetic regulation.