Preparation of immobilized NAD glycohydrolase from Neurospora crassa conidia by hydrophobic interaction--characteristics of the enzyme derivative.

NAD glycohydrolase from Neurospora crassa conidia has been immobilized by hydrophobic interaction on Sepharose 4B beads coated with propyl residues through CNBr activation. The bond resulted stable under a wide range of conditions (ionic strength, temperature, pH). As a result of immobilization the pH optimum for catalytic activity shifted by about 0.2 pH unit in the acidic direction, to lie between 7.5 and 7.3. The stability of the enzymatic activity was largely enhanced by effect of immobilization but the Km value towards NAD+ was increased compared with that of the free enzyme (1 X 10(-3) and 2 X 10(-4) M respectively).