两种真菌的木聚精酶的催化性质研究

On Catalytic Characteristic of the Xylanases from Two Species of Fungi

通过硫酸铵分级盐析、透析和聚乙二醇浓缩，从两株串珠镰孢菌的菌丝滤液中制备了木聚糖酶，测定了该酶部分动力学性质，并与用相同方法制备的黑曲霉木聚糖酶作了比较．

Xylanases were prepared from culture filtrate of two variants of fungi Fusarium monilifomae by sblective preparation of protein with ammonium sulfate, and condensation with polyethylene glycol 6000 and dialysis. Some of the kinetic properties of the enzyme were detected and compared with thosie of xylanase prepared from Aspergillus niger. For Fusarium monilifomae, Km of 4 kinds of the enzymes. F11, F12, F21 and F22 are 2. 77, 0. 87, 2. 23 mmol/L, and 2. 06 mmol/L respectively. optimal PH is 45-60℃. The enzymes lost almost its activity under heat preservation at 70℃ for 1h or at 100℃ for 5min. Hg2+ can strongly inhibit the enzyme Mn2+ and Cu2+ of 1 mmol/L show some inhibition of xylanase, but Mg2+ gives stimulation, Mn2+ and Fe2+ of 0. 1 mmol/L improve the activity of the enzyme.