聚丙烯腈纤维固定化青霉素酰化酶性质的研究

将巨大芽孢杆菌（Bacillusmegaterium）青霉素酞化酶连接到聚丙烯腈纤维载体上，制成固定化青霉素酰化酶。其表现活力约为2000u／g。水解青霉素G的最适温度为50℃；最适PH为9．0；在PHS．5～10．3、温度50℃以下酶的活力稳定；表观米氏常数Ka为1．33×10-8mol／L；最大反应速度Vm为2．564mmol·min-1；苯乙酸为竞争性抑制剂，抑制常数为0．16mol／L。水解10％的青霉素G钾盐溶液，使用20批，保留酶活力80％。

STUDIES ON SOME PROPERTIES OF THE IMMOBILIZED PENICILLIN ACYLASE BY POLYACRYLONITRILE FIBRES

The extracellular penicillin acylase from Bacillus megaterium was immobilized by coupling to derivatives of polyacrylonitrile fibres. The apparent activity of the immobilized penicillin acylase was about 2,000 u/g (dry weight). The optimal pH and temperature were 9.0 and 50 degrees C for hydrolysis of penicillin G, respectively. The immobilized enzyme was stable in the pH range of 5.5-10.3, and at the temperature below 50 degrees C. The apparent Michaelis constant Ka and Vm of the immobilization enzyme were 1.33 x 10(-2) mol/L and 2.564 mmol.min-1, respectively. The inhibition constant of phenylacetic acid acted as a competitive inhibitor for The immobilization enzyme was 0.16 mol/L. The remained activity was about 80% after operating 20 times.