【摘要】 研究了温度对枯草芽抱杆菌86315 α-淀粉酶的活性和荧光光谱的影响.发现该酶在50℃以下是稳定的;70℃加热10 min,酶活性全部丧失,荧光光谱发生了较大的变化;在0.02 mol/LCaCl₂和0.02 mol/L NaCI同时存在下,70℃加热10 min,酶活性保持不变,其光谱接近天然态酶的荧光光谱.实验表明,一定比例的CaCl₂和NaCl能够较好地稳定α-淀粉酶的构象,从而大大提高其热稳定性。更多还原

【Abstract】 The thermal stability and the fluorescence spectra of α-amylase from bacillus subtilis 86315 are studied in this paper. The enzyme is stable below 50℃- Heated at 70℃ for 10 min the enzyme loses its all activity, at the same time, a considerable change of its fluorescence spectra was observed . The α-amylase in the solution including 0. 02 mol/L CaCl2 and 0. 02 mol/L NaCl retains its activity on heating at 70℃ for 10 min, and its fluorescence spectrum is close to that of the native enzyme. The experimental results show that a proper ratio of CaClz to NaCl could stabilize the conformation of a-amylase, thus raising its thermal stability greatly.更多还原