【作者】 于静波；

【导师】 贾绍义；

【作者基本信息】 天津大学 ， 化学工程， 2009， 硕士

【摘要】 为了探究磁场对酶的影响,本文选取脂肪酶和纤维素酶为研究对象,在不同磁场强度的永磁场中,对目标酶系进行磁化处理,然后从酶的活性、构象、酶促反应动力学、活化能和pH影响等几方面进行考察。研究结果表明,外加磁场对不同的酶会产生不同的影响。对于脂肪酶,磁化后,酶的活性增加比较明显;脂肪酶的米氏常数在磁场的影响下,Km变化不明显,Vm略有增大;磁化后的脂肪酶的活化能变化不大,说明反应速率对温度的敏感性受磁场影响不大;在本实验中pH值为7时为最佳磁化pH;在磁场的影响下,脂肪酶构象的二级结构发生了明显的改变。对于纤维素酶,磁化后,酶的活性增加非常明显;纤维素酶的米氏常数在磁场的影响下,Km和Vm都有增大;磁化后的纤维素酶的活化能变化很小,说明反应速率对温度的敏感性受磁场影响很小;在本实验中pH值为4时为最佳磁化pH;在磁场的影响下,纤维素酶构象的二级结构也发生了明显的改变。此外,磁场对某个酶的影响并不是呈简单的线性关系,即随着磁场强度的增大,对酶的影响并不是线性增加。本文分别对不同磁场强度下酶促反应动力学的实验数据进行了拟合,得到各个酶的米氏常数,并对拟合结果进行了检验。本文针对所研究的物系,从生物磁学的基本理论出发,对磁场影响酶的机理进行了探讨。认为磁场主要是通过影响酶的结构,从而影响酶促反应,并以此为依据,对实验结果进行了分析。更多还原

【Abstract】 In this paper, in order to investigate the influence of the magnetic field on enzyme, lipase and cellulase were studied under the various intensity static magnetic fields which were 0.15T, 0.30T and 0.45T. The enzyme was set in the magnetic field and then the enzyme activity, conformation, enzymatic reactions, activation energy and the influence of pH were investigated. The results showed that there were different effects of magnetic field due to the various enzyme values. For the lipase, the activity was obviously improved by the magnetic field, the value of Km was not very obvious change but Vm was enhanced. The change of activation energy between the magnetically treated and the control was not very obvious. It showed that the reaction rate on the temperature sensitivity was not affected by the magnetic field. The best pH of magnetization was 7 under the experimental condition. The secondary structure of lipase conformation which was detected by the CD(Circular dichroism) was changed after magnetization. For the cellulase, the activity was very obviously improved by the magnetic field; the value of Km and Vm were both improved. The change of activation energy was not very obvious between the magnetically treated and the control. The reaction rate on the temperature sensitivity is not affected by magnetic field. The best pH of magnetization was 4 under the experimental condition. The secondary structure of cellulase conformation which was detected by the CD was changed after magnetization. Besides, the relationship between effects of magnetic field and enzyme was not linear.In this study, the data of experiments were simulated by the Michaelis-Menton Equation, Km and Vm were obtained from the Michaelis-Menton Equation under the various of magnetic induction intensity. We also checked up the results of the simulation.Based on the basic bio-magnetic theory and the results of the experiments, the mechanism of the influence of magnetic field on enzyme was discussed. It was considered that the magnetic field influenced the enzyme by changing the enzyme conformation. The experimental phenomena were explained by this theory.更多还原