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利用差示手扫描量热法(DSC)研究了溶菌酶在不同浓度的添加剂(蔗糖、葡萄糖、果糖、甘露醇)和不同浓度的磷酸盐缓冲液影响下的热变性过程,并用等转化率法对该过程进行了分析.变性温度T_m随扫描速率和添加剂浓度的增加而提高,随磷酸盐缓冲液浓度的增加而降低.磷酸盐加速了溶菌酶的变性过程,降低了溶菌酶的热稳定性,而添加剂则增强了溶菌酶的热稳定性.在添加剂存在的条件下,溶菌酶变性过程部分为聚集不可逆过程,部分则可逆.等转化率法表明溶菌酶在所仃条件下,其表观活化能在不同的转化率下并未保持小变,而足随转化率增大而减小,说明了一个简单的反应机理并不能用米描述溶菌酶的变性过程,其过程并不是标准两态可逆过程,而是一个涉及多种蚩白质状态的复杂过程.“,”The thermal denaturation of lysozyme was studied as a function of different additive (sucrose, glucose, fructose, mannitol) concentrations, phosphate buffer concentration and scan rate using differential scanning calorimetry (DSC) and analyzed by an isoconversional method. The denaturation temperature T_m increased with the increase of scan rate and the additive concentrations, while decreased with the increase of phosphate concentration. The phosphate accelerated the denaturation process of lysozyme and reduced the thermal stability of lysozyme, while the additives enhanced it. One part of the lysozyme denaturation process was irreversible in which aggregation occurred, and the other part was reversible in the presence of all addi-tives. By the isoconversional method, it was showed that the apparent activation energy did not keep invari-able at different conversion ratios (a) under all conditions, but decreased with the increase of a, which sug-gested that a simple reaction mechanism could not be used for the denaturation process. The denaturation was still not a process involving the two standard reversible states, but a multi-step process in the presence and the absence of all additives.