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酶类作为一种特殊蛋白质应用极广泛,但它们往往不耐热。目前公认的蛋白质热灭活过程为:经中等温度、短时间加热后,其分子发生可逆性伸展,而在较高温度、长时间加热后,则发生不可逆的灭活,这一过程可能包括蛋白的聚集、肽键的水解、天冬酰胶的脱酰胺基、伴有或不伴有二硫键互换反应及辅基解离的“杂乱”结构形成等。嗜热生物体内的酶具有高热稳定性,此种特性不取决于某单一因素,至今发现这些酶具有的独特特征为:更多的离子对形成、金属的结合、糖基化、表面精氨酸残基数增多、天冬氨酸和天冬酰胺残基数减少
Enzymes are extremely popular as a special protein, but they are often not thermolabile. The currently accepted process of protein heat inactivation is that, after being heated at a moderate temperature for a short period of time, its molecule reversibly stretches, and irreversibly inactivates at higher temperatures and for a long time after heating, and this process may include protein Aggregation, cleavage of peptide bonds, deamidation of asparagine, “disorganized” structure formation with or without disulfide bond exchange and exciption dissociation, and the like. Enzymes in thermophilic organisms are highly thermostable and do not depend on a single factor, so far these enzymes have been characterized by more ion pair formation, metal binding, glycosylation, surface arginine Increase in the number of residues, aspartic acid and asparagine residues decreased