大分子拥挤对酶蛋白及DNA的影响

Effect of macromolecular crowding on enzyme protein and DNA

大分子拥挤是指在蛋白质、多肽、核酸和多聚糖共同形成的环境中,由于大分子的不可穿透性,使任何一个大分子的实际可及空间大幅缩小,所形成的生物大分子环境是一种由于空间排斥引起的纯物理性非特异性效应。酶在机体中发挥高效专一的催化作用,细胞内分子环境改变可能导致酶活性的改变,影响细胞及机体的稳态,同时大分子拥挤还可能影响DNA的合成。本文主要从大分子拥挤对酶(包括酶蛋白性质、酶活性、酶蛋白最适温度)和DNA的影响及其可能的作用机制等方面作一综述。

Macromolecular crowding is caused by the remarkable reduction of practically achievable space of any macromolecule due to the impermeability of macromolecules in the environment formed by proteins,polypeptides,nucleic acids and polysaccharides,which is a ubiquitous physiological phenomenon caused by spatial exclusion. Since enzyme plays an effective and specific catalytic role in organism,the change of molecular environment may cause the change of enzyme activity,thus affects the steady-state of cell and organism. Meanwhile,macromolecular crowding may influence the DNA synthesis. This paper reviews the influence of macromolecular crowding on enzyme(including the property,activity and optimal temperature of enzyme)and DNA as well as the possible mechanism.