二价生物分子的拥挤调控结合
Crowding-Regulated Binding of Divalent Biomolecules
AI总结:
本文结合标度粒子理论与分子模拟,研究拥挤对单价-二价生物分子结合的影响,发现拥挤可显著增强或减弱协同性,并能使原本不发生的结合得以实现,且对免疫球蛋白G与抗原的结合在体相和表面呈现相反调控效应。
摘要:
大分子拥挤影响多种生物物理过程,如扩散、基因表达、细胞生长和衰老。然而,目前对拥挤如何影响反应,尤其是多价结合,仍缺乏全面的理解。本文中,我们使用标度粒子理论并开发了一种分子模拟方法,以研究单价与二价生物分子的结合。我们发现,拥挤可以使协同性——即结合第一个分子后第二个分子的结合增强程度——提高或降低数个数量级,具体取决于所涉及分子复合物的大小。当二价分子在结合两个配体后先膨胀再收缩时,协同性通常会增强。我们的计算还揭示,在某些情况下,拥挤能够使原本不会发生的结合得以进行。作为免疫学实例,我们考虑了免疫球蛋白G与抗原的结合,并表明拥挤在体相中增强其协同性,但当免疫球蛋白G结合表面上的抗原时则会降低其协同性。
英文摘要:
Macromolecular crowding affects biophysical processes as diverse as diffusion, gene expression, cell growth, and senescence. Yet, there is no comprehensive understanding of how crowding affects reactions, particularly multivalent binding. Herein, we use scaled particle theory and develop a molecular simulation method to investigate the binding of monovalent to divalent biomolecules. We find that crowding can increase or reduce cooperativity--the extent to which the binding of a second molecule is enhanced after binding a first molecule--by orders of magnitude, depending on the sizes of the involved molecular complexes. Cooperativity generally increases when a divalent molecule swells and then shrinks upon binding two ligands. Our calculations also reveal that, in some cases, crowding enables binding that does not occur otherwise. As an immunological example, we consider Immunoglobulin G-antigen binding and show that crowding enhances its cooperativity in bulk but reduces it when an Immunoglobulin G binds antigens on a surface.
机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。