Effects of Weak Nonspecific Interactions with ATP on Proteins
Effects of Weak Nonspecific Interactions with ATP on Proteins
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与 ATP 的弱非特异性相互作用对蛋白质的影响
DOI：
10.1021/jacs.0c13118
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发表时间：
2021-08-02
影响因子：
15
通讯作者：
Sugase, Kenji
中科院分区：
文献类型：
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作者：
Nishizawa, Mayu;Walinda, Erik;Sugase, Kenji
三磷酸腺苷（ATP）是一种研究非常充分的代谢产物，作为生命系统中的主要化学能量货币，核糖核酸的构建模块和激酶介导的信号传导中的磷酰基供体，具有多种关键的生化作用。有趣的是，ATP最近被提出作为一种水溶助长剂，抑制淀粉样蛋白的聚集;然而，与ATP共存对蛋白质产生的潜在机制和一般物理化学效应仍不清楚。通过结合NMR光谱和MD模拟，在这里，我们观察到ATP和各种蛋白质之间的弱但明确可测量和浓度依赖性的非共价相互作用。这种相互作用对于内在无序的蛋白质（α-突触核蛋白）和柔性区域中的残基（例如，环或末端）。如溶液NMR所示，ATP-蛋白质相互作用的结果是改变了蛋白质中溶剂暴露残基的水合作用。ATP与所有三种蛋白质相互作用的观察表明ATP是蛋白质的一般非特异性结合剂。几种互补的生物物理方法进一步证实，在类似于5-10 mM的生理浓度下，ATP开始通过镁螯合和螯合非依赖性机制形成寡聚体状态，与先前的研究一致。虽然观察到的ATP-蛋白质相互作用总体上相对较弱，但细胞中ATP（单体游离ATP、一价和二价离子结合ATP、寡聚和螯合ATP）与蛋白质的高比例表明，大多数蛋白质可能会与ATP（和化学相似的代谢物）发生短暂相互作用，从而赋予代谢物介导的蛋白质表面保护作用。
Adenosine triphosphate (ATP) is an immensely well-studied metabolite serving multiple key biochemical roles as the major chemical energy currency in living systems, a building block of ribonucleic acids, and a phosphoryl group donor in kinase-mediated signaling. Intriguingly, ATP has been recently proposed to act as a hydrotrope that inhibits aggregation of amyloidogenic proteins; however, the underlying mechanism and the general physicochemical effect that coexistence with ATP exerts on proteins remain unclear. By combining NMR spectroscopy and MD simulations, here we observed weak but unambiguously measurable and concentration-dependent noncovalent interactions between ATP and various proteins. The interactions were most pronounced for an intrinsically disordered protein (alpha-synuclein) and for residues in flexible regions (e.g., loops or termini) of two representative folded proteins (ubiquitin and the dimeric ubiquitinbinding domain of p62). As shown by solution NMR, a consequence of the ATP-protein interaction was altered hydration of solvent-exposed residues in the protein. The observation that ATP interacted with all three proteins suggests that ATP is a general nonspecific binder of proteins. Several complementary biophysical methods further confirmed that, at physiological concentrations of similar to 5-10 mM, ATP starts to form oligomeric states via magnesium-chelating and chelation-independent mechanisms, in agreement with previous studies. Although the observed ATP-protein interaction was relatively weak overall, the high ratio of ATP (monomeric free ATP, mono- and divalent ion-bound ATP, oligomeric and chelated ATP) to proteins in cells suggests that most proteins are likely to encounter transient interactions with ATP (and chemically similar metabolites) that confer metabolitemediated protein surface protection.