NMR spectroscopy reveals cytochrome c-poly(ethylene glycol) interactions
NMR spectroscopy reveals cytochrome c-poly(ethylene glycol) interactions
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DOI：
10.1002/cbic.200700603
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发表时间：
2008-03-25
期刊：
影响因子：
3.2
通讯作者：
Muldoon, Jimmy
中科院分区：
文献类型：
--
作者：
Crowley, Peter B.;Brett, Keith;Muldoon, Jimmy
体外蛋白质研究通常在几乎完全由水组成的样品上进行。然而，细胞内部是小分子、蛋白质、核酸和膜的异质“拥挤”溶液。在浓度为300-400 g LIGHT 1时，细胞的大分子含量通过排除体积效应影响蛋白质折叠、配体结合和蛋白质-蛋白质相互作用的动力学和热力学。[1-3]因此，为了建立蛋白质结构和功能的真实模型，有必要在体内或在模拟细胞环境的“拥挤”条件下研究蛋白质。细胞内NMR光谱的发展正在解决体内蛋白质表征的必要性。[4-6]虽然“生物惰性”蛋白质在很大程度上不受拥挤的细胞内部的影响，[6]无序蛋白FlgM被证明在大肠杆菌细胞内获得结构。[5]在拥挤剂的存在下，在体外发生了类似的结构增益。[5]通过使用糖、蛋白质或聚合物如Ficoll、葡聚糖和聚乙二醇（PEG），可以创造出拥挤的环境。[1-3]这样的样品条件是可访问的NMR光谱，和大分子拥挤蛋白质结构和动力学的影响进行了研究。[4-11]通过使用聚丙烯酰胺凝胶、[12]反胶束、[13]溶胶-凝胶[14]和琼脂糖凝胶进行了大分子限制的相关NMR研究。[15]通常，拥挤/限制倾向于加速蛋白质折叠，促进自缔合并稳定蛋白质结构。
In vitro protein studies are typically performed on samples that are composed almost entirely of water. However, the cell interior is a heterogeneous “crowded” solution of small molecules, proteins, nucleic acids and membranes. At a concentration of 300–400 g LÀ1, the macromolecular content of the cell influences the kinetics and thermodynamics of protein folding, ligand binding and protein–protein interactions through excluded volume effects.[1–3] Therefore, in order to build realistic models of protein structure and function, it is necessary to study proteins in vivo or under “crowded” conditions that mimic the cellular environment.The necessity for in vivo protein characterisation is being addressed by the development of in-cell NMR spectroscopy.[4–6] While “biologically inert” proteins are largely unaffected by the crowded cell interior,[6] the disordered protein FlgM was shown to gain structure inside Escherichia coli cells.[5] A similar gain in structure occurred in vitro in the presence of crowding agents.[5] Artificially crowded environments can be created by using sugars, proteins or polymers such as Ficoll, dextran and poly (ethylene glycol)(PEG).[1–3] Such sample conditions are accessible by NMR spectroscopy, and the effects of macromolecular crowding on protein structure and dynamics have been investigated.[4–11] Related NMR studies of macromolecular confinement have been performed by using polyacrylamide gels,[12] reverse micelles,[13] sol–gels [14] and agarose gels.[15] Generally, crowding/confinement tends to accelerate protein folding, promotes self-association and stabilises protein struc-