Probing non-specific interactions of Ca2+-calmodulin in E. coli lysate
Probing non-specific interactions of Ca2+-calmodulin in E. coli lysate
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DOI：
10.1007/s10858-013-9705-2
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发表时间：
2013-03-01
影响因子：
2.7
通讯作者：
Kay, Lewis E.
中科院分区：
文献类型：
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作者：
Latham, Michael P.;Kay, Lewis E.
蛋白质执行其功能的生物环境是一个拥挤的环境，其中包含数百万个分子，这些分子可能会导致大量瞬时的、非特定的相互作用。核磁共振光谱学特别适合于研究这些弱分子接触。在这里，用Ile、Leu、Val和Met甲基探针研究了钙离子结合形式的钙调蛋白(CaM)与大肠杆菌裂解物中非同源蛋白之间的非特异性相互作用。测量CaM甲基化学位移随添加的大肠杆菌裂解物的变化，以确定钙-CaM与大肠杆菌裂解物蛋白质相互作用的最小“平均”离解常数。H-2R(2)和C-13R(1)的自旋弛豫速率也报道了结合反应。我们的结果进一步强调了含甲基侧链在表征生物分子相互作用方面的能力，即使在复杂的细胞内环境中也是如此。
The biological environment in which a protein performs its function is a crowded milieu containing millions of molecules that can potentially lead to a great many transient, non-specific interactions. NMR spectroscopy is especially well suited to study these weak molecular contacts. Here, non-specific interactions between the Ca2+-bound form of calmodulin (CaM) and non-cognate proteins in Escherichia coli lysate are explored using Ile, Leu, Val and Met methyl probes. Changes in CaM methyl chemical shifts as a function of added E. coli lysate are measured to determine a minimum 'average' dissociation constant for interactions between Ca2+-CaM and E. coli lysate proteins. H-2 R (2) and C-13 R (1) spin relaxation rates report on the binding reaction as well. Our results further highlight the power of methyl containing side-chains for characterizing biomolecular interactions, even in complex in-cell like environments.