[求助]NMR检测小分子配体与蛋白相互作用

rushui117

刚接触NMR，想用来检测一下一种三个苯环的小分子配体与一种三万KDa的蛋白的相互作用，

请教各位大侠，是做小分子的H谱呢？还是做大分子的H谱?

做的话对于溶剂有什么要求吗？蛋白用什么溶剂呢？小分子用DMSO溶解可以吗？

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各位大侠帮帮忙，不胜感激啊

syflu

应该是用std 实验吧。

rushui117

什么事STD实验啊？大侠能详细解释一下吗？小弟初次接触NMR

考洛希

同问。蛋白的核磁咋做？

syflu

 

STD NMR

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STD NMR ( O0 ~# ~ m7 \$ D, P experiments detect magnetization that is transferred from a receptor protein to a bound ligand. Only bound ligands show STD effects. The experiment may be ' {6 ?, k4 [, F. ?- v6 K# J0 e combined with virtually any other NMR experiment, and therefore is well suitable to tackle even very complex problems. In particular, in combination with multidimensional / p5 g( z k% k6 m/ g; p+ c: @+ ]; T NMR a full characterization of a bound ligand out of a mixture is straightforward. 2 k$ p$ N9 s1 D3 o/ ~0 j STD NMR is extremely robust and gives maximal effects at protein to ligand ratios $ v1 w. ~. \( O& X greater than ca. 1:100. It follows that less than 1 nmol of protein is necessary for screening. With the availability of so called cryo probes it will be possible to work with hundred pmol amounts of protein. The dissociation constant should be in the range between nM and mM. Therefore, STD NMR covers at least two orders of magnitudes more for dissociation constants than trNOE experiments. From competitive STD experiments dissociation constants may be derived.

" z+ M) Q7 {( Z% x4 F Schematic display of the STD NMR effect. Saturation of the protein leads to a direct saturation of those parts of ligand(s) in direct contact to the protein. By exchange between bound and free state the saturation is transported to solution and detected % U4 U9 x3 w6 f# B: z9 B+ r by subtracting a spectrum with saturation from a normal spectrum.
STD NMR gives precise information about the binding epitope of the ligand. This 5 ~$ P7 D3 o; _0 Z is very important information for the design of a potent drug. The optimal drug is of optimal size and optimal shape. The size is deduced from STD NMR, and the shape is delivered by trNOE experiments.