Positive cooperative mechanistic binding of proteins at low concentrations: a comparison of poly (sodium N-undecanoyl sulfate) and sodium dodecyl sulfate.
Positive cooperative mechanistic binding of proteins at low concentrations: a comparison of poly (sodium N-undecanoyl sulfate) and sodium dodecyl sulfate.
复制标题
低浓度下蛋白质的正协同机械结合：聚（N-十一酰硫酸钠）和十二烷基硫酸钠的比较。
DOI：
10.1016/j.jcis.2011.07.044
复制
发表时间：
2011
影响因子：
9.9
通讯作者：
Warner,IsiahM
中科院分区：
文献类型：
--
作者：
Das,Susmita;Sylvain,MonicaR;Fernand,VivianE;Losso,JackN;El-Zahab,Bilal;Warner,IsiahM
研究了带负电荷的非手性分子胶束聚十一烷酰硫酸钠（poly-SUS）与四种不同蛋白质的相互作用。还报道了聚SUS与常规表面活性剂十二烷基硫酸钠（SDS）和单体物种SUS的比较。在这项工作中，我们观察到poly-SUS优先结合酸性蛋白质，对所有研究的蛋白质在低于1 mM的浓度下表现出正协同性。此外，似乎通过单体SUS的末端乙烯基的聚合形成的疏水微区是聚SUS的上级结合能力的主要原因。从这些结果中，我们得出结论，聚SUS与酸性蛋白质的相互作用主要是疏水性的，并假设聚SUS在聚丙烯酰胺凝胶电泳（PAGE）中在低浓度下相对于SDS产生上级相互作用。如所预测的，使用poly-SUS允许在低至0.08%w/v（2.9mM）的样品缓冲液浓度下分离His标记的肿瘤抑制蛋白p53，这比标准还原PAGE方案中SDS所需的低24倍。这项工作突出了使用聚SUS作为一种有效的表面活性剂在一维生化分析。
The interactions of the negatively charged achiral molecular micelle, poly (sodium N-undecanoyl sulfate) (poly-SUS), with four different proteins using intrinsic and extrinsic fluorescence spectroscopic probes, are studied. A comparison of poly-SUS with the conventional surfactant, sodium dodecyl sulfate (SDS), and the monomeric species, SUS, is also reported. In this work, we observed that poly-SUS preferentially binds to acidic proteins, exhibiting positive cooperativity at concentrations less than 1mM for all proteins studied. Moreover, it appears that the hydrophobic microdomain formed through polymerization of the terminal vinyl group of the monomer, SUS, is largely responsible for the superior binding capacity of poly-SUS. From these results, we conclude that the interactions of poly-SUS with the acidic proteins are predominantly hydrophobic and postulate that poly-SUS would produce superior interactions relative to SDS at low concentrations in polyacrylamide gel electrophoresis (PAGE). As predicted, use of poly-SUS allowed separation of the His-tagged tumor suppressor protein, p53, at sample buffer concentrations as low as 0.08% w/v (2.9mM), which is 24 times lower than required for SDS in the standard reducing PAGE protocol. This work highlights the use of poly-SUS as an effective surfactant in 1D biochemical analysis.