Liu Wenjie, Guo Xia, Guo Rong
School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu 225002, PR China.
Int J Biol Macromol. 2007 Dec 1;41(5):548-57. doi: 10.1016/j.ijbiomac.2007.07.006. Epub 2007 Jul 20.
The interactions of hemoglobin (Hb) with sodium dodecyl sulfate (SDS) and dodecyl trimethylammonium bromide (DTAB) are investigated by several methods. We observed the formation of hemichrome below the critical micelle concentration (cmc) of surfactant and the release of heme from Hb above the cmc. When pH value of Hb/surfactant system is lower than isoelectric point (pI) of Hb, the interaction of SDS with Hb is both electrostatic and hydrophobic, while the interaction of DTAB with Hb is hydrophobic mainly. On the contrary, when pH>pI, the interaction of SDS with Hb is hydrophobic mainly, while the interaction of DTAB with Hb is both electrostatic and hydrophobic. In the case where both the electrostatic interaction and hydrophobic interaction exist, the electrostatic interaction plays a more important role. Thus, SDS tends to interact with Hb more obviously than DTAB does when pH
通过多种方法研究了血红蛋白（Hb）与十二烷基硫酸钠（SDS）和十二烷基三甲基溴化铵（DTAB）之间的相互作用。我们观察到在表面活性剂的临界胶束浓度（cmc）以下形成了高铁血红素，在cmc以上则有血红素从Hb中释放出来。当Hb/表面活性剂体系的pH值低于Hb的等电点（pI）时，SDS与Hb的相互作用既有静电作用又有疏水作用，而DTAB与Hb的相互作用主要是疏水作用。相反，当pH>pI时，SDS与Hb的相互作用主要是疏水作用，而DTAB与Hb的相互作用既有静电作用又有疏水作用。在同时存在静电相互作用和疏水相互作用的情况下，静电相互作用起更重要的作用。因此，当pH<pI时，SDS比DTAB更倾向于与Hb明显相互作用，而当pH>pI时，DTAB与Hb之间的相互作用更强。
