Allison Stuart A, Wu Hengfu, Bui Tuyen M, Dang Lac, Huynh Giang H, Nguyen Tam, Soegiarto Linda, Truong Bi C
Department of Chemistry, Georgia State University, Atlanta, GA, USA.
J Sep Sci. 2014 Sep;37(17):2403-10. doi: 10.1002/jssc.201400484. Epub 2014 Jul 24.
In this work, we use coarse-grained modeling to study the free solution electrophoretic mobility of small highly charged peptides (lysine, arginine, and short oligos thereof (up to nonapeptides)) in NaCl and Na2SO4 aqueous solutions at neutral pH and room temperature. The experimental data are taken from the literature. A bead modeling methodology that treats the electrostatics at the level of the nonlinear Poisson Boltzmann equation developed previously in our laboratory is able to account for the mobility of all peptides in NaCl, but not Na2SO4. The peptide mobilities in Na2SO4 can be accounted for by including sulfate binding in the model and this is proposed as one possible explanation for the discrepancy. Oligo arginine peptides bind more sulfate than oligo lysines and sulfate binding increases with the oligo length.
在这项工作中，我们使用粗粒度模型来研究小的高电荷肽（赖氨酸、精氨酸及其短寡聚物（至多九肽））在中性pH和室温下于NaCl和Na2SO4水溶液中的自由溶液电泳迁移率。实验数据取自文献。我们实验室之前开发的一种在非线性泊松-玻尔兹曼方程层面处理静电作用的珠子建模方法，能够解释所有肽在NaCl中的迁移率，但无法解释在Na2SO4中的迁移率。通过在模型中纳入硫酸盐结合，可以解释肽在Na2SO4中的迁移率，这被认为是造成差异的一种可能解释。寡聚精氨酸肽比寡聚赖氨酸结合更多的硫酸盐，并且硫酸盐结合随着寡聚物长度的增加而增加。
