Lee H G, Desiderio D M
Charles B. Stout Neuroscience Mass Spectrometry Laboratory, University of Tennessee at Memphis 38163.
J Chromatogr A. 1994 Apr 29;667(1-2):271-83. doi: 10.1016/0021-9673(94)89076-5.
Capillary zone electrophoresis was performed on fourteen synthetic opioid peptides and one tachykinin peptide (substance P = SP) at pH values of 2.5, 5.5 and 8.5 to rationalize the electrophoretic behavior of these neuropeptides. A plot of the theoretical q/M(r)2/3 values (where q = peptide charge) calculated across the pH range of 1 to 10 for these peptides was used to understand and to predict their separation. The experimentally determined electrophoretic mobilities (mu) were correlated to the estimate of the relative mu predicted by q/M(r)2/3 and by [ln (q + 1)]/n0.43 (where n = number of constituent amino acids), where q values were calculated using amino acid pKa values for an isolated amino acid and for an amino acid in a peptide. In general, relatively high correlations were obtained with either mathematical expression and with both sets of amino acid pKa values for data at a single pH value. However, the combination of the former expression and the adjusted pKa values gave the best prediction of electrophoretic behavior when data for the three pH values were correlated across these different separation conditions.
在pH值为2.5、5.5和8.5的条件下，对14种合成阿片肽和1种速激肽（P物质=SP）进行了毛细管区带电泳，以阐明这些神经肽的电泳行为。利用在1至10的pH范围内计算得到的这些肽的理论q/M(r)2/3值（其中q =肽电荷）绘制的图，来理解和预测它们的分离情况。将实验测定的电泳迁移率（μ）与通过q/M(r)2/3和[ln (q + 1)]/n0.43（其中n =组成氨基酸的数量）预测的相对μ估计值相关联，其中q值是使用孤立氨基酸和肽中氨基酸的氨基酸pKa值计算得出的。一般来说，对于单一pH值的数据，用任一种数学表达式以及两组氨基酸pKa值都能得到相对较高的相关性。然而，当将这三个pH值的数据在这些不同的分离条件下进行关联时，前一种表达式与调整后的pKa值的组合对电泳行为给出了最佳预测。
