Dayon L, Josserand J, Girault H H
Laboratoire d'Electrochimie Physique et Analytique, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
Phys Chem Chem Phys. 2005 Dec 21;7(24):4054-60. doi: 10.1039/b511334b. Epub 2005 Oct 25.
On-line electrogeneration of mass tags in a microspray emitter is used to quantify the number of cysteine groups in a given peptide. A finite-element simulation of the multi-step process yields the relative distribution and concentration of tags, untagged and tagged species in the microchannel before the spray event. The work focuses on the tagging of cysteine moieties in peptides or proteins by electrogenerated quinone mass probes. The main chemical parameters determining the kinetics of the labelling are assessed and discussed considering the microfluidic aspects of the process. The control of the tagging extent allows the simultaneous MS analysis of both the unmodified and modified peptide(s). The number of cysteine groups corresponds to the number of characteristic mass shifts observed from the unmodified peptide. The present theoretical work establishes the range of optimum conditions for the determination of the number of cysteine groups in peptides containing up to five cysteine groups.
在微喷雾发射器中在线电生成质量标签用于定量给定肽中半胱氨酸基团的数量。对多步过程的有限元模拟得出喷雾事件发生前微通道中标签、未标记和已标记物种的相对分布和浓度。这项工作聚焦于用电生成的醌质量探针标记肽或蛋白质中的半胱氨酸部分。考虑到该过程的微流体方面，评估并讨论了决定标记动力学的主要化学参数。标记程度的控制使得能够同时对未修饰和修饰的肽进行质谱分析。半胱氨酸基团的数量与从未修饰肽观察到的特征质量位移的数量相对应。目前的理论工作确定了测定含多达五个半胱氨酸基团的肽中半胱氨酸基团数量的最佳条件范围。
