基于碘乙酸功能化树枝状聚合物的硫巯化肽段选择性富集新方法

蛋白质的硫巯化是一种重要的氧化翻译后修饰,在细胞衰老、内质网应激、血管舒张、细胞凋亡等过程中扮演重要角色。利用蛋白质组学技术表征硫巯化修饰具有十分重要的意义。该文发展了一种基于碘乙酸功能化的聚酰胺-胺树枝状聚合物(PAMAM-INS),并结合滤膜辅助的样品预处理技术用于硫巯化肽段的富集(简称FADE策略),利用FADE策略能从100倍质量干扰的牛血清白蛋白酶解产物中选择性地富集出硫巯化标准肽段。将细胞培养稳定同位素标记技术引入到FADE策略中,并将其应用于不同浓度梯度硫氢化钠刺激的SHSY5Y细胞硫巯化蛋白质组分析,共鉴定到163条硫巯化肽段。生物信息学的结果表明,硫巯化修饰可能在中枢神经系统中扮演着重要角色。

A novel method for the selective enrichment of persulfidated peptides based on iodoacetic acid functionalized dendrimer

Protein persulfidation is an important oxidative translational modification which plays vital roles in many important processes including cellular senescence, endoplasmic reticulum stress, vasorelaxation, and apoptosis. The proteome-wide analysis of persulfidation is of great importance; therefore, this study combines filter-aided sample preparation with an iodoacetic acid functionalized polyamidoamine dendrimer to enrich persulfidated peptides (denoted as filter-aided dendrimer enrichment strategy, FADE). To evaluate the performance of this strategy, the synthetic persulfidated standard peptide was spiked into bovine serum albumin (BSA) digests at a mass ratio of 1:100, and was successfully identified by FADE. Moreover, in combination with stable isotope labelling by amino acids in cell culture technology, the FADE strategy was applied to enrich persulfidated peptides from NaHS-stimulated SHSY5Y cells over a concentration gradient, resulting in the identification of 163 persulfidated peptides. Bioinformatic analysis indicated that persulfidation might play important roles in the central nervous system.