蛋白N-糖基化分析方法研究进展

Advances on the Analysis Methods of N-glycosylation

糖基化是真核细胞最常见的蛋白转译后修饰方式之一,N-糖基化作为糖蛋白中最主要的糖基化类型,在许多生命活动中起重要作用,对糖蛋白N-糖链的定性及定量研究具有重要意义。常规N-糖基化分析策略多是将其从肽链上酶切游离后再分析,但N-糖链为多羟基醛类化合物,经典反相色谱与紫外检测方式对其分离分析较困难。针对这种情况,科学家多是通过柱前衍生法使糖链带上紫外或荧光基团,增加检测灵敏度。对近年来科学家分离分析游离N-糖链的方法做了归纳与总结,其中毛细管电泳、高效液相色谱以及质谱联用技术在N-糖链的分离分析上有着巨大优势,对糖蛋白上N-糖的定性定量、结构表征具有重要意义。与此同时应进一步发展稳定可靠的N-糖释放、富集方法,并结合现代高效的分析手段,以及有针对性的N-糖解析措施,以期为N-糖基化高通量、高准确性的分析提供依据。

Glycosylation is one of the most common forms of post-translational modifications in eukaryotic proteins. As the main glycosylation type of glycoproteins, N-glycosylation plays an important role in many life activities. It has positive practical significance for qualitative and quantitative research of N-glycans. The conventional analysis strategy of N-glycosylation is to separate the N-glycans from the peptide chain by enzymatic digestion. But it is difficult to separate and analyze the N-glycans by classical reversed-phase chromatography and ultraviolet detection, because of the N-glycans is a polyhydroxyaldehyde compound. In response to this situation, scientists mostly use pre-column derivatization to make the sugar chains with ultraviolet or fluorescent groups, so as to increase the sensitivity of their detection. In this paper, the methods of separation and analysis for dissociative N-glycans were summarized in recent years. Among them, CE, HPLC and MS have great advantages in the separation and analysis of N-glycans, which are of great significance for the qualitative, quantitative and structural characterization of N-glycans in glycoproteins. Meanwhile, stable and reliable methods for N-glycans release and enrichment should be further developed, combined with modern efficient analytical methods and targeted measures for N-glycans analysis, which was expected to provide a basis for the analysis of N-glycosylation with high flux and accuracy.