The most abundant proteins in vertebrates – the collagen family proteins – play structural and biological roles in the body. The predominant member, type I collagen, provides tissues and organs with structure and connectivity. This protein has several unique post-translational modifications that take place intra- and extra-cellularly. With growing evidence of the relevance of such post-translational modifications in health and disease, the biological significance of O-linked collagen glycosylation has recently drawn increased attention. However, several aspects of this unique modification – the requirement for prior lysyl hydroxylation as a substrate, involvement of at least two distinct glycosyl transferases, its involvement in intermolecular crosslinking – have made its molecular mapping and quantitative characterization challenging. Such characterization is obviously crucial for understanding its biological significance. Recent progress in mass spectrometry has provided an unprecedented opportunity for this type of analysis. This review summarizes recent advances in the area of O-glycosylation of fibrillar collagens and their characterization using state-of-the-art liquid chromatography–mass spectrometry-based methodologies, and perspectives on future research. The analytical characterization of collagen crosslinking and advanced glycation end-products are not addressed here.

脊椎动物中最丰富的蛋白质——胶原蛋白家族蛋白质——在体内发挥结构和生物学作用。主要成员 I 型胶原蛋白为组织和器官提供结构和连接性。该蛋白质具有多种发生在细胞内和细胞外的独特翻译后修饰。随着越来越多的证据表明这种翻译后修饰与健康和疾病的相关性，O-连接胶原蛋白糖基化的生物学意义最近引起了越来越多的关注。然而，这种独特修饰的几个方面——需要事先赖氨酰羟基化作为底物、涉及至少两种不同的糖基转移酶、其参与分子间交联——使其分子作图和定量表征具有挑战性。这种表征显然对于理解其生物学意义至关重要。质谱分析的最新进展为此类分析提供了前所未有的机会。本综述总结了纤维状胶原蛋白O-糖基化领域的最新进展及其使用最先进的液相色谱-质谱法进行表征，以及对未来研究的展望。这里不讨论胶原交联和高级糖基化终产物的分析表征。