We report O-Pair Search, an approach to identify O-glycopeptides and localize O-glycosites. Using paired collision- and electron-based dissociation spectra, O-Pair Search identifies O-glycopeptides via an ion-indexed open modification search and localizes O-glycosites using graph theory and probability-based localization. O-Pair Search reduces search times more than 2,000-fold compared to current O-glycopeptide processing software, while defining O-glycosite localization confidence levels and generating more O-glycopeptide identifications. Beyond the mucin-type O-glycopeptides discussed here, O-Pair Search also accepts user-defined glycan databases, making it compatible with many types of O-glycosylation. O-Pair Search is freely available within the open-source MetaMorpheus platform at https://github.com/smith-chem-wisc/MetaMorpheus.

我们报告了O-Pair Search，这是一种识别O-糖肽和本地化O-糖苷的方法。使用成对的基于碰撞和电子的解离光谱，O-Pair Search通过离子索引的开放修饰搜索识别O-糖肽，并使用图论和基于概率的定位对O-糖苷进行定位。与当前的O-糖肽处理软件相比，O-Pair Search的搜索时间减少了2,000倍以上，同时定义了O-糖位定位的置信度并产生了更多的O-糖肽鉴定。除了此处讨论的粘蛋白型O-糖肽外，O-Pair Search还接受用户定义的聚糖数据库，从而使其与许多类型的O-糖基化兼容。O-Pair搜索可在开源MetaMorpheus平台上免费获得，网址为https://github.com/smith-chem-wisc/MetaMorpheus。