AUTHOR=Li Shanshan , Wang Jiajia , Zang Lanlan , Zhu Hailiang , Guo Jianshuang , Zhang Jiabin , Wen Liuqing , Chen Yi , Li Yanhong , Chen Xi , Wang Peng George , Li Jing TITLE=Production of Glycopeptide Derivatives for Exploring Substrate Specificity of Human OGA Toward Sugar Moiety JOURNAL=Frontiers in Chemistry VOLUME=Volume 6 - 2018 YEAR=2019 URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2018.00646 DOI=10.3389/fchem.2018.00646 ISSN=2296-2646 ABSTRACT=O-GlcNAcase (OGA) is the only enzyme responsible for removing N-acetyl glucosamine (GlcNAc) attached to serine and threonine residues on proteins. This enzyme plays a key role in O-GlcNAc metabolism. However, the structural features of the sugar moiety recognized by human OGA (hOGA) remain unclear. In this study, a set of glycopeptides with modifications on the GlcNAc residue were prepared in a recombinant full-length human OGT-catalyzed reaction using chemoenzymatically synthesized UDP-GlcNAc derivatives. The resulting glycopeptides were used to evaluate the substrate specificity of hOGA towards the sugar moiety, we anticipate this study will provide insight into the exploration of probes for O-GlcNAc modification as well as better understanding the roles of O-GlcNAc in cellular physiology.