Chemical Approaches to Elucidate Enzymatic Profiles of UDP-Glucose: Glycoprotein Glucosyltransferase.

In the endoplasmic reticulum (ER), uridine 5'-diphosphate-glucose: glycoprotein glucosyltransferase 1 (UGGT1) recognizes misfolded glycoproteins and transfers a glucose residue to the specific non-reducing end of high-mannose-type glycans. However, precise molecular mechanism by which UGGT1 senses the folding has not been understood clearly. To address this issue, various model substrates for UGGT1 have been prepared using biological approaches. Recently, we introduced chemical approaches using synthetic glycan probes that were designed for studying N-glycan processing in the ER and Golgi apparatus. Our approach can outfit the homogeneous and functionalized glycan probes. In this review, recent results on functional analysis of UGGT1 are summarized.