In vitro and in vivo enzymatic syntheses and mass spectrometric database for N-glycans and o-glycans.

In the GlycoGene Project, we have comprehensively cloned novel human genes associated with the synthesis of glycans using bioinformatics technology. Recombinant glycosyltransferases can be expressed in various expression systems. Diverse glycan structures are easily and rapidly achieved using these glycosyltransferases in vitro. Additionally, we have developed an in vivo production system for mammalian mucin-type glycopeptides using a genetically engineered yeast strain. This system enables the generation of glycopeptides which are O-glycosylated on a specific position by introducing different types of ppGalNAc-T genes. As an application of the glycan and glycopeptide libraries to glycan analysis, we have constructed a multistage tandem mass (MS(n)) spectral database containing observed MS(n) spectra. Using the MS(n) spectral database, it is possible to identify glycan structures very easily and rapidly by spectral matching.