Mass spectrometric analysis of glycans in elucidating the pathogenesis of CDG type IIx .

The majority of secreted or membrane-bound proteins are glycosylated. The glycans attached to glycoproteins can affect a range of physicochemical and biological properties of the glycoprotein and appropriate glycosylation is essential for many normal cellular functions, with aberrant glycosylation often leading to disease. This short review briefly outlines the methodology used to release glycans from proteins and analyse them by mass spectrometry. The technology is illustrated by the description of a rapid and sensitive method for profiling glycoproteins of patients with congenital disorders of glycosylation type II. This methodology can rapidly pinpoint the defective step(s) in the processing pathway of N-linked glycans, thereby focusing the biochemical analyses that need to be performed to define the genetic basis of these diseases.