Figure 1.

Comparison of the glycan features in electron density maps over a range of resolutions from selected glycoprotein structures (PDB entries: 6RI6 [19]; 6MZK [20]; 4O5I [21]). The electron density maps were obtained with X-ray crystallography. The data resolution and PDB entry IDs associated with the structures have been directly annotated on the structure. Left: A high-resolution example where monosaccharides and the conformations can be elucidated; middle: A medium resolution example where the identification starts to become difficult; right: A low-resolution example for which all prior knowledge must be used. Despite coming from different glycoprotein structures, the glycan has the same composition, and thus is assigned a unique GlyTouCan ID of G15407YE.