**2. The commonalities between mosses and vascular plants**

A number of investigations have shown that *P. patens* behave just like a tracheal plant when it comes to protein N-glycosylation. Biosynthesis and structures of plant N-glycans have been reviewed in many previous papers [4–6] and hence we only give–for the sake of comprehensiveness–a short overview. The biosynthetic routes from the ubiquitous oligomannosidic (*aka* high-mannose) structures lead to the check-point Man5Gn after which it branches out in various ways by combining a, however, limited, set of biosynthetic steps.


*Protein Glycosylation in Bryophytes Differs Subtly from That in Vascular Plants DOI: http://dx.doi.org/10.5772/intechopen.107035*


A few main roads are depicted in **Figure 1**, which also gives names to the structures. To understand this naming system, we humbly ask the reader to remember that the "proglycan" nomenclature starts in the upper left corner and then lists the terminal residues in the counter-clockwise direction, whereby M, A, Gn, X, and F stand for mannose, galactose, *N*-acetylglucosamine, xylose, and fucose, respectively [9]. The branched Lewis A determinant of large plant N-glycans can either be written as "(FA)" or—more reader-friendly—as "La."
