In biochemistry, paucimannosylation is an enzymatic post-translational modification involving the attachment of relatively simple mannose (Man) and N-Acetylglucosamine (GlcNAc) containing carbohydrates (glycans) to proteins. The paucimannosidic glycans may also be modified with other types of monosaccharides including fucose (Fuc) and xylose (Xyl) depending on the species, tissue and cell origin.
Paucimannosylation forms a separate sub-type in the asparagine N-linked glycosylation system. The short paucimannosidic glycans neither structurally nor functionally fit into the three well-established N-glycan classes i.e. oligomannosidic-, hybrid- and complex-type N-glycans.
Paucimannosylation has traditionally been referred to as a N-glycosylation type of "lower organisms", mostly documented in insects, worms and plants. Recent findings have, however, added nuances to this view, by showing their presence and roles in mammals in the areas of immunity, cellular development, pathogen infection and cancer. To this end, paucimannosylation is therefore now considered to be a distinct type of N-glycosylation that adds diversity to the highly heterogeneous glycoproteome across the eukaryotic domain.