Classifying N-glycans
The Interns
Reference
GlycoMod
GlycoMod is a program designed to find all possible compositions
of a glycan structure from its experimentally determined mass.
This is done by comparing the mass of the glycan to a list of
pre-computed masses of glycan compositions.
http://web.expasy.org/glycomod/glycomod-doc.html
GlycoMod Rules
The glycan type of N-linked glycans is also given, i.e.,
hybrid/complex or high mannose (see figure below). These
are classified by:
– If the number of HexNAc residues equals 2 and the
number of hexose residues is greater than or equal to 5,
then the N-linked glycan is of the type “high mannose”.
– If the number of HexNAc residues is greater than or equal
to 3 and the number of hexose residues is also greater
than or equal to 3, then the N-linked glycan is of the type
“hybrid/complex”
High mannose
MAN/BMA
MAN/BMA
NAG
Hybrid
GAL
MAN/BMA
NAG
Complex
GAL
NAG
NAG
NDG
MAN/BMA MAN/BMA
FUC
NAG
GAL
1P8J
MANNOSE
NAG
FUCOSE
Linkages
3HN3
MAN
BMA
Classifications
High mannose
Hybrid
Complex
3OG2
3OGR
3HN3
2C4A
2C4L
2B8H
1YY9
1TG7
1XC6
1H4P
1CVI (CUT OFF)
3OGR
3HN3
3H32
3GWJ
2VUO
1T83
1T89
1H3V (FUCOSYLATED)
1I1A (FUCOSYLATED)
3OG2
2RGS
2VUO
2DW2
2J6E
1T83
1T89
1H3X
1P8J (CUT OFF)
1H3Y
1I1A
1E4K
1CVI
Our Rules
• If both branches have only BMA/MAN- high
mannose
• If one branch has only BMA/MAN and other
branch has other saccharides- hybrid
• If both branches have saccharides other than
BMA/MAN- complex
• If 1st NAG is fucosylated- cannot be high
mannose