Details:
An N-linked glycosylation site pattern, NX[ST] (where X can be any amino acid),
is called a sequon. This pattern forms the basis for most of the analyses on this
web site. The extent of N-linked glycosylation of a particular N-linked
glycosylation site, however, can be influenced by the content in which it is
embedded, and could be expanded to a 4-amino acid NX[ST]Y pattern, where the
amino acid in the X or Y position of NX[ST]Y pattern can be important determinants
of N-linked glycosylation efficiency. For example, a proline in position X or Y
strongly disfavors N-linked glycosylation. Thus we provide NX[ST] or NX[ST]Y
summaries.
O-linked glycosylation signals are more difficult predict in protein sequences than N-linked sites, but one can estimate their positions in sequences using the NetPhos program (at Center for Biological Sequence Analysis).
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