1 research outputs found
Carbohydrate Composition of Carcinus aestuarii Hemocyanin
No full textThe hemocyanin of the crab Carcinus aestuarii contains
a carbohydrate moiety that represents 1.6% of
protein mass. This carbohydrate content is higher
than that exhibited by other arthropod hemocyanins
so far investigated. By combination of FPLC ion exchange
chromatography and reverse-phase HPLC, the
native oligomeric protein can be resolved into three
major and one minor electrophoretically pure fractions
that are found to be homogeneous by N-terminal
sequencing and correspond to the subunit polypeptide
chains. Sugar analysis on the different subunits reveals
that the subunit referred to as Ca2 is glycosylated,
with a carbohydrate content of 6.3%. By Ca2
trypsin digestion, separation of glycopeptides, and
amino acid sequencing, three consensus sequences for
O-glycosylation and one for N-glycosylation were
found. MALDI-MS was applied for the determination
of the molecular masses of the various glycopeptides
and peptides after removal of carbohydrates by neuraminidase and a-N-acetylgalactosaminidase
