K. Siridewa et al., CHARACTERIZATION OF GLYCOPROTEINS FROM CHLAMYDIA-TRACHOMATIS USING LECTINS, APMIS. Acta pathologica, microbiologica et immunologica Scandinavica, 101(11), 1993, pp. 851-857
Glycoproteins in Chlamydia trachomatis, serotype L1, elementary bodies
were studied by lectin blotting. A panel of 23 lectins representing a
variety of sugar specificities was used. The pattern of lectin-bindin
g specificities at a peptide band was studied in order to determine th
e type and structure of its glycoconjugate. To establish chlamydial or
igin of the glycopeptide bands in the blot, control samples from non-i
nfected host cell membranes were run in parallel. Terminal mannosidic
structures were demonstrated in a 72 kDa glycopeptide (gp72) by its se
lective binding of Galanthus nivalis lectin (GNA). Sialic acids were f
ound in two chlamydial glycopeptides, gp40 and gp64, which appear to c
arry O-linked glycoconjugates as they bound the peanut agglutinin (PNA
, both gp40 and gp64) and jackfruit lectin (Jac, only gp40). Such stru
ctures were also present in other chlamydial glycopeptides. Lectins wi
th specificities for fucose in different links, galactose and N-acetyl
glucosamine bound to several chlamydial peptides. On the basis of our
results we suggest an alternative mechanism for uptake of chlamydial
elementary bodies into host cells, namely phagocytosis mediated by euk
aryotic cell surface lectins.