10.1021/jo951430o.s001
Ross V. Weatherman
Ross V.
Weatherman
Laura L. Kiessling
Laura L.
Kiessling
Fluorescence Anisotropy Assays Reveal Affinities of <i>C</i>- and
<i>O</i>-Glycosides for Concanavalin A<sup>1</sup>
American Chemical Society
1996
binding energies
concanavalin
0.5 kcal mol
Fluorescence Anisotropy Assays Reveal Affinities
ligand
glycosides
lectin carbohydrate binding site
1996-01-26 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Fluorescence_Anisotropy_Assays_Reveal_Affinities_of_i_C_i_-_and_i_O_i_-Glycosides_for_Concanavalin_A_sup_1_sup_/3700941
The free energies of binding of various <i>C</i>- and
<i>O</i>-glycosides to the lectin concanavalin A were
measured using fluorescence anisotropy. Fluorescein derivatives of
mannose and glucose were
synthesized and were shown to bind to concanavalin A with free energies
of −5.1 and −4.3 kcal
mol<sup>-1</sup>, respectively. Competition
experiments were performed to determine the binding
energies
of different nonfluorescent carbohydrates, and the results were in
excellent agreement with the
binding energies determined by microcalorimetry. The minimum
carbohydrate epitope that fills
the lectin carbohydrate binding site, methyl
3,6-di-<i>O</i>-(α-mannopyranosyl)-α-mannopyranoside,
competes directly for the site with the fluorescent ligands, indicating
that the fluorescent ligands
bind specifically. The binding affinities of
<i>C</i>-glycosides to concanavalin A were compared
with
those of <i>O-</i>glycosides. The free energies of binding for
corresponding <i>C</i>- and <i>O</i>-glycosides
differed
by less than 0.5 kcal mol<sup>-1</sup>, indicating that
recognition properties of <i>C</i>- and <i>O-</i>glycosides are
very
similar. It was found that for some ligands the use of a carbon
linkage rather than an oxygen
linkage caused the specificity of binding to decrease
slightly.