Unveiling the structure of sulfated fucose-rich polysaccharides via nuclear magnetic resonance spectroscopy.

Sulfated fucans from marine invertebrates are composed of regular repetitive fucose building-blocks with sulfation patterns differing in a species-specific manner. These polysaccharides can act as mediators of the acrosome reaction of sea-urchins or play a structural role in the body-wall of sea-cucumbers. Other fucose-rich polysaccharides found in the body-wall of sea-cucumbers are the fucosylated chondroitin sulfates composed of a vertebrate-like chondroitin sulfate decorated with species-specific fucose branches.

Exploring the structure of fucosylated chondroitin sulfate through bottom-up nuclear magnetic resonance and electrospray ionization-high-resolution mass spectrometry approaches.

Fucosylated chondroitin sulfate (FCS) from sea cucumbers is composed of a chondroitin sulfate (CS) central core and branches of sulfated fucose. The structure of this complex glycosaminoglycan is usually investigated via nuclear magnetic resonance (NMR) analyses of the intact molecule, ergo through a top-down approach, which often yield spectra with intricate sets of signals. Here we employed a bottom-up approach to analyze the FCSs from the sea cucumbers Isostichopus badionotus and Ludwigothurea grisea from their basic constituents, viz.