Studies of low molecular weight samples generated by ultrasonic treatment of glucuronans with various acetylation degree

Corinne Pau-Roblot (1) , Emmanuel Petit (2) , Catherine Sarazin (1) , Josiane Courtois (3) , Bernard Courtois (3) , Jean Noël Barbotin (1) , Jean Paul Séguin (1)

1 GEC - Génie Enzymatique et Cellulaire
2 BIOPI - Biologie des Plantes et Innovation - UR UPJV 3900
3 LG - Laboratoire des Glucides

Partially acetylated, high molecular weight glucuronans were produced by a Sinorhizobium meliloti mutant strain. Two native glucuronan samples with various degrees of acetylation were sonicated to obtain lower molecular weight samples and with low viscosity suitable for chemical modification and 13C NMR experiments. The average degree of substitution of the polymer was estimated by Fourier transform infrared (FTIR) and NMR. 13C NMR spectra were obtained and used to suggest a complete assignment of the signals. The nuclear Overhauser effect spectroscopy (NOESY) and heteronuclear multi-bond coherence (HMBC) experiments were used to elucidate connectivities between the various residues and deduce the linkage of these residues within the polysaccharide.

Mots clés: exopolysaccharide; acetylation; two-dimensional NMR; 13C NMR; Fourier transform infrared

Domaines: Génie chimique

Corinne Pau-Roblot, Emmanuel Petit, Catherine Sarazin, Josiane Courtois, Bernard Courtois, et al.. Studies of low molecular weight samples generated by ultrasonic treatment of glucuronans with various acetylation degree. Biopolymers, 2002, 64 (1), pp.34-43. ⟨10.1002/bip.10134⟩. ⟨hal-00087968⟩