The structure of the extracellular cyclic (1->2)-ß-D-glucan secreted by Rhizobium tropici CIAT 899 has been studied by methylation analysis, ¹D and ²D NMR experiments, HPLC and FAB-MS. Molecular mechanics (MM2) and theoretical ³JHH coupling constants calculations were performed.

Molecular mechanics minimum energy conformation obtained for the cyclid glucan