Theoretical and Experimental Conformational Studies of Oligoglucosides Structurally Related to Fragments of Fungal Cell Wall β-(1→3)-D-Glucan

Abstract

The conformational behavior of linear oligo-β-(1→3)-D-glucosides was studied using NMR experiments and molecular modeling. The explicit solvent model in calculations yielded the best coincidence between experimental and theoretical values of NOE and spin-spin coupling constants to evidence the strong influence of solvation upon the conformations of the oligoglucosides. Long-range coupling constants calculated for di- and trimeric clusters of the studied glucosides fit the experimental data much better than the single-molecule approach. It was shown that conformational properties of disaccharide fragments in studied oligoglucosides depended on neither their position in the chain nor the length of the chain.

Keywords:

• β-Glucan
• Molecular modeling
• Solvent-accessible surface area
• explicit solvent model
• Transglycosidic coupling constants
• Molecular association

ACKNOWLEDGMENTS

This work was supported by the grant of the Russian Foundation for Basic Research 10-03-01012-a (A.G. Gerbst) and by the grant of the President of the Russian Federation to Young Scientists MK-5544.2010.3 (A.A. Grachev).