Molecular Modeling of Carbohydrates with No Charges, No Hydrogen Bonds, and No Atoms

We review the M3B coarse grain model for glucans and their aqueous mixtures that we show is able to describe the helical structures of oligo- and polysaccharides, experimental glass transition temperatures, and the dynamics of water in supercooled and glassy malto-oligosaccharide mixtures. M3B involves no electrostatic interactions, no hydrogen bonds, and no other directional nonbond interaction. Indeed M3B has no atoms, just three connected beads per monomer. M3B permits coarse grain simulations ~7000 faster times than atomistics, yet provides at the end a mapping back to the full atomistic description.