On the Conformational Properties of Amylose andCellulose Oligomers in Solution

[摘要] Molecular dynamics (MD) simulations were used to monitor the stability andconformation of double-stranded and single-stranded amyloses and single-strandedcellulose oligomers containing 9 sugar moieties in solution as a function of solventcomposition, ionic strength, temperature, and methylation state. This study alongwith other previous studies suggests that hydrogen bonds are crucial for guaranteeingthe stability of the amylose double helix. Single-stranded amylose forms a helicalstructure as well, and cellulose stays highly elongated throughout the simulation time, abehavior that was also observed experimentally. In terms of coordination of solutehydroxyl groups with ions, amylose shows entropy-driven coordination of calciumand sulfate ions, whereas cellulose-ion coordination seems to be enthalpy-dominated.This indicates that entropy considerations cannot be neglected when explaining thestructural differences between amyloses and celluloses.

[学科分类] 有机化学