生物聚合物通过纳米孔时螺旋-卷曲两态转换的随机动力学研究

A stochastic dynamics study for helix-coil transition of individual polyadenylic acid molecules in a protein channel

通过建立两态模型,依据Kramers理论,研究了生物聚合物多聚腺苷酸poly(A)在通过纳米孔时螺旋-卷曲(Helix-Coil)两态转换.结果表明:Helix-Coil两态转换的特征时间与能量位垒呈现指数关系τ~eΔG/kBT.同时发现了poly(A)两态的特征时间随温度、电压、外力的变化关系.本研究有助于理解生物聚合物通过纳米孔时的动力学行为.

Helix-coil transition with individual polyadenylic acid molecule going through a protein channel was investigated by Kramers’ escape rate theory.The relation between characteristic lifetime of helix-coil transition and energy barrier was obtained asτ~eΔG/kBT.Characteristic lifetime of helix and the coil state depended on temperature,voltage and force applied on individual polyadenylic acid molecule.This will provide physical understanding of the stochastic dynamics of DNA going through a nano-channel.