Zhang Ran, Linse Per
Physical Chemistry, Department of Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
J Chem Phys. 2014 Jun 28;140(24):244903. doi: 10.1063/1.4883056.
On the basis of a T = 1 icosahedral capsid model, the capsomer-polyion co-assembly process has been investigated by molecular dynamics simulations using capsomers with different net charge and charge distribution as well as linear, branched, and hyper-branched polyions. The assembly process was characterized in terms of the time-dependent cluster size probabilities, averaged cluster size, encapsulation efficiency, and polyion extension. The kinetics of the capsid formation displayed a two-step process. The first one comprised adsorption of capsomers on the polyion, driven by their electrostatic attraction, whereas the second one involved a relocation and/or reorientation of adsorbed capsomers, which rate is reduced upon increasing electrostatic interaction. We found that increased polyion branching facilitated a more rapid encapsulation process towards a higher yield. Moreover, the hyper-branched polyions were entirely encapsulated at all polyion-capsid charge ratios considered.
基于T = 1二十面体衣壳模型，通过分子动力学模拟研究了衣壳粒-聚离子共组装过程，使用了具有不同净电荷和电荷分布的衣壳粒以及线性、支化和超支化聚离子。根据随时间变化的簇大小概率、平均簇大小、包封效率和聚离子伸展来表征组装过程。衣壳形成的动力学表现为两步过程。第一步包括衣壳粒在聚离子上的吸附，这是由它们的静电引力驱动的，而第二步涉及吸附的衣壳粒的重新定位和/或重新定向，随着静电相互作用的增加，其速率降低。我们发现，增加聚离子的支化有利于更快地进行封装过程，从而获得更高的产率。此外，在所有考虑的聚离子-衣壳电荷比下，超支化聚离子都被完全封装。
