Du Pu, Li Ang, Li Xin, Zhang Yueheng, Do Changwoo, He Lilin, Rick Steven W, John Vijay T, Kumar Revati, Zhang Donghui
Department of Chemistry and Macromolecular Studies Group, Louisiana State University, Baton Rouge, Louisiana 70803, USA.
Phys Chem Chem Phys. 2017 Jun 7;19(22):14388-14400. doi: 10.1039/c7cp01602f.
Aggregation behavior of cyclic polypeptoids bearing zwitterionic end-groups in methanol has been studied using a combination of experimental and simulation techniques. The data from SANS and cryo-TEM indicate that the solution contains small clusters of these cyclic polypeptoids, ranging from a single polypeptoid chain to small oligomers, while the linear counterpart shows no cluster formation. Atomistic molecular dynamics simulations reveal that the driving force for this clustering behavior is due to the interplay between the effective repulsion due to the solvation of the dipoles formed by the charged end-groups in each polypeptoid chain and the attractive forces due to dipole-dipole interactions and the solvophobic effect.
采用实验和模拟技术相结合的方法，研究了带有两性离子端基的环状聚肽在甲醇中的聚集行为。小角中子散射（SANS）和冷冻透射电子显微镜（cryo-TEM）的数据表明，该溶液中含有这些环状聚肽的小聚集体，范围从单条聚肽链到小寡聚物，而线性聚肽则没有聚集体形成。原子分子动力学模拟表明，这种聚集行为的驱动力是由于每条聚肽链中带电端基形成的偶极子溶剂化所产生的有效排斥力与偶极-偶极相互作用和疏溶剂效应所产生的吸引力之间的相互作用。
