摘要
运用密度泛函(DFT)B3LYP方法和半经验分子轨道方法AM1对四种环状多肽[-(L-Asn-Ala)4-],[-(L-Asp-Ala)4-],[-(L-Gln-Ala)4-]和[-(L-Glu-Ala)4-]的单体、平行和反平行二聚体到十聚体进行了理论研究.结果表明,四种环状多肽无论以平行还是以反平行的方式聚集,聚集体中相邻两个环状多肽的侧链之间都能形成氢键.侧链间氢键的相互作用使得这些环状多肽在组装过程中的结构和能量变化均表现出一定的协同效应,这种协同效应加强了多肽纳米管的稳定性,同时对聚集模式的选取起到了决定性作用.
A series of parallel and antiparallel oligomers of cyclo [-（L-Asn-Ala）4^-],cyclo[-（L-Asp-Ala）4^-],[-（L-GIn-Ala）4^-]and[-（L-Glu-Ala）4^-] were investigated by using density functional methods B3LYP and semiempirical molecular orbital method AM1. The results of this study indicate that when these cyclic peptides self-assemble as either parallel or antiparallel stacking modes, hydrogen bonds could be formed between side chains of Asn, Asp, Gln and Glu. Significantly, the interactions between side-chain hydrogen bonds result in the cooperative effect of the assembly energetics, which facilitates the cyclic peptides to form stable nanotubes and have the most dominant effect on determining the preference for parallel vs. antiparallel stacking.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2007年第2期307-311,共5页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:20231010
20271009
20503002)
国家重点基础研究发展计划(批准号:G2004CB719900)资助
