Hamley Ian W, Adak Anindyasundar, Castelletto Valeria
School of Chemistry, Food Biosciences and Pharmacy, University of Reading, Whiteknights, Reading, RG6 6AD, UK.
Nat Commun. 2024 Aug 8;15(1):6785. doi: 10.1038/s41467-024-51234-8.
Lipopeptides can self-assemble into diverse nanostructures which can be programmed to incorporate peptide sequences to achieve a remarkable range of bioactivities. Here, the influence of peptide sequence and chirality on micelle structure and interactions is investigated in a series of lipopeptides bearing two lysine or D-lysine residues and tyrosine or tryptophan residues, attached to a hexadecyl lipid chain. All molecules self-assemble into micelles above a critical micelle concentration (CMC). Small-angle x-ray scattering (SAXS) is used to probe micelle shape and structure from the form factor and to probe inter-micellar interactions via analysis of structure factor. The CMC is obtained consistently from surface tension and electrical conductivity measurements. We introduce a method to obtain the zeta potential from the SAXS structure factor which is in good agreement with directly measured values. Atomistic molecular dynamics simulations provide insights into molecular packing and conformation within the lipopeptide micelles which constitute model self-assembling colloidal systems and biomaterials.
脂肽可以自组装成各种纳米结构，这些纳米结构可以通过编程整合肽序列，以实现一系列显著的生物活性。在此，我们研究了一系列带有两个赖氨酸或D-赖氨酸残基以及酪氨酸或色氨酸残基并连接到十六烷基脂链上的脂肽中，肽序列和手性对胶束结构及相互作用的影响。所有分子在临界胶束浓度（CMC）以上都会自组装成胶束。小角X射线散射（SAXS）用于从形状因子探测胶束形状和结构，并通过结构因子分析探测胶束间相互作用。通过表面张力和电导率测量一致地获得CMC。我们引入了一种从SAXS结构因子获得zeta电位的方法，该方法与直接测量值高度吻合。原子分子动力学模拟为构成模型自组装胶体系统和生物材料的脂肽胶束内的分子堆积和构象提供了见解。
