Titile: Chiral Transformation of Cyanine Dye Aggregates Induced by Small Peptides

摘要

Three small peptides (K4, K5 and K6) with different length were designed to induce the transformation of the assembled state and the chirality of cyanine dye supramolecule. The absorption and circular dichroism (CD) results indicated that, the peptides intend to induce cyanine dye to H-aggregation, competed with Na+in PBS, which would induce dye to J-aggregation. Meanwhile, all three peptides could influence the chirality of both J-aggregates induced by Na+and Haggregates, among which K6 could induce chiral reversion of J-aggregates. Furthermore, molecular modelling (Insight II software) and energy calculation (UCSF Chimera software) results have shown that the peptides with different chain length have different conformations. This might be the reason for cyanine dye to form the different chiral assembly induced by these oligo-peptide templates.