Chiral Semiconductor Nanoparticles for Site-Selective Photoinduced Cleavage of DNA Phosphodiester Bond

chiral cysteine (Cys)-modified cadmium telluride (CdTe) nanoparticles (NPs) are shown to specifically recognize double-stranded DNA exceeding 90 base pairs and to selectively cut upon photonic excitation at the restriction site GAT¢ATC (¢ indicates the cleavage site). Notably, our results demonstrate that cleavage activity originates from photoinduced reactive oxygen species. This site-specific cleavage is attributed to the affinity between the Cys-modified CdTe and the specific DNA conformation proved by quantum chemically calculated interaction energies. Remarkably, the photoactive chiral NPs developed here as sequence-specific endonucleases performed well in living cells and in <i>vivo</i>.

手性半胱氨酸（Cys）修饰碲化镉（CdTe）纳米颗粒（NPs）可特异性识别碱基对数目超过90的双链DNA，并在光子激发下于限制性酶切位点GAT¢ATC（¢代表切割位点）处实现选择性切割。值得注意的是，本研究结果表明，其切割活性源于光诱导活性氧物种。该位点特异性切割行为归因于Cys修饰的CdTe与特定DNA构象之间的亲和力，该结论通过量子化学计算得到的相互作用能得以验证。尤为突出的是，本文开发的这款作为序列特异性核酸内切酶的光活性手性纳米颗粒，在活细胞及<i>in vivo</i>活体环境中均表现出优异的性能。