Increasingly, it is possible to design peptide and protein assemblies de novo from first principles or computationally. This approach provides new routes to functional synthetic polypeptides, including designs to target and bind proteins of interest. Much of this work has been developed in vitro. Therefore, a challenge is to deliver de novo polypeptides efficiently to sites of action within cells. Here we describe the design, characterisation, intracellular delivery, and subcellular localisation of a de novo synthetic peptide system. This system comprises a dual-function basic peptide, programmed both for cell penetration and target binding, and a complementary acidic peptide that can be fused to proteins of interest and introduced into cells using synthetic DNA. The designs are characterised in vitro using biophysical methods and X-ray crystallography. The utility of the system for delivery into mammalian cells and subcellular targeting is demonstrated by marking organelles and actively engaging functional protein complexes.

越来越多地可以从第一原理或通过计算从头设计肽和蛋白质组装。这种方法为功能性合成多肽提供了新途径，包括设计靶向和结合感兴趣的蛋白质。这项工作的大部分是在体外开发的。因此，一个挑战是将从头多肽有效地递送至细胞内的作用位点。在这里，我们描述了从头合成肽系统的设计、表征、细胞内递送和亚细胞定位。该系统包含一个双功能碱性肽，用于细胞穿透和靶标结合，以及一个互补酸性肽，可以与感兴趣的蛋白质融合并使用合成 DNA 引入细胞。使用生物物理方法和 X 射线晶体学对设计进行体外表征。通过标记细胞器和积极参与功能性蛋白质复合物，证明了该系统用于输送到哺乳动物细胞和亚细胞靶向的效用。