Modular Redesign of a Cationic Lytic Peptide To Promote the Endosomal Escape of Biomacromolecules

Angew Chem Int Ed Engl. 2018 Sep 24;57(39):12771-12774. doi: 10.1002/anie.201807534. Epub 2018 Aug 30.


Endocytosis is an important route for the intracellular delivery of biomacromolecules, wherein their inefficient endosomal escape into the cytosol remains a major barrier. Based on the understanding that endosomal membranes are negatively charged, we focused on the potential of cationic lytic peptides for developing endosomolysis agents to release such entrapped molecules. As such, a venom peptide, Mastoparan X, was employed and redesigned to serve as a delivery tool. Appending a tri-glutamate unit to the N-terminus attenuates the cytotoxicity of Mastoparan X by about 40 fold, while introduction of a NiII -dipicolylamine complex enhances cellular uptake of the peptide by about 17 fold. Using the optimized peptide, various fluorescently labeled macromolecules were successfully delivered to the cytosol, enabling live-cell imaging of acetylated histones.

Keywords: cytotoxicity; drug delivery; membranes; peptides; tridentate ligands.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cations / chemistry
  • Cell Survival / drug effects
  • Coordination Complexes / chemistry
  • Cytosol / metabolism
  • Dextrans / chemistry
  • Dextrans / metabolism
  • Endocytosis
  • Endosomes / metabolism*
  • Fluorescent Dyes / chemistry
  • HeLa Cells
  • Humans
  • Intercellular Signaling Peptides and Proteins
  • Liposomes / metabolism
  • Microscopy, Confocal
  • Nickel / chemistry
  • Peptides / chemistry
  • Peptides / metabolism*
  • Peptides / pharmacology


  • Cations
  • Coordination Complexes
  • Dextrans
  • Fluorescent Dyes
  • Intercellular Signaling Peptides and Proteins
  • Liposomes
  • Peptides
  • mastoparan X
  • Nickel