Non-ribosomally synthesized channels. These molecules, often chains of L- and D-amino acids as well as other small molecular building blocks such as hydroxy acids (i.e., lactate), form oligomeric transmembrane ion channels. Voltage may induce channel formation by promoting assembly of the oligomeric transmembrane pore-forming structure. These depsipeptides are often made by bacteria and fungi as agents of biological warfare. Other substances, completely lacking amino acids, are also capable of channel-formation. Man-made nanopores are also included in this subclass which may transport water (Lynch et al. 2020). Chemical and biological modifications of functionalised nanopores have been reviewed (Cairns-Gibson and Cockroft 2022). Advances in the de novo design of artificial transporters and channels have been reviewed (Zhou and Lu 2022). Synthetic peptide scaffolds as ion channels and molecular carriers have also been reviewed (Pérez-Pérez et al. 2025). Different kinds of synthetic ion channels including their design principles, dynamic regulations and therapeutic applications have been reviewed (Yan and Liu 2025) (Huang et al. 2024).