Bioinspired assemblies bear massive potential for energy generation and storage. Yet, biological molecules have severe limitations for charge transfer. Here, we report l-tryptophan-d-tryptophan assembling architectures comprising alternating water and peptide layers. The extensive connection of water molecules results in significant dipole-dipole interactions and piezoelectric response that can be further engineered by doping iodine adsorption or isotope replacement with no change in the chemical composition. This simple system and the new doping strategies supply alternative solutions for enhancing charge transfer in bioinspired supramolecular architectures.