Along with recent progress of nanotechnology, concern has risen about biological impacts of nanoparticles deriving from their interaction with cell membranes. Nanoparticles tend to adsorb proteins in vivo. Therefore, the physical properties of the conjugates to cell membranes must be investigated to elucidate and assess their properties. We examined whether one-dimensional protein-based nanoparticles induce liposome leakage in physiological saline. Carbon nanotube conjugates with adsorbed lysozyme interacted with the liposome through electrostatic interaction, leading to liposome leakage. Surprisingly, amyloid fibrils of lysozyme resembled the conjugate in terms of their effects on liposome leakage. Results described herein provide new insight into the interaction between nanoparticles and cell membranes in terms of their shape, mechanical properties, and noncovalent interactions.