Discreetness of a cell is the key to life, with the cell membrane separating the interior cytosol from its environment. In this regard, cytosol is never connected to the external media even during the course of cell fission or fusion. However, water-soluble peptides called protein transduction domain (PTD) can spontaneously translocate through the cell membranes without any particular transporter or receptor. Here, we propose that the translocation of PTD can be described based on a local and temporal dynamic topological transformation of the membrane structure to mesh phase.