BACTENECINS AS CELL-PENETRATING PEPTIDES
Cell-Penetrating Peptides (CPPs) are molecules that can easily internalize into eukaryotic cells, as well as deliver across their membranes a variety of compounds (proteins, nucleic acids, liposomes, nanoparticles, etc.). CPPs are considered as promising components of anticancer drugs, serving for delivery of active ingredients into malignant cells, therefore, a detailed study of a mechanism of action of CPPs and search for novel, more effective peptides are vital tasks of current biological and medical research. An ability of proline-rich peptides bactenecins (ChBac5, ChBac3.4, mini-ChBac7.5Na) and their truncated variants to penetrate into eukaryotic cells has been explored. By means of flow cytometry and confocal microscopy, we found that these peptides, tagged with a fluorescent dye BODIPY FL, rapidly penetrated into tumor cells and, to a lesser extent, into normal mammalian cells in vitro. The dependence of the internalization process on the medium temperature and energy metabolism of target cells was studied. The obtained data on the cell-penetratin activity of caprine bactenecins confirm the prospect of further investigations of these peptides as prototypes of new compounds - carriers of drugs into malignant or infected cells.