LAUSR

In this study, we investigated the possible mode of action of two C-terminally amidated novel peptides identified from the frog skin on both Gram-positive (Staphylococcus aureus) and Gram-negative bacteria (Vibrio cholerae). The results indicate that the peptides initially induce membrane depolarization followed by pore formation in a concentration-dependent manner. A microscopic examination revealed the fact that the peptides are capable of destroying bacterial cells physically. The activity of these peptides against Gram-negative bacteria was dependent on the presence of divalent cations (Ca2+ and Mg2+) but not in Gram-positive bacteria. This study also emphasizes that the endemic frogs of the Western Ghats may provide a valuable source of its skin peptides having the potential for further improvement as lead drug molecules.