PGLa is a 21-residue cationic amphipathic peptide found in the skin glands of Xenopus laevis frogs. It contains four cationic lysine residues, one polar serine residue, and sixteen hydrophobic residues . PGLa exhibits hemolytic activity, with limited ability to differentiate between bacterial and mammalian membranes, as indicated by a therapeutic index (HC 50 /IC 50 ) of less than 1 (i.e., its potency on human cells is comparable to that on bacterial cells) . PGLa has been shown to form micelles and undergo significant conformational changes when interacting with a DMPC/DMPG membrane mixture . MD simulations by Bowers et al. using the same membrane model revealed that PGLa's helicity increases upon membrane binding, which is accompanied by lipid redistribution, causing DMPG lipids to cluster near the 2.1 Membrane-active AMPs peptide. This mechanism (illustrated in Figure A) was initially hypothesized to explain the activity of some surface-binding peptides .