Figure 3.

Biological activity of selected peptides. A) Sequences of all selected peptides, and the library from which they were selected. Our shorthand peptide notation uses an asterisk for the terminal basic cassette and identifies only the 4 varied O residues directly (see text). The 10 vesicle-selected sequences are described elsewhere (12, 13). Three sequences from each of the biological assays were determined and are shown. B) Minimum sterilizing concentration of all peptides against two gram-negative bacteria, E. coli and P. aeruginosa, a gram-positive bacteria, S. aureus, and a fungus, C. neoformans. Indolicidin is a natural bovine neutrophil AMP (22). Data for the 10 vesicle-selected peptides are given as an average (se<0.5) from our published data (12). Individual values are given in Supplemental Table 1. Minimum sterilizing concentrations of peptides were measured in ≥3 independent experiments for each peptide/organism. ses are ±0.5–2 μM. C) Membrane permeabilization assays on lipid vesicles, human cells, and bacteria, as described elsewhere (12, 16). All measurements were repeated ≥3 times and are expressed relative to permeabilization caused by detergent solubilization or lysis with 5 μM of the lytic venom peptide melittin. ses for permeabilization are 3–10%.