Table 1. Amino acid sequences and minimal inhibitory concentrations of CATH-2 analogs.
| Peptide | Amino acid sequence | Length /Charge | MIC (μM) |
|---|---|---|---|
| C(1–15) | RFGRFLRKIRRFRPK | 15, +8 | 16.7 ± 5.8 |
| CATH-2 | RFGRFLRKIRRFRPKVTITIQGSARF-NH2 | 26, +10 | 5.0 ± 0.0 |
| C(1–21) | RFGRFLRKIRRFRPKVTITIQ-NH2 | 21, +9 | 13.3 ± 5.8 |
| C(4–21) | RFLRKIRRFRPKVTITIQ-NH2 | 18, +8 | 6.7 ± 2.9 |
| C(5–21) | FLRKIRRFRPKVTITIQ-NH2 | 17, +7 | 8.3 ± 5.8 |
| C(7–21) | RKIRRFRPKVTITIQ-NH2 | 15, +7 | 8.3 ± 2.9 |
| C(8–21) | KIRRFRPKVTITIQ-NH2 | 14, +6 | 11.7 ± 7.6 |
| C(9–21) | IRRFRPKVTITIQ-NH2 | 13, +5 | 8.3 ± 2.9 |
| C(10–21) | RRFRPKVTITIQ-NH2 | 12, +5 | 6.7 ± 2.9 |
| C(11–21) | RFRPKVTITIQ-NH2 | 11, +4 | 8.3 ± 2.9 |
| C(1–21)W3 | RWGRWLRKIRRWRPKVTITIQ-NH2 | 21, +9 | 13.3 ± 5.8 |
| C(4–21)W2 | RWLRKIRRWRPKVTITIQ-NH2 | 18, +8 | 8.3 ± 2.9 |
| C(7–21)W | RKIRRWRPKVTITIQ-NH2 | 15, +7 | 13.3 ± 5.8 |
| C(10–21)W | RRWRPKVTITIQ-NH2 | 12, +5 | 11.7 ± 7.6 |
| C(1–21)Y3 | RYGRYLRKIRRYRPKVTITIQ-NH2 | 21, +9 | 10.0 ± 0.0 |
| C(4–21)Y2 | RYLRKIRRYRPKVTITIQ-NH2 | 18, +8 | 10.0 ± 0.0 |
| C(7–21)Y | RKIRRYRPKVTITIQ-NH2 | 15, +7 | 11.7 ± 7.6 |
| C(10–21)Y | RRYRPKVTITIQ-NH2 | 12, +5 | 16.7 ± 5.8 |
Length is measured in amino acids and substituted amino acid residues are underlined. Antibacterial activity of CATH-2 analogs against avian pathogenic E. coli in colony count assays. Means ± SEM for 3 independent experiments.