Antibiotic activity and structural analysis of the scorpion-derived antimicrobial peptide IsCT and its analogs |
| |
Authors: | Lee Kyungik Shin Song Yub Kim Kyoungho Lim Shin Saeng Hahm Kyung-Soo Kim Yangmee |
| |
Affiliation: | Department of Chemistry and Bio/Molecular Informatics Center, Konkuk University, Seoul 143-701, Republic of Korea. |
| |
Abstract: | IsCT is a non-cell-selective antimicrobial peptide isolated from the scorpion Opisthacanthus madagascariensis that has potent cytolytic activity against both mammalian and bacterial cells. To investigate the structure-activity relationships of IsCT and to design novel peptide antibiotics with bacterial cell selectivity, we synthesized several analogs of IsCT and determined their three-dimensional structures in solution by 2D-NMR spectroscopy. IsCT has a linear alpha-helical structure from Gly3 to Phe13, and [K7]-IsCT has a linear alpha-helical structure from Leu2 to Phe13. [K7, P8, K11]-IsCT, which has a bend in its middle region, exhibited the highest antibacterial activity without hemolytic activity, suggesting that its proline-induced bend is an important determinant of this selectivity. Tryptophan fluorescence showed that the high selectivity of [K7, P8, K11]-IsCT toward bacterial cells is closely correlated with its highly selective interaction with negatively charged phospholipids. Its potent activity against antibiotic-resistant bacteria suggests that [K7, P8, K11]-IsCT may serve as a promising lead candidate in the development of new peptide antibiotics. |
| |
Keywords: | Antimicrobial peptide IsCT NMR Bacterial cell selectivity Phospholipid selectivity |
本文献已被 ScienceDirect PubMed 等数据库收录! |
|