Solution structure and membrane interaction mode of an antimicrobial peptide gaegurin 4.
We have applied NMR spectroscopy to determine the high-resolution structure of gaegurin 4, a 37-residue antimicrobial peptide from Rana rugosa, under varying hydrophobic conditions. Even in 100% H2O, gaegurin 4 contains a nascent turn near its C-terminal Rana box. Under a more hydrophobic condition it forms two amphipathic helices, one long encompassing residues 2-23 and the other consisting of residues 25-34, similar to what has been observed in cecropin A. Functional implication of the helix-breaking kink at Gly24 in gaegurin 4 was investigated by preparing several analogs. Based upon the current and previous results, we propose a novel seaanemone-like ion pore-forming model for gaegurin 4.
Chi
Seung-Wook
SW
Molecular Cancer Research Center, Division of Molecular Therapeutics, KRIBB, Daejeon 305-806, Republic of Korea.
Kim
Jae-Sung
JS
Kim
Do-Hyoung
DH
Lee
Si-Hyung
SH
Park
Yong-Ha
YH
Han
Kyou-Hoon
KH
D000595:Amino Acid Sequence; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry; D002462:Cell Membrane / Q000737:chemistry*; D003198:Computer Simulation; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D011498:Protein Precursors / Q000737:chemistry* / Q000648:ultrastructure*; D012996:Solutions
D023181:Antimicrobial Cationic Peptides; D011498:Protein Precursors; D012996:Solutions; C096396:gaegurin 4