title: NMR spectroscopic assessment of the structure and dynamic properties of an amphibian antimicrobial peptide (Gaegurin 4) bound to SDS micelles.
abstract: The structure and dynamics of a 37-residue antimicrobial peptide gaegurin 4 (GGN4) isolated from the skin of the native Korean frog, Rana rugosa, was determined in SDS micelles by NMR spectroscopy. The solution structure of the peptide in SDS micelles was determined from 352 NOE-derived distance constraints and 22 backbone torsion angle constraints. Dynamic properties for the amide backbone were characterized by (1)H-(15)N heteronuclear NOE experiments. The structural study revealed two amphipathic helices spanning residues 2-10 and 16-32 and that the helices were connected by a flexible loop. An intraresidue disulfide bridge was formed between residues Cys31 and Cys37 near the C-terminus. The loop region (11-15) connecting the two helices are were slightly more flexible than these helices themselves. From the fact that since there is no contact NOEs between two helices, it is implied that the GGN4 peptide shows an independent motion of both helices which has an angle of about 60 degrees -120 degrees from each other.
authors: Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, San 56-1, Shillim-dong, Gwanak-gu, Seoul 151-742, Republic of Korea.
authors: Sangho
authors: S
authors: Park
authors: Woo-Sung
authors: WS
authors: Son
authors: Yong-Jin
authors: YJ
authors: Kim
authors: Ae-Ran
authors: AR
authors: Kwon
authors: Bong-Jin
authors: BJ
authors: Lee
mesh_terms: D000595:Amino Acid Sequence; D000663:Amphibians / Q000378:metabolism*; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry* / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007473:Ion Channels / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D008823:Micelles; D008969:Molecular Sequence Data; D011485:Protein Binding; D017433:Protein Structure, Secondary; D012967:Sodium Dodecyl Sulfate / Q000378:metabolism*; D013696:Temperature
chemical_list: D023181:Antimicrobial Cationic Peptides; D007473:Ion Channels; D008823:Micelles; C468569:gaegurin protein, Rana rugosa; D012967:Sodium Dodecyl Sulfate