NMR Spectroscopic Assessment of the Structure and Dynamic Properties of an Amphibian Antimicrobial Peptide (Gaegurin 4) Bound to SDS Micelles

Sang-Ho Park, Woo-Sung Son, Yong-Jin Kim, Ae-Ran Kwon, Bong-Jin Lee
2007 BMB Reports  
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
more » ... c 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 o -120 o from each other.
doi:10.5483/bmbrep.2007.40.2.261 pmid:17394777 fatcat:fzdq4ekkbrgizhuqvo6vyqq2au