Journal
BIOCHEMISTRY
Volume 45, Issue 44, Pages 13323-13330Publisher
AMER CHEMICAL SOC
DOI: 10.1021/bi061424u
Keywords
-
Categories
Funding
- NIAID NIH HHS [AI-37945] Funding Source: Medline
- NIGMS NIH HHS [GM-066976, R01 GM066976] Funding Source: Medline
Ask authors/readers for more resources
The conformation and membrane topology of the disulfide-stabilized antimicrobial peptide tachyplesin I (TP) in lipid bilayers are determined by solid-state NMR spectroscopy. The backbone (phi and psi) torsion angles of Val(6) are found to be -133 degrees and 142 degrees, respectively, and the Val(6) CO-Phe(8) H-N distance is 4.6 angstrom. These constrain the middle of the N-terminal strand to a relatively ideal antiparallel beta-sheet conformation. In contrast, the phi angle of Gly(10) is +/- 85 degrees, consistent with beta-turn conformation. Thus, TP adopts a beta-hairpin conformation with straight strands, similar to its structure in aqueous solution but different from a recently reported structure in DPC micelles where bending of the two beta-strands was observed. The Val(6) and Gly(10) CO groups are both 6.8 angstrom from the lipid P-31, while the Val(6) side chain is in H-1 spin diffusion contact with the lipid acyl chains. These results suggest that TP is immersed in the glycerol backbone region of the membrane and is oriented roughly parallel to the plane of the membrane. This depth of insertion and orientation differs from those of the analogous beta-sheet antimicrobial peptide protegrin-1 and suggest the importance of structural amphiphilicity in determining the location and orientation of membrane peptides in lipid bilayers.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available