Chemical shift assignment and structural plasticity of a HIV fusion peptide derivative in dodecylphosphocholine micelles.
A "HFPK3" peptide containing the 23 residues of the human immunodeficiency virus (HIV) fusion peptide (HFP) plus three non-native C-terminal lysines was studied in dodecylphosphocholine (DPC) micelles with 2D 1H NMR spectroscopy. The HFP is at the N-terminus of the gp41 fusion protein and plays an important role in fusing viral and target cell membranes which is a critical step in viral infection. Unlike HFP, HFPK3 is monomeric in detergent-free buffered aqueous solution which may be a useful property for functional and structural studies. H alpha chemical shifts indicated that DPC-associated HFPK3 was predominantly helical from I4 to L12. In addition to the highest-intensity crosspeaks used for the first chemical shift assignment (denoted I), there were additional crosspeaks whose intensities were approximately 10% of those used for assignment I. A second assignment (II) for residues G5 to L12 as well as a few other residues was derived from these lower-intensity crosspeaks. Relative to the I shifts, the II shifts were different by 0.01-0.23 ppm with the largest differences observed for HN. Comparison of the shifts of DPC-associated HFPK3 with those of detergent-associated HFP and HFP derivatives provided information about peptide structures and locations in micelles.
Gabrys
Charles M
CM
Department of Chemistry, Michigan State University, East Lansing, MI 48824-1320, USA.
Weliky
David P
DP
D006678:HIV / Q000378:metabolism*; D008239:Lysine / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008823:Micelles; D010455:Peptides / Q000737:chemistry*; D010767:Phosphorylcholine / Q000031:analogs & derivatives* / Q000737:chemistry; D014760:Viral Fusion Proteins / Q000737:chemistry / Q000378:metabolism
D008823:Micelles; D010455:Peptides; D014760:Viral Fusion Proteins; D010767:Phosphorylcholine; C028810:dodecylphosphocholine; D008239:Lysine