Conformation and dynamics of the chemotactic peptide formyl-L-methionyl-L-leucyl-L-phenylalanine in solution.

Several conformational and dynamic features of the chemotactic peptide formyl-L-methionyl-L-leucyl-L-phenylalanine in solution have been delineated by investigations of NMR and IR spectroscopic parameters. Both 1D and 2D NMR experiments have been performed for detection of scalar and dipolar proton-proton connectivities, whereas 13C and 1H relaxation parameters have been interpreted in terms of molecular dynamics. The main conformation appeared to be unfolded with the three hydrophobic side chains extending in divergent directions with respect to the backbone. The existence of relatively weak intermolecular hydrogen bonds was demonstrated, involving the formamide end group, with increase in the hydrophobicity of the external surface.