Conformational studies of N-Tyr-MIF-1 in aqueous solution by super(1)H nuclear magnetic resonance spectroscopy

N-Tyr-MIF-1 (Tyr-Pro-Leu-Gly-NH sub(2)) is an endogenous brain peptide with multiple effects on animal behavior. However, there have been no studies on the conformation of this tetrapeptide. We studied the conformation of N-Tyr-MIF-1 in aqueous solution by conventional one-dimensional and two-dimensional (COSY and NOESY) super(1)H nuclear magnetic resonance spectroscopy at 300 MHz. A complete set of assignments for the resolved resonances and approximate assignments for the overlapping resonances were made. The results demonstrate that N-Tyr-MIF-1 is in slow exchange between two conformers, most likely determined by the cis and trans states of the proline residue.